diff --git a/pyPhotoAlbum/alignment.py b/pyPhotoAlbum/alignment.py
index 9e1307d..1abc5a7 100644
--- a/pyPhotoAlbum/alignment.py
+++ b/pyPhotoAlbum/alignment.py
@@ -65,14 +65,10 @@ class ElementMaximizer:
 
             # Calculate distances between rectangles
             horizontal_gap = max(
-                other_x - (x + w),  # Other is to the right
-                x - (other_x + other_w)  # Other is to the left
+                other_x - (x + w), x - (other_x + other_w)  # Other is to the right  # Other is to the left
             )
 
-            vertical_gap = max(
-                other_y - (y + h),  # Other is below
-                y - (other_y + other_h)  # Other is above
-            )
+            vertical_gap = max(other_y - (y + h), y - (other_y + other_h))  # Other is below  # Other is above
 
             # If rectangles overlap or are too close in both dimensions
             if horizontal_gap < self.min_gap and vertical_gap < self.min_gap:
@@ -80,8 +76,14 @@ class ElementMaximizer:
 
         return False
 
-    def find_max_scale(self, elem_idx: int, current_scale: float, max_search_scale: float = 3.0,
-                      tolerance: float = 0.001, max_iterations: int = 20) -> float:
+    def find_max_scale(
+        self,
+        elem_idx: int,
+        current_scale: float,
+        max_search_scale: float = 3.0,
+        tolerance: float = 0.001,
+        max_iterations: int = 20,
+    ) -> float:
         """
         Use binary search to find the maximum scale factor for an element.
 
@@ -171,8 +173,10 @@ class ElementMaximizer:
             ow, oh = other.size
 
             # Check if rectangles overlap (with min_gap consideration)
-            if (abs((x + w/2) - (ox + ow/2)) < (w + ow)/2 + self.min_gap and
-                abs((y + h/2) - (oy + oh/2)) < (h + oh)/2 + self.min_gap):
+            if (
+                abs((x + w / 2) - (ox + ow / 2)) < (w + ow) / 2 + self.min_gap
+                and abs((y + h / 2) - (oy + oh / 2)) < (h + oh) / 2 + self.min_gap
+            ):
                 return True
 
         return False
@@ -233,7 +237,9 @@ class ElementMaximizer:
             self.center_element_horizontally(elem)
             self.center_element_vertically(elem)
 
-    def maximize(self, max_iterations: int = 100, growth_rate: float = 0.05) -> List[Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]]:
+    def maximize(
+        self, max_iterations: int = 100, growth_rate: float = 0.05
+    ) -> List[Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]]:
         """
         Execute the maximization algorithm.
 
@@ -365,7 +371,9 @@ class AlignmentManager:
         return changes
 
     @staticmethod
-    def align_horizontal_center(elements: List[BaseLayoutElement]) -> List[Tuple[BaseLayoutElement, Tuple[float, float]]]:
+    def align_horizontal_center(
+        elements: List[BaseLayoutElement],
+    ) -> List[Tuple[BaseLayoutElement, Tuple[float, float]]]:
         """
         Align all elements to horizontal center.
 
@@ -413,7 +421,9 @@ class AlignmentManager:
         return changes
 
     @staticmethod
-    def make_same_size(elements: List[BaseLayoutElement]) -> List[Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]]:
+    def make_same_size(
+        elements: List[BaseLayoutElement],
+    ) -> List[Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]]:
         """
         Make all elements the same size as the first element.
 
@@ -435,7 +445,9 @@ class AlignmentManager:
         return changes
 
     @staticmethod
-    def make_same_width(elements: List[BaseLayoutElement]) -> List[Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]]:
+    def make_same_width(
+        elements: List[BaseLayoutElement],
+    ) -> List[Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]]:
         """
         Make all elements the same width as the first element.
 
@@ -457,7 +469,9 @@ class AlignmentManager:
         return changes
 
     @staticmethod
-    def make_same_height(elements: List[BaseLayoutElement]) -> List[Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]]:
+    def make_same_height(
+        elements: List[BaseLayoutElement],
+    ) -> List[Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]]:
         """
         Make all elements the same height as the first element.
 
@@ -479,7 +493,9 @@ class AlignmentManager:
         return changes
 
     @staticmethod
-    def distribute_horizontally(elements: List[BaseLayoutElement]) -> List[Tuple[BaseLayoutElement, Tuple[float, float]]]:
+    def distribute_horizontally(
+        elements: List[BaseLayoutElement],
+    ) -> List[Tuple[BaseLayoutElement, Tuple[float, float]]]:
         """
         Distribute elements evenly across horizontal span.
 
@@ -613,7 +629,9 @@ class AlignmentManager:
         return changes
 
     @staticmethod
-    def fit_to_page_width(element: BaseLayoutElement, page_width: float) -> Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]:
+    def fit_to_page_width(
+        element: BaseLayoutElement, page_width: float
+    ) -> Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]:
         """
         Resize element to fit page width while maintaining aspect ratio.
 
@@ -638,7 +656,9 @@ class AlignmentManager:
         return (element, old_pos, old_size)
 
     @staticmethod
-    def fit_to_page_height(element: BaseLayoutElement, page_height: float) -> Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]:
+    def fit_to_page_height(
+        element: BaseLayoutElement, page_height: float
+    ) -> Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]:
         """
         Resize element to fit page height while maintaining aspect ratio.
 
@@ -663,7 +683,9 @@ class AlignmentManager:
         return (element, old_pos, old_size)
 
     @staticmethod
-    def fit_to_page(element: BaseLayoutElement, page_width: float, page_height: float) -> Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]:
+    def fit_to_page(
+        element: BaseLayoutElement, page_width: float, page_height: float
+    ) -> Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]:
         """
         Resize element to fit within page dimensions while maintaining aspect ratio.
 
@@ -702,7 +724,7 @@ class AlignmentManager:
         page_size: Tuple[float, float],
         min_gap: float = 2.0,
         max_iterations: int = 100,
-        growth_rate: float = 0.05
+        growth_rate: float = 0.05,
     ) -> List[Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]]:
         """
         Maximize element sizes using a crystal growth algorithm.
@@ -729,7 +751,7 @@ class AlignmentManager:
         element: BaseLayoutElement,
         page_size: Tuple[float, float],
         other_elements: List[BaseLayoutElement],
-        min_gap: float = 10.0
+        min_gap: float = 10.0,
     ) -> Tuple[BaseLayoutElement, Tuple[float, float], Tuple[float, float]]:
         """
         Expand a single element until it is min_gap away from page edges or other elements.
diff --git a/pyPhotoAlbum/asset_heal_dialog.py b/pyPhotoAlbum/asset_heal_dialog.py
index cdeb506..40f79de 100644
--- a/pyPhotoAlbum/asset_heal_dialog.py
+++ b/pyPhotoAlbum/asset_heal_dialog.py
@@ -6,9 +6,16 @@ import os
 import shutil
 from typing import List, Dict, Set
 from PyQt6.QtWidgets import (
-    QDialog, QVBoxLayout, QHBoxLayout, QLabel, QPushButton,
-    QListWidget, QListWidgetItem, QFileDialog, QGroupBox,
-    QMessageBox
+    QDialog,
+    QVBoxLayout,
+    QHBoxLayout,
+    QLabel,
+    QPushButton,
+    QListWidget,
+    QListWidgetItem,
+    QFileDialog,
+    QGroupBox,
+    QMessageBox,
 )
 from PyQt6.QtCore import Qt
 
@@ -124,10 +131,7 @@ class AssetHealDialog(QDialog):
     def _add_search_path(self):
         """Add a search path"""
         directory = QFileDialog.getExistingDirectory(
-            self,
-            "Select Search Path for Assets",
-            "",
-            QFileDialog.Option.ShowDirsOnly
+            self, "Select Search Path for Assets", "", QFileDialog.Option.ShowDirsOnly
         )
 
         if directory:
@@ -203,7 +207,7 @@ class AssetHealDialog(QDialog):
                 # Check if the found file needs to be imported
                 # (i.e., it's not already in the assets folder)
                 needs_import = True
-                if not os.path.isabs(asset_path) and asset_path.startswith('assets/'):
+                if not os.path.isabs(asset_path) and asset_path.startswith("assets/"):
                     # It's already a relative assets path, just missing from disk
                     # Copy it to the correct location
                     dest_path = os.path.join(self.project.folder_path, asset_path)
diff --git a/pyPhotoAlbum/asset_manager.py b/pyPhotoAlbum/asset_manager.py
index 77687bd..b3e1868 100644
--- a/pyPhotoAlbum/asset_manager.py
+++ b/pyPhotoAlbum/asset_manager.py
@@ -10,48 +10,48 @@ from pathlib import Path
 
 class AssetManager:
     """Manages project assets with automatic reference counting and cleanup"""
-    
+
     def __init__(self, project_folder: str):
         """
         Initialize AssetManager.
-        
+
         Args:
             project_folder: Root folder for the project
         """
         self.project_folder = project_folder
         self.assets_folder = os.path.join(project_folder, "assets")
         self.reference_counts: Dict[str, int] = {}  # {relative_path: count}
-        
+
         # Create assets folder if it doesn't exist
         os.makedirs(self.assets_folder, exist_ok=True)
-    
+
     def import_asset(self, source_path: str) -> str:
         """
         Import an asset into the project by copying it to the assets folder.
-        
+
         Args:
             source_path: Path to the source file
-            
+
         Returns:
             Relative path to the imported asset (e.g., "assets/photo_001.jpg")
         """
         if not os.path.exists(source_path):
             raise FileNotFoundError(f"Source file not found: {source_path}")
-        
+
         # Get filename and extension
         filename = os.path.basename(source_path)
         name, ext = os.path.splitext(filename)
-        
+
         # Find a unique filename if there's a collision
         counter = 1
         dest_filename = filename
         dest_path = os.path.join(self.assets_folder, dest_filename)
-        
+
         while os.path.exists(dest_path):
             dest_filename = f"{name}_{counter:03d}{ext}"
             dest_path = os.path.join(self.assets_folder, dest_filename)
             counter += 1
-        
+
         # Copy the file
         shutil.copy2(source_path, dest_path)
 
@@ -65,17 +65,17 @@ class AssetManager:
 
         # Return relative path for storage in elements
         return relative_path
-    
+
     def acquire_reference(self, asset_path: str):
         """
         Increment the reference count for an asset.
-        
+
         Args:
             asset_path: Relative path to the asset
         """
         if not asset_path:
             return
-        
+
         if asset_path in self.reference_counts:
             self.reference_counts[asset_path] += 1
             print(f"AssetManager: Acquired reference to {asset_path} (refs={self.reference_counts[asset_path]})")
@@ -87,25 +87,25 @@ class AssetManager:
                 print(f"AssetManager: Acquired reference to existing asset {asset_path} (refs=1)")
             else:
                 print(f"AssetManager: Warning - asset not found: {asset_path}")
-    
+
     def release_reference(self, asset_path: str):
         """
         Decrement the reference count for an asset.
         If count reaches zero, delete the asset file.
-        
+
         Args:
             asset_path: Relative path to the asset
         """
         if not asset_path:
             return
-        
+
         if asset_path not in self.reference_counts:
             print(f"AssetManager: Warning - attempting to release unknown asset: {asset_path}")
             return
-        
+
         self.reference_counts[asset_path] -= 1
         print(f"AssetManager: Released reference to {asset_path} (refs={self.reference_counts[asset_path]})")
-        
+
         if self.reference_counts[asset_path] <= 0:
             # No more references - safe to delete
             full_path = os.path.join(self.project_folder, asset_path)
@@ -116,37 +116,35 @@ class AssetManager:
                 del self.reference_counts[asset_path]
             except Exception as e:
                 print(f"AssetManager: Error deleting asset {asset_path}: {e}")
-    
+
     def get_absolute_path(self, relative_path: str) -> str:
         """
         Convert a relative asset path to an absolute path.
-        
+
         Args:
             relative_path: Relative path from project folder
-            
+
         Returns:
             Absolute path to the asset
         """
         return os.path.join(self.project_folder, relative_path)
-    
+
     def get_reference_count(self, asset_path: str) -> int:
         """
         Get the current reference count for an asset.
-        
+
         Args:
             asset_path: Relative path to the asset
-            
+
         Returns:
             Reference count (0 if not tracked)
         """
         return self.reference_counts.get(asset_path, 0)
-    
+
     def serialize(self) -> Dict:
         """Serialize asset manager state"""
-        return {
-            "reference_counts": self.reference_counts
-        }
-    
+        return {"reference_counts": self.reference_counts}
+
     def deserialize(self, data: Dict):
         """Deserialize asset manager state"""
         self.reference_counts = data.get("reference_counts", {})
diff --git a/pyPhotoAlbum/async_backend.py b/pyPhotoAlbum/async_backend.py
index 898e55f..ca0f46b 100644
--- a/pyPhotoAlbum/async_backend.py
+++ b/pyPhotoAlbum/async_backend.py
@@ -28,16 +28,14 @@ logger = logging.getLogger(__name__)
 
 class LoadPriority(Enum):
     """Priority levels for load requests."""
-    LOW = 0      # Offscreen, not visible
-    NORMAL = 1   # Potentially visible soon
-    HIGH = 2     # Visible on screen
-    URGENT = 3   # User is actively interacting with
+
+    LOW = 0  # Offscreen, not visible
+    NORMAL = 1  # Potentially visible soon
+    HIGH = 2  # Visible on screen
+    URGENT = 3  # User is actively interacting with
 
 
-def get_image_dimensions(
-    image_path: str,
-    max_size: Optional[int] = None
-) -> Optional[Tuple[int, int]]:
+def get_image_dimensions(image_path: str, max_size: Optional[int] = None) -> Optional[Tuple[int, int]]:
     """
     Extract image dimensions without loading the full image.
 
@@ -78,6 +76,7 @@ def get_image_dimensions(
 @dataclass(order=True)
 class LoadRequest:
     """Request to load and process an image."""
+
     priority: LoadPriority = field(compare=True)
     request_id: int = field(compare=True)  # Tie-breaker for same priority
     path: Path = field(compare=False)
@@ -111,7 +110,7 @@ class ImageCache:
         """Estimate memory size of PIL image in bytes."""
         # PIL images are typically width * height * bytes_per_pixel
         # RGBA = 4 bytes, RGB = 3 bytes, L = 1 byte
-        mode_sizes = {'RGBA': 4, 'RGB': 3, 'L': 1, 'LA': 2}
+        mode_sizes = {"RGBA": 4, "RGB": 3, "L": 1, "LA": 2}
         bytes_per_pixel = mode_sizes.get(img.mode, 4)
         return img.width * img.height * bytes_per_pixel
 
@@ -164,8 +163,7 @@ class ImageCache:
                 self.current_memory_bytes -= old_size
 
             # Evict LRU items if needed
-            while (self.current_memory_bytes + img_size > self.max_memory_bytes
-                   and len(self._cache) > 0):
+            while self.current_memory_bytes + img_size > self.max_memory_bytes and len(self._cache) > 0:
                 evicted_key, (evicted_img, evicted_size) = self._cache.popitem(last=False)
                 self.current_memory_bytes -= evicted_size
                 logger.debug(f"Cache EVICT: {evicted_key} ({evicted_size / 1024 / 1024:.1f}MB)")
@@ -174,10 +172,12 @@ class ImageCache:
             self._cache[key] = (img.copy(), img_size)
             self.current_memory_bytes += img_size
 
-            logger.debug(f"Cache PUT: {key} ({img_size / 1024 / 1024:.1f}MB) "
-                        f"[Total: {self.current_memory_bytes / 1024 / 1024:.1f}MB / "
-                        f"{self.max_memory_bytes / 1024 / 1024:.1f}MB, "
-                        f"Items: {len(self._cache)}]")
+            logger.debug(
+                f"Cache PUT: {key} ({img_size / 1024 / 1024:.1f}MB) "
+                f"[Total: {self.current_memory_bytes / 1024 / 1024:.1f}MB / "
+                f"{self.max_memory_bytes / 1024 / 1024:.1f}MB, "
+                f"Items: {len(self._cache)}]"
+            )
 
     def clear(self):
         """Clear entire cache."""
@@ -190,10 +190,10 @@ class ImageCache:
         """Get cache statistics."""
         with self._lock:
             return {
-                'items': len(self._cache),
-                'memory_mb': self.current_memory_bytes / 1024 / 1024,
-                'max_memory_mb': self.max_memory_bytes / 1024 / 1024,
-                'utilization': (self.current_memory_bytes / self.max_memory_bytes) * 100
+                "items": len(self._cache),
+                "memory_mb": self.current_memory_bytes / 1024 / 1024,
+                "max_memory_mb": self.max_memory_bytes / 1024 / 1024,
+                "utilization": (self.current_memory_bytes / self.max_memory_bytes) * 100,
             }
 
 
@@ -213,7 +213,7 @@ class AsyncImageLoader(QObject):
 
     # Signals for Qt integration
     image_loaded = pyqtSignal(object, object, object)  # (path, image, user_data)
-    load_failed = pyqtSignal(object, str, object)      # (path, error_msg, user_data)
+    load_failed = pyqtSignal(object, str, object)  # (path, error_msg, user_data)
 
     def __init__(self, cache: Optional[ImageCache] = None, max_workers: int = 4):
         """
@@ -227,8 +227,7 @@ class AsyncImageLoader(QObject):
 
         self.cache = cache or ImageCache()
         self.max_workers = max_workers
-        self.executor = ThreadPoolExecutor(max_workers=max_workers,
-                                           thread_name_prefix="ImageLoader")
+        self.executor = ThreadPoolExecutor(max_workers=max_workers, thread_name_prefix="ImageLoader")
 
         # Priority queue and tracking
         self._queue: asyncio.PriorityQueue = None  # Created when event loop starts
@@ -251,9 +250,9 @@ class AsyncImageLoader(QObject):
             return
 
         self._shutdown = False
-        self._loop_thread = threading.Thread(target=self._run_event_loop,
-                                             daemon=True,
-                                             name="AsyncImageLoader-EventLoop")
+        self._loop_thread = threading.Thread(
+            target=self._run_event_loop, daemon=True, name="AsyncImageLoader-EventLoop"
+        )
         self._loop_thread.start()
         logger.info("AsyncImageLoader event loop started")
 
@@ -354,12 +353,7 @@ class AsyncImageLoader(QObject):
 
             # Load in thread pool (I/O bound)
             loop = asyncio.get_event_loop()
-            img = await loop.run_in_executor(
-                self.executor,
-                self._load_and_process_image,
-                path,
-                target_size
-            )
+            img = await loop.run_in_executor(self.executor, self._load_and_process_image, path, target_size)
 
             # Cache result
             self.cache.put(path, img, target_size)
@@ -411,11 +405,13 @@ class AsyncImageLoader(QObject):
         """Emit load_failed signal (thread-safe)."""
         self.load_failed.emit(path, error_msg, user_data)
 
-    def request_load(self,
-                    path: Path,
-                    priority: LoadPriority = LoadPriority.NORMAL,
-                    target_size: Optional[Tuple[int, int]] = None,
-                    user_data: Any = None) -> bool:
+    def request_load(
+        self,
+        path: Path,
+        priority: LoadPriority = LoadPriority.NORMAL,
+        target_size: Optional[Tuple[int, int]] = None,
+        user_data: Any = None,
+    ) -> bool:
         """
         Request image load with specified priority.
 
@@ -446,7 +442,7 @@ class AsyncImageLoader(QObject):
                 request_id=self._next_request_id,
                 path=path,
                 target_size=target_size,
-                user_data=user_data
+                user_data=user_data,
             )
             self._next_request_id += 1
 
@@ -454,10 +450,7 @@ class AsyncImageLoader(QObject):
             self._pending_requests[path] = request
 
         # Submit to queue (thread-safe)
-        asyncio.run_coroutine_threadsafe(
-            self._queue.put(request),
-            self._loop
-        )
+        asyncio.run_coroutine_threadsafe(self._queue.put(request), self._loop)
 
         logger.debug(f"Queued load: {path} (priority: {priority.name})")
         return True
@@ -494,9 +487,9 @@ class AsyncImageLoader(QObject):
         """Get loader statistics."""
         with self._lock:
             return {
-                'pending': len(self._pending_requests),
-                'active': len(self._active_tasks),
-                'cache': self.cache.get_stats()
+                "pending": len(self._pending_requests),
+                "active": len(self._active_tasks),
+                "cache": self.cache.get_stats(),
             }
 
 
@@ -517,8 +510,8 @@ class AsyncPDFGenerator(QObject):
 
     # Signals for Qt integration
     progress_updated = pyqtSignal(int, int, str)  # (current, total, message)
-    export_complete = pyqtSignal(bool, list)      # (success, warnings)
-    export_failed = pyqtSignal(str)                # (error_message)
+    export_complete = pyqtSignal(bool, list)  # (success, warnings)
+    export_failed = pyqtSignal(str)  # (error_message)
 
     def __init__(self, image_cache: Optional[ImageCache] = None, max_workers: int = 2):
         """
@@ -532,8 +525,7 @@ class AsyncPDFGenerator(QObject):
 
         self.image_cache = image_cache or ImageCache()
         self.max_workers = max_workers
-        self.executor = ThreadPoolExecutor(max_workers=max_workers,
-                                           thread_name_prefix="PDFGenerator")
+        self.executor = ThreadPoolExecutor(max_workers=max_workers, thread_name_prefix="PDFGenerator")
 
         # Export state
         self._current_export: Optional[asyncio.Task] = None
@@ -554,9 +546,9 @@ class AsyncPDFGenerator(QObject):
             return
 
         self._shutdown = False
-        self._loop_thread = threading.Thread(target=self._run_event_loop,
-                                             daemon=True,
-                                             name="AsyncPDFGenerator-EventLoop")
+        self._loop_thread = threading.Thread(
+            target=self._run_event_loop, daemon=True, name="AsyncPDFGenerator-EventLoop"
+        )
         self._loop_thread.start()
         logger.info("AsyncPDFGenerator event loop started")
 
@@ -621,8 +613,7 @@ class AsyncPDFGenerator(QObject):
 
         # Submit export task
         self._current_export = asyncio.run_coroutine_threadsafe(
-            self._export_pdf_async(project, output_path, export_dpi),
-            self._loop
+            self._export_pdf_async(project, output_path, export_dpi), self._loop
         )
 
         logger.info(f"PDF export started: {output_path}")
@@ -662,11 +653,7 @@ class AsyncPDFGenerator(QObject):
             # Run export in thread pool
             loop = asyncio.get_event_loop()
             success, warnings = await loop.run_in_executor(
-                self.executor,
-                self._export_with_cache,
-                exporter,
-                output_path,
-                progress_callback
+                self.executor, self._export_with_cache, exporter, output_path, progress_callback
             )
 
             # Emit completion signal
@@ -731,13 +718,9 @@ class AsyncPDFGenerator(QObject):
     def is_exporting(self) -> bool:
         """Check if export is currently in progress."""
         with self._lock:
-            return (self._current_export is not None
-                   and not self._current_export.done())
+            return self._current_export is not None and not self._current_export.done()
 
     def get_stats(self) -> Dict[str, Any]:
         """Get generator statistics."""
         with self._lock:
-            return {
-                'exporting': self.is_exporting(),
-                'cache': self.image_cache.get_stats()
-            }
+            return {"exporting": self.is_exporting(), "cache": self.image_cache.get_stats()}
diff --git a/pyPhotoAlbum/async_project_loader.py b/pyPhotoAlbum/async_project_loader.py
index 8ee9d2f..c21342c 100644
--- a/pyPhotoAlbum/async_project_loader.py
+++ b/pyPhotoAlbum/async_project_loader.py
@@ -18,7 +18,7 @@ from pyPhotoAlbum.version_manager import (
     CURRENT_DATA_VERSION,
     check_version_compatibility,
     VersionCompatibility,
-    DataMigration
+    DataMigration,
 )
 
 
@@ -78,7 +78,7 @@ class AsyncProjectLoader(QThread):
             self.progress_updated.emit(10, 100, "Extracting project files...")
 
             # Extract ZIP contents with progress
-            with zipfile.ZipFile(self.zip_path, 'r') as zipf:
+            with zipfile.ZipFile(self.zip_path, "r") as zipf:
                 file_list = zipf.namelist()
                 total_files = len(file_list)
 
@@ -91,10 +91,7 @@ class AsyncProjectLoader(QThread):
                     # Update progress every 10 files or on last file
                     if i % 10 == 0 or i == total_files - 1:
                         progress = 10 + int((i / total_files) * 30)  # 10-40%
-                        self.progress_updated.emit(
-                            progress, 100,
-                            f"Extracting files... ({i + 1}/{total_files})"
-                        )
+                        self.progress_updated.emit(progress, 100, f"Extracting files... ({i + 1}/{total_files})")
 
             if self._cancelled:
                 return
@@ -103,12 +100,12 @@ class AsyncProjectLoader(QThread):
             self.progress_updated.emit(45, 100, "Loading project data...")
 
             # Load project.json
-            project_json_path = os.path.join(extract_to, 'project.json')
+            project_json_path = os.path.join(extract_to, "project.json")
             if not os.path.exists(project_json_path):
                 self.load_failed.emit("Invalid project file: project.json not found")
                 return
 
-            with open(project_json_path, 'r') as f:
+            with open(project_json_path, "r") as f:
                 project_data = json.load(f)
 
             if self._cancelled:
@@ -118,7 +115,7 @@ class AsyncProjectLoader(QThread):
             self.progress_updated.emit(55, 100, "Checking version compatibility...")
 
             # Check version compatibility
-            file_version = project_data.get('data_version', project_data.get('serialization_version', '1.0'))
+            file_version = project_data.get("data_version", project_data.get("serialization_version", "1.0"))
 
             is_compatible, error_msg = check_version_compatibility(file_version, self.zip_path)
             if not is_compatible:
@@ -141,7 +138,7 @@ class AsyncProjectLoader(QThread):
             self.progress_updated.emit(70, 100, "Creating project...")
 
             # Create new project
-            project_name = project_data.get('name', 'Untitled Project')
+            project_name = project_data.get("name", "Untitled Project")
             project = Project(name=project_name, folder_path=extract_to)
 
             # Deserialize project data
@@ -197,14 +194,14 @@ class AsyncProjectLoader(QThread):
                     original_path = element.image_path
 
                     # Skip if already a simple relative path
-                    if not os.path.isabs(original_path) and not original_path.startswith('./projects/'):
+                    if not os.path.isabs(original_path) and not original_path.startswith("./projects/"):
                         continue
 
                     # Pattern 1: "./projects/XXX/assets/filename.jpg" -> "assets/filename.jpg"
-                    if '/assets/' in original_path:
-                        parts = original_path.split('/assets/')
+                    if "/assets/" in original_path:
+                        parts = original_path.split("/assets/")
                         if len(parts) == 2:
-                            new_path = os.path.join('assets', parts[1])
+                            new_path = os.path.join("assets", parts[1])
                             element.image_path = new_path
                             normalized_count += 1
                             continue
@@ -222,9 +219,9 @@ class AsyncProjectLoader(QThread):
             print(f"Normalized {normalized_count} asset paths")
 
 
-def load_from_zip_async(zip_path: str, extract_to: Optional[str] = None,
-                         progress_callback=None, complete_callback=None,
-                         error_callback=None) -> AsyncProjectLoader:
+def load_from_zip_async(
+    zip_path: str, extract_to: Optional[str] = None, progress_callback=None, complete_callback=None, error_callback=None
+) -> AsyncProjectLoader:
     """
     Load a project from a ZIP file asynchronously.
 
diff --git a/pyPhotoAlbum/autosave_manager.py b/pyPhotoAlbum/autosave_manager.py
index b964914..827779b 100644
--- a/pyPhotoAlbum/autosave_manager.py
+++ b/pyPhotoAlbum/autosave_manager.py
@@ -86,11 +86,11 @@ class AutosaveManager:
             "project_name": project.name,
             "timestamp": datetime.now().isoformat(),
             "checkpoint_path": str(checkpoint_path),
-            "original_path": getattr(project, 'file_path', None),
+            "original_path": getattr(project, "file_path", None),
         }
 
-        metadata_path = checkpoint_path.with_suffix('.json')
-        with open(metadata_path, 'w') as f:
+        metadata_path = checkpoint_path.with_suffix(".json")
+        with open(metadata_path, "w") as f:
             json.dump(metadata, f, indent=2)
 
     def list_checkpoints(self, project_name: Optional[str] = None) -> List[Tuple[Path, dict]]:
@@ -106,23 +106,23 @@ class AutosaveManager:
         checkpoints = []
 
         for checkpoint_file in self.CHECKPOINT_DIR.glob(f"{self.CHECKPOINT_PREFIX}*{self.CHECKPOINT_EXTENSION}"):
-            metadata_file = checkpoint_file.with_suffix('.json')
+            metadata_file = checkpoint_file.with_suffix(".json")
 
             # Try to load metadata
             metadata = {}
             if metadata_file.exists():
                 try:
-                    with open(metadata_file, 'r') as f:
+                    with open(metadata_file, "r") as f:
                         metadata = json.load(f)
                 except:
                     pass
 
             # Filter by project name if specified
-            if project_name is None or metadata.get('project_name') == project_name:
+            if project_name is None or metadata.get("project_name") == project_name:
                 checkpoints.append((checkpoint_file, metadata))
 
         # Sort by timestamp (newest first)
-        checkpoints.sort(key=lambda x: x[1].get('timestamp', ''), reverse=True)
+        checkpoints.sort(key=lambda x: x[1].get("timestamp", ""), reverse=True)
         return checkpoints
 
     def load_checkpoint(self, checkpoint_path: Path):
@@ -157,7 +157,7 @@ class AutosaveManager:
                 checkpoint_path.unlink()
 
             # Delete metadata file
-            metadata_path = checkpoint_path.with_suffix('.json')
+            metadata_path = checkpoint_path.with_suffix(".json")
             if metadata_path.exists():
                 metadata_path.unlink()
 
@@ -190,7 +190,7 @@ class AutosaveManager:
 
         # Group checkpoints by project
         for checkpoint_path, metadata in self.list_checkpoints():
-            project_name = metadata.get('project_name', 'unknown')
+            project_name = metadata.get("project_name", "unknown")
             if project_name not in checkpoints_by_project:
                 checkpoints_by_project[project_name] = []
             checkpoints_by_project[project_name].append((checkpoint_path, metadata))
@@ -198,11 +198,11 @@ class AutosaveManager:
         # Clean up each project's checkpoints
         for project_name, checkpoints in checkpoints_by_project.items():
             # Sort by timestamp (newest first)
-            checkpoints.sort(key=lambda x: x[1].get('timestamp', ''), reverse=True)
+            checkpoints.sort(key=lambda x: x[1].get("timestamp", ""), reverse=True)
 
             for idx, (checkpoint_path, metadata) in enumerate(checkpoints):
                 # Delete if too old
-                timestamp_str = metadata.get('timestamp')
+                timestamp_str = metadata.get("timestamp")
                 if timestamp_str:
                     try:
                         timestamp = datetime.fromisoformat(timestamp_str)
diff --git a/pyPhotoAlbum/commands.py b/pyPhotoAlbum/commands.py
index e6c5b0f..9079e62 100644
--- a/pyPhotoAlbum/commands.py
+++ b/pyPhotoAlbum/commands.py
@@ -11,11 +11,11 @@ from pyPhotoAlbum.models import BaseLayoutElement, ImageData, PlaceholderData, T
 def _normalize_asset_path(image_path: str, asset_manager) -> str:
     """
     Convert absolute path to relative for asset manager.
-    
+
     Args:
         image_path: Image path (absolute or relative)
         asset_manager: AssetManager instance
-        
+
     Returns:
         Relative path suitable for asset manager
     """
@@ -29,79 +29,75 @@ def _normalize_asset_path(image_path: str, asset_manager) -> str:
 
 class Command(ABC):
     """Abstract base class for all commands"""
-    
+
     @abstractmethod
     def execute(self):
         """Execute the command"""
         pass
-    
+
     @abstractmethod
     def undo(self):
         """Undo the command"""
         pass
-    
+
     @abstractmethod
     def redo(self):
         """Redo the command (default implementation calls execute)"""
         self.execute()
-    
+
     @abstractmethod
     def serialize(self) -> Dict[str, Any]:
         """Serialize command to dictionary for saving"""
         pass
-    
+
     @staticmethod
     @abstractmethod
-    def deserialize(data: Dict[str, Any], project) -> 'Command':
+    def deserialize(data: Dict[str, Any], project) -> "Command":
         """Deserialize command from dictionary"""
         pass
 
 
 class AddElementCommand(Command):
     """Command for adding an element to a page"""
-    
+
     def __init__(self, page_layout, element: BaseLayoutElement, asset_manager=None):
         self.page_layout = page_layout
         self.element = element
         self.executed = False
         self.asset_manager = asset_manager
-        
+
         # Acquire reference to asset when command is created
         if self.asset_manager and isinstance(self.element, ImageData) and self.element.image_path:
             rel_path = _normalize_asset_path(self.element.image_path, self.asset_manager)
             self.asset_manager.acquire_reference(rel_path)
-    
+
     def execute(self):
         """Add the element to the page"""
         if not self.executed:
             self.page_layout.add_element(self.element)
             self.executed = True
-    
+
     def undo(self):
         """Remove the element from the page"""
         if self.executed:
             self.page_layout.remove_element(self.element)
             self.executed = False
-    
+
     def redo(self):
         """Re-add the element"""
         self.execute()
-    
+
     def serialize(self) -> Dict[str, Any]:
         """Serialize to dictionary"""
-        return {
-            "type": "add_element",
-            "element": self.element.serialize(),
-            "executed": self.executed
-        }
-    
+        return {"type": "add_element", "element": self.element.serialize(), "executed": self.executed}
+
     @staticmethod
-    def deserialize(data: Dict[str, Any], project) -> 'AddElementCommand':
+    def deserialize(data: Dict[str, Any], project) -> "AddElementCommand":
         """Deserialize from dictionary"""
         # Reconstruct element from serialized data
         elem_data = data["element"]
         elem_type = elem_data.get("type")
-        
+
         if elem_type == "image":
             element = ImageData()
         elif elem_type == "placeholder":
@@ -110,9 +106,9 @@ class AddElementCommand(Command):
             element = TextBoxData()
         else:
             raise ValueError(f"Unknown element type: {elem_type}")
-        
+
         element.deserialize(elem_data)
-        
+
         # Note: We need to find the correct page_layout
         # This will be handled by the CommandHistory deserializer
         cmd = AddElementCommand(None, element)
@@ -122,48 +118,44 @@ class AddElementCommand(Command):
 
 class DeleteElementCommand(Command):
     """Command for deleting an element from a page"""
-    
+
     def __init__(self, page_layout, element: BaseLayoutElement, asset_manager=None):
         self.page_layout = page_layout
         self.element = element
         self.executed = False
         self.asset_manager = asset_manager
-        
+
         # Acquire reference to asset to keep it alive while in undo history
         if self.asset_manager and isinstance(self.element, ImageData) and self.element.image_path:
             rel_path = _normalize_asset_path(self.element.image_path, self.asset_manager)
             self.asset_manager.acquire_reference(rel_path)
-    
+
     def execute(self):
         """Remove the element from the page"""
         if not self.executed:
             self.page_layout.remove_element(self.element)
             self.executed = True
-    
+
     def undo(self):
         """Re-add the element to the page"""
         if self.executed:
             self.page_layout.add_element(self.element)
             self.executed = False
-    
+
     def redo(self):
         """Re-remove the element"""
         self.execute()
-    
+
     def serialize(self) -> Dict[str, Any]:
         """Serialize to dictionary"""
-        return {
-            "type": "delete_element",
-            "element": self.element.serialize(),
-            "executed": self.executed
-        }
-    
+        return {"type": "delete_element", "element": self.element.serialize(), "executed": self.executed}
+
     @staticmethod
-    def deserialize(data: Dict[str, Any], project) -> 'DeleteElementCommand':
+    def deserialize(data: Dict[str, Any], project) -> "DeleteElementCommand":
         """Deserialize from dictionary"""
         elem_data = data["element"]
         elem_type = elem_data.get("type")
-        
+
         if elem_type == "image":
             element = ImageData()
         elif elem_type == "placeholder":
@@ -172,9 +164,9 @@ class DeleteElementCommand(Command):
             element = TextBoxData()
         else:
             raise ValueError(f"Unknown element type: {elem_type}")
-        
+
         element.deserialize(elem_data)
-        
+
         cmd = DeleteElementCommand(None, element)
         cmd.executed = data.get("executed", False)
         return cmd
@@ -182,39 +174,39 @@ class DeleteElementCommand(Command):
 
 class MoveElementCommand(Command):
     """Command for moving an element"""
-    
+
     def __init__(self, element: BaseLayoutElement, old_position: tuple, new_position: tuple):
         self.element = element
         self.old_position = old_position
         self.new_position = new_position
-    
+
     def execute(self):
         """Move element to new position"""
         self.element.position = self.new_position
-    
+
     def undo(self):
         """Move element back to old position"""
         self.element.position = self.old_position
-    
+
     def redo(self):
         """Move element to new position again"""
         self.execute()
-    
+
     def serialize(self) -> Dict[str, Any]:
         """Serialize to dictionary"""
         return {
             "type": "move_element",
             "element": self.element.serialize(),
             "old_position": self.old_position,
-            "new_position": self.new_position
+            "new_position": self.new_position,
         }
-    
+
     @staticmethod
-    def deserialize(data: Dict[str, Any], project) -> 'MoveElementCommand':
+    def deserialize(data: Dict[str, Any], project) -> "MoveElementCommand":
         """Deserialize from dictionary"""
         elem_data = data["element"]
         elem_type = elem_data.get("type")
-        
+
         if elem_type == "image":
             element = ImageData()
         elif elem_type == "placeholder":
@@ -223,41 +215,38 @@ class MoveElementCommand(Command):
             element = TextBoxData()
         else:
             raise ValueError(f"Unknown element type: {elem_type}")
-        
+
         element.deserialize(elem_data)
-        
-        return MoveElementCommand(
-            element,
-            tuple(data["old_position"]),
-            tuple(data["new_position"])
-        )
+
+        return MoveElementCommand(element, tuple(data["old_position"]), tuple(data["new_position"]))
 
 
 class ResizeElementCommand(Command):
     """Command for resizing an element"""
-    
-    def __init__(self, element: BaseLayoutElement, old_position: tuple, old_size: tuple, 
-                 new_position: tuple, new_size: tuple):
+
+    def __init__(
+        self, element: BaseLayoutElement, old_position: tuple, old_size: tuple, new_position: tuple, new_size: tuple
+    ):
         self.element = element
         self.old_position = old_position
         self.old_size = old_size
         self.new_position = new_position
         self.new_size = new_size
-    
+
     def execute(self):
         """Resize element to new size"""
         self.element.position = self.new_position
         self.element.size = self.new_size
-    
+
     def undo(self):
         """Resize element back to old size"""
         self.element.position = self.old_position
         self.element.size = self.old_size
-    
+
     def redo(self):
         """Resize element to new size again"""
         self.execute()
-    
+
     def serialize(self) -> Dict[str, Any]:
         """Serialize to dictionary"""
         return {
@@ -266,15 +255,15 @@ class ResizeElementCommand(Command):
             "old_position": self.old_position,
             "old_size": self.old_size,
             "new_position": self.new_position,
-            "new_size": self.new_size
+            "new_size": self.new_size,
         }
-    
+
     @staticmethod
-    def deserialize(data: Dict[str, Any], project) -> 'ResizeElementCommand':
+    def deserialize(data: Dict[str, Any], project) -> "ResizeElementCommand":
         """Deserialize from dictionary"""
         elem_data = data["element"]
         elem_type = elem_data.get("type")
-        
+
         if elem_type == "image":
             element = ImageData()
         elif elem_type == "placeholder":
@@ -283,15 +272,15 @@ class ResizeElementCommand(Command):
             element = TextBoxData()
         else:
             raise ValueError(f"Unknown element type: {elem_type}")
-        
+
         element.deserialize(elem_data)
-        
+
         return ResizeElementCommand(
             element,
             tuple(data["old_position"]),
             tuple(data["old_size"]),
             tuple(data["new_position"]),
-            tuple(data["new_size"])
+            tuple(data["new_size"]),
         )
 
 
@@ -308,7 +297,7 @@ class RotateElementCommand(Command):
         self.old_size = element.size
 
         # For ImageData, store the old PIL rotation state
-        if hasattr(element, 'pil_rotation_90'):
+        if hasattr(element, "pil_rotation_90"):
             self.old_pil_rotation = element.pil_rotation_90
         else:
             self.old_pil_rotation = None
@@ -344,9 +333,9 @@ class RotateElementCommand(Command):
                 self.element.position = (center_x - h / 2, center_y - w / 2)
 
             # Clear the texture so it will be reloaded with the new rotation
-            if hasattr(self.element, '_texture_id'):
+            if hasattr(self.element, "_texture_id"):
                 del self.element._texture_id
-            if hasattr(self.element, '_async_load_requested'):
+            if hasattr(self.element, "_async_load_requested"):
                 self.element._async_load_requested = False
 
             # Keep visual rotation at 0
@@ -376,29 +365,29 @@ class RotateElementCommand(Command):
         # For ImageData, restore PIL rotation and clear texture
         if isinstance(self.element, ImageData) and self.old_pil_rotation is not None:
             self.element.pil_rotation_90 = self.old_pil_rotation
-            if hasattr(self.element, '_texture_id'):
+            if hasattr(self.element, "_texture_id"):
                 self.element._texture_id = None
                 self.element._async_load_requested = False
 
     def redo(self):
         """Rotate element to new angle again"""
         self.execute()
-    
+
     def serialize(self) -> Dict[str, Any]:
         """Serialize to dictionary"""
         return {
             "type": "rotate_element",
             "element": self.element.serialize(),
             "old_rotation": self.old_rotation,
-            "new_rotation": self.new_rotation
+            "new_rotation": self.new_rotation,
         }
-    
+
     @staticmethod
-    def deserialize(data: Dict[str, Any], project) -> 'RotateElementCommand':
+    def deserialize(data: Dict[str, Any], project) -> "RotateElementCommand":
         """Deserialize from dictionary"""
         elem_data = data["element"]
         elem_type = elem_data.get("type")
-        
+
         if elem_type == "image":
             element = ImageData()
         elif elem_type == "placeholder":
@@ -407,78 +396,70 @@ class RotateElementCommand(Command):
             element = TextBoxData()
         else:
             raise ValueError(f"Unknown element type: {elem_type}")
-        
+
         element.deserialize(elem_data)
-        
-        return RotateElementCommand(
-            element,
-            data["old_rotation"],
-            data["new_rotation"]
-        )
+
+        return RotateElementCommand(element, data["old_rotation"], data["new_rotation"])
 
 
 class AdjustImageCropCommand(Command):
     """Command for adjusting image crop/pan within frame"""
-    
+
     def __init__(self, element: ImageData, old_crop_info: tuple, new_crop_info: tuple):
         self.element = element
         self.old_crop_info = old_crop_info
         self.new_crop_info = new_crop_info
-    
+
     def execute(self):
         """Apply new crop info"""
         self.element.crop_info = self.new_crop_info
-    
+
     def undo(self):
         """Restore old crop info"""
         self.element.crop_info = self.old_crop_info
-    
+
     def redo(self):
         """Apply new crop info again"""
         self.execute()
-    
+
     def serialize(self) -> Dict[str, Any]:
         """Serialize to dictionary"""
         return {
             "type": "adjust_image_crop",
             "element": self.element.serialize(),
             "old_crop_info": self.old_crop_info,
-            "new_crop_info": self.new_crop_info
+            "new_crop_info": self.new_crop_info,
         }
-    
+
     @staticmethod
-    def deserialize(data: Dict[str, Any], project) -> 'AdjustImageCropCommand':
+    def deserialize(data: Dict[str, Any], project) -> "AdjustImageCropCommand":
         """Deserialize from dictionary"""
         elem_data = data["element"]
         element = ImageData()
         element.deserialize(elem_data)
-        
-        return AdjustImageCropCommand(
-            element,
-            tuple(data["old_crop_info"]),
-            tuple(data["new_crop_info"])
-        )
+
+        return AdjustImageCropCommand(element, tuple(data["old_crop_info"]), tuple(data["new_crop_info"]))
 
 
 class AlignElementsCommand(Command):
     """Command for aligning multiple elements"""
-    
+
     def __init__(self, changes: List[tuple]):
         """
         Args:
             changes: List of (element, old_position) tuples
         """
         self.changes = changes
-    
+
     def execute(self):
         """Positions have already been set by AlignmentManager"""
         pass
-    
+
     def undo(self):
         """Restore old positions"""
         for element, old_position in self.changes:
             element.position = old_position
-    
+
     def redo(self):
         """Re-apply alignment (positions are stored in current state)"""
         # Store current positions and restore them
@@ -488,28 +469,22 @@ class AlignElementsCommand(Command):
         # Then re-apply new positions
         for element, new_position in new_positions:
             element.position = new_position
-    
+
     def serialize(self) -> Dict[str, Any]:
         """Serialize to dictionary"""
         return {
             "type": "align_elements",
-            "changes": [
-                {
-                    "element": elem.serialize(),
-                    "old_position": old_pos
-                }
-                for elem, old_pos in self.changes
-            ]
+            "changes": [{"element": elem.serialize(), "old_position": old_pos} for elem, old_pos in self.changes],
         }
-    
+
     @staticmethod
-    def deserialize(data: Dict[str, Any], project) -> 'AlignElementsCommand':
+    def deserialize(data: Dict[str, Any], project) -> "AlignElementsCommand":
         """Deserialize from dictionary"""
         changes = []
         for change_data in data.get("changes", []):
             elem_data = change_data["element"]
             elem_type = elem_data.get("type")
-            
+
             if elem_type == "image":
                 element = ImageData()
             elif elem_type == "placeholder":
@@ -518,17 +493,17 @@ class AlignElementsCommand(Command):
                 element = TextBoxData()
             else:
                 continue
-            
+
             element.deserialize(elem_data)
             old_position = tuple(change_data["old_position"])
             changes.append((element, old_position))
-        
+
         return AlignElementsCommand(changes)
 
 
 class ResizeElementsCommand(Command):
     """Command for resizing multiple elements"""
-    
+
     def __init__(self, changes: List[tuple]):
         """
         Args:
@@ -536,45 +511,41 @@ class ResizeElementsCommand(Command):
         """
         self.changes = changes
         self.new_states = [(elem, elem.position, elem.size) for elem, _, _ in changes]
-    
+
     def execute(self):
         """Sizes have already been set by AlignmentManager"""
         pass
-    
+
     def undo(self):
         """Restore old positions and sizes"""
         for element, old_position, old_size in self.changes:
             element.position = old_position
             element.size = old_size
-    
+
     def redo(self):
         """Re-apply new sizes"""
         for element, new_position, new_size in self.new_states:
             element.position = new_position
             element.size = new_size
-    
+
     def serialize(self) -> Dict[str, Any]:
         """Serialize to dictionary"""
         return {
             "type": "resize_elements",
             "changes": [
-                {
-                    "element": elem.serialize(),
-                    "old_position": old_pos,
-                    "old_size": old_size
-                }
+                {"element": elem.serialize(), "old_position": old_pos, "old_size": old_size}
                 for elem, old_pos, old_size in self.changes
-            ]
+            ],
         }
-    
+
     @staticmethod
-    def deserialize(data: Dict[str, Any], project) -> 'ResizeElementsCommand':
+    def deserialize(data: Dict[str, Any], project) -> "ResizeElementsCommand":
         """Deserialize from dictionary"""
         changes = []
         for change_data in data.get("changes", []):
             elem_data = change_data["element"]
             elem_type = elem_data.get("type")
-            
+
             if elem_type == "image":
                 element = ImageData()
             elif elem_type == "placeholder":
@@ -583,57 +554,57 @@ class ResizeElementsCommand(Command):
                 element = TextBoxData()
             else:
                 continue
-            
+
             element.deserialize(elem_data)
             old_position = tuple(change_data["old_position"])
             old_size = tuple(change_data["old_size"])
             changes.append((element, old_position, old_size))
-        
+
         return ResizeElementsCommand(changes)
 
 
 class ChangeZOrderCommand(Command):
     """Command for changing element z-order (list position)"""
-    
+
     def __init__(self, page_layout, element: BaseLayoutElement, old_index: int, new_index: int):
         self.page_layout = page_layout
         self.element = element
         self.old_index = old_index
         self.new_index = new_index
-    
+
     def execute(self):
         """Move element to new position in list"""
         elements = self.page_layout.elements
         if self.element in elements:
             elements.remove(self.element)
             elements.insert(self.new_index, self.element)
-    
+
     def undo(self):
         """Move element back to old position in list"""
         elements = self.page_layout.elements
         if self.element in elements:
             elements.remove(self.element)
             elements.insert(self.old_index, self.element)
-    
+
     def redo(self):
         """Move element to new position again"""
         self.execute()
-    
+
     def serialize(self) -> Dict[str, Any]:
         """Serialize to dictionary"""
         return {
             "type": "change_zorder",
             "element": self.element.serialize(),
             "old_index": self.old_index,
-            "new_index": self.new_index
+            "new_index": self.new_index,
         }
-    
+
     @staticmethod
-    def deserialize(data: Dict[str, Any], project) -> 'ChangeZOrderCommand':
+    def deserialize(data: Dict[str, Any], project) -> "ChangeZOrderCommand":
         """Deserialize from dictionary"""
         elem_data = data["element"]
         elem_type = elem_data.get("type")
-        
+
         if elem_type == "image":
             element = ImageData()
         elif elem_type == "placeholder":
@@ -642,25 +613,22 @@ class ChangeZOrderCommand(Command):
             element = TextBoxData()
         else:
             raise ValueError(f"Unknown element type: {elem_type}")
-        
+
         element.deserialize(elem_data)
-        
+
         return ChangeZOrderCommand(
-            None,  # page_layout will be set by CommandHistory
-            element,
-            data["old_index"],
-            data["new_index"]
+            None, element, data["old_index"], data["new_index"]  # page_layout will be set by CommandHistory
         )
 
 
 class StateChangeCommand(Command):
     """
     Generic command for operations that change state.
-    
+
     This command captures before/after snapshots of state and can restore them.
     Used by the @undoable_operation decorator.
     """
-    
+
     def __init__(self, description: str, restore_func, before_state: Any, after_state: Any = None):
         """
         Args:
@@ -673,31 +641,28 @@ class StateChangeCommand(Command):
         self.restore_func = restore_func
         self.before_state = before_state
         self.after_state = after_state
-    
+
     def execute(self):
         """State is already applied, just store after_state if not set"""
         # After state is captured by decorator after operation runs
         pass
-    
+
     def undo(self):
         """Restore to before state"""
         self.restore_func(self.before_state)
-    
+
     def redo(self):
         """Restore to after state"""
         self.restore_func(self.after_state)
-    
+
     def serialize(self) -> Dict[str, Any]:
         """Serialize to dictionary"""
         # For now, state change commands are not serialized
         # This could be enhanced later if needed
-        return {
-            "type": "state_change",
-            "description": self.description
-        }
-    
+        return {"type": "state_change", "description": self.description}
+
     @staticmethod
-    def deserialize(data: Dict[str, Any], project) -> 'StateChangeCommand':
+    def deserialize(data: Dict[str, Any], project) -> "StateChangeCommand":
         """Deserialize from dictionary"""
         # Not implemented - would need to serialize state
         raise NotImplementedError("StateChangeCommand deserialization not yet supported")
@@ -732,12 +697,12 @@ class CommandHistory:
         if len(self.undo_stack) > self.max_history:
             old_cmd = self.undo_stack.pop(0)
             self._release_command_assets(old_cmd)
-    
+
     def _release_command_assets(self, command: Command):
         """Release asset references held by a command"""
         if not self.asset_manager:
             return
-        
+
         # Release asset references for commands that hold them
         if isinstance(command, (AddElementCommand, DeleteElementCommand)):
             if isinstance(command.element, ImageData) and command.element.image_path:
@@ -746,7 +711,7 @@ class CommandHistory:
                 if os.path.isabs(asset_path):
                     asset_path = os.path.relpath(asset_path, self.asset_manager.project_folder)
                 self.asset_manager.release_reference(asset_path)
-    
+
     def undo(self) -> bool:
         """Undo the last command"""
         if not self.can_undo():
@@ -776,15 +741,15 @@ class CommandHistory:
             self.project.mark_dirty()
 
         return True
-    
+
     def can_undo(self) -> bool:
         """Check if undo is available"""
         return len(self.undo_stack) > 0
-    
+
     def can_redo(self) -> bool:
         """Check if redo is available"""
         return len(self.redo_stack) > 0
-    
+
     def clear(self):
         """Clear all history and release asset references"""
         # Release all asset references
@@ -792,36 +757,36 @@ class CommandHistory:
             self._release_command_assets(cmd)
         for cmd in self.redo_stack:
             self._release_command_assets(cmd)
-        
+
         self.undo_stack.clear()
         self.redo_stack.clear()
-    
+
     def serialize(self) -> Dict[str, Any]:
         """Serialize history to dictionary"""
         return {
             "undo_stack": [cmd.serialize() for cmd in self.undo_stack],
             "redo_stack": [cmd.serialize() for cmd in self.redo_stack],
-            "max_history": self.max_history
+            "max_history": self.max_history,
         }
-    
+
     def deserialize(self, data: Dict[str, Any], project):
         """Deserialize history from dictionary"""
         self.max_history = data.get("max_history", 100)
-        
+
         # Deserialize undo stack
         self.undo_stack = []
         for cmd_data in data.get("undo_stack", []):
             cmd = self._deserialize_command(cmd_data, project)
             if cmd:
                 self.undo_stack.append(cmd)
-        
+
         # Deserialize redo stack
         self.redo_stack = []
         for cmd_data in data.get("redo_stack", []):
             cmd = self._deserialize_command(cmd_data, project)
             if cmd:
                 self.redo_stack.append(cmd)
-    
+
     # Command type registry for deserialization
     _COMMAND_DESERIALIZERS = {
         "add_element": AddElementCommand.deserialize,
diff --git a/pyPhotoAlbum/decorators.py b/pyPhotoAlbum/decorators.py
index 884c3b8..e378c74 100644
--- a/pyPhotoAlbum/decorators.py
+++ b/pyPhotoAlbum/decorators.py
@@ -10,10 +10,10 @@ from typing import Optional, Callable
 class RibbonAction:
     """
     Decorator to mark methods as ribbon actions.
-    
+
     This decorator stores metadata about UI actions that should appear in the ribbon.
     The metadata is used to auto-generate the ribbon configuration.
-    
+
     Example:
         @RibbonAction(
             label="New",
@@ -26,7 +26,7 @@ class RibbonAction:
         def new_project(self):
             ...
     """
-    
+
     def __init__(
         self,
         label: str,
@@ -37,11 +37,11 @@ class RibbonAction:
         shortcut: Optional[str] = None,
         requires_page: bool = False,
         requires_selection: bool = False,
-        min_selection: int = 0
+        min_selection: int = 0,
     ):
         """
         Initialize the ribbon action decorator.
-        
+
         Args:
             label: Button label text
             tooltip: Tooltip text shown on hover
@@ -62,35 +62,36 @@ class RibbonAction:
         self.requires_page = requires_page
         self.requires_selection = requires_selection
         self.min_selection = min_selection
-    
+
     def __call__(self, func: Callable) -> Callable:
         """
         Decorate the function with ribbon action metadata.
-        
+
         Args:
             func: The function to decorate
-            
+
         Returns:
             The decorated function with metadata attached
         """
+
         @wraps(func)
         def wrapper(*args, **kwargs):
             return func(*args, **kwargs)
-        
+
         # Store metadata on wrapper function
         wrapper._ribbon_action = {
-            'label': self.label,
-            'tooltip': self.tooltip,
-            'tab': self.tab,
-            'group': self.group,
-            'icon': self.icon,
-            'shortcut': self.shortcut,
-            'action': func.__name__,
-            'requires_page': self.requires_page,
-            'requires_selection': self.requires_selection,
-            'min_selection': self.min_selection
+            "label": self.label,
+            "tooltip": self.tooltip,
+            "tab": self.tab,
+            "group": self.group,
+            "icon": self.icon,
+            "shortcut": self.shortcut,
+            "action": func.__name__,
+            "requires_page": self.requires_page,
+            "requires_selection": self.requires_selection,
+            "min_selection": self.min_selection,
         }
-        
+
         return wrapper
 
 
@@ -103,13 +104,13 @@ def ribbon_action(
     shortcut: Optional[str] = None,
     requires_page: bool = False,
     requires_selection: bool = False,
-    min_selection: int = 0
+    min_selection: int = 0,
 ) -> Callable:
     """
     Convenience function for the RibbonAction decorator.
-    
+
     This provides a lowercase function-style interface to the decorator.
-    
+
     Args:
         label: Button label text
         tooltip: Tooltip text shown on hover
@@ -120,7 +121,7 @@ def ribbon_action(
         requires_page: Whether this action requires an active page
         requires_selection: Whether this action requires selected elements
         min_selection: Minimum number of selected elements required
-        
+
     Returns:
         RibbonAction decorator instance
     """
@@ -133,17 +134,17 @@ def ribbon_action(
         shortcut=shortcut,
         requires_page=requires_page,
         requires_selection=requires_selection,
-        min_selection=min_selection
+        min_selection=min_selection,
     )
 
 
 class NumericalInput:
     """
     Decorator to mark methods that require numerical width/height inputs.
-    
+
     This decorator stores metadata about numerical input fields that should
     be presented in dialogs for methods that work with page dimensions.
-    
+
     Example:
         @numerical_input(
             fields=[
@@ -154,49 +155,48 @@ class NumericalInput:
         def set_page_size(self, width, height):
             ...
     """
-    
+
     def __init__(self, fields: list):
         """
         Initialize the numerical input decorator.
-        
+
         Args:
             fields: List of tuples, each containing:
                     (param_name, label, unit, min_value, max_value)
         """
         self.fields = fields
-    
+
     def __call__(self, func: Callable) -> Callable:
         """
         Decorate the function with numerical input metadata.
-        
+
         Args:
             func: The function to decorate
-            
+
         Returns:
             The decorated function with metadata attached
         """
+
         @wraps(func)
         def wrapper(*args, **kwargs):
             return func(*args, **kwargs)
-        
+
         # Store metadata on wrapper function
-        wrapper._numerical_input = {
-            'fields': self.fields
-        }
-        
+        wrapper._numerical_input = {"fields": self.fields}
+
         return wrapper
 
 
 def numerical_input(fields: list) -> Callable:
     """
     Convenience function for the NumericalInput decorator.
-    
+
     This provides a lowercase function-style interface to the decorator.
-    
+
     Args:
         fields: List of tuples, each containing:
                 (param_name, label, unit, min_value, max_value)
-        
+
     Returns:
         NumericalInput decorator instance
     """
@@ -206,10 +206,10 @@ def numerical_input(fields: list) -> Callable:
 class UndoableOperation:
     """
     Decorator to automatically create undo/redo commands for operations.
-    
+
     This decorator captures state before and after an operation, then creates
     a StateChangeCommand for undo/redo functionality.
-    
+
     Example:
         @undoable_operation(capture='page_elements')
         def apply_template(self):
@@ -217,11 +217,11 @@ class UndoableOperation:
             self.template_manager.apply_template(...)
             # Decorator handles undo/redo automatically
     """
-    
-    def __init__(self, capture: str = 'page_elements', description: str = None):
+
+    def __init__(self, capture: str = "page_elements", description: str = None):
         """
         Initialize the undoable operation decorator.
-        
+
         Args:
             capture: What to capture for undo/redo:
                 - 'page_elements': Capture elements of current page
@@ -230,89 +230,92 @@ class UndoableOperation:
         """
         self.capture = capture
         self.description = description
-    
+
     def __call__(self, func: Callable) -> Callable:
         """
         Decorate the function with automatic undo/redo.
-        
+
         Args:
             func: The function to decorate
-            
+
         Returns:
             The decorated function
         """
+
         @wraps(func)
         def wrapper(self_instance, *args, **kwargs):
             # Get description
-            description = self.description or func.__name__.replace('_', ' ').title()
-            
+            description = self.description or func.__name__.replace("_", " ").title()
+
             # Capture before state
             before_state = self._capture_state(self_instance, self.capture)
-            
+
             # Execute the operation
             result = func(self_instance, *args, **kwargs)
-            
-            # Capture after state  
+
+            # Capture after state
             after_state = self._capture_state(self_instance, self.capture)
-            
+
             # Create restore function
             def restore_state(state):
                 self._restore_state(self_instance, self.capture, state)
                 # Update view after restoring
-                if hasattr(self_instance, 'update_view'):
+                if hasattr(self_instance, "update_view"):
                     self_instance.update_view()
-            
+
             # Create and execute command
             from pyPhotoAlbum.commands import StateChangeCommand
+
             cmd = StateChangeCommand(description, restore_state, before_state, after_state)
-            
-            if hasattr(self_instance, 'project') and hasattr(self_instance.project, 'history'):
+
+            if hasattr(self_instance, "project") and hasattr(self_instance.project, "history"):
                 self_instance.project.history.execute(cmd)
                 print(f"Undoable operation '{description}' executed")
-            
+
             return result
-        
+
         return wrapper
-    
+
     def _capture_state(self, instance, capture_type: str):
         """Capture current state based on capture type"""
-        if capture_type == 'page_elements':
+        if capture_type == "page_elements":
             # Capture elements from current page
-            current_page = instance.get_current_page() if hasattr(instance, 'get_current_page') else None
+            current_page = instance.get_current_page() if hasattr(instance, "get_current_page") else None
             if current_page:
                 # Deep copy elements
                 return [copy.deepcopy(elem.serialize()) for elem in current_page.layout.elements]
             return []
-        
+
         return None
-    
+
     def _restore_state(self, instance, capture_type: str, state):
         """Restore state based on capture type"""
-        if capture_type == 'page_elements':
+        if capture_type == "page_elements":
             # Restore elements to current page
-            current_page = instance.get_current_page() if hasattr(instance, 'get_current_page') else None
+            current_page = instance.get_current_page() if hasattr(instance, "get_current_page") else None
             if current_page and state is not None:
                 # Clear existing elements
                 current_page.layout.elements.clear()
-                
+
                 # Restore elements from serialized state
                 from pyPhotoAlbum.models import ImageData, PlaceholderData, TextBoxData
+
                 for elem_data in state:
-                    elem_type = elem_data.get('type')
-                    if elem_type == 'image':
+                    elem_type = elem_data.get("type")
+                    if elem_type == "image":
                         elem = ImageData()
-                    elif elem_type == 'placeholder':
+                    elif elem_type == "placeholder":
                         elem = PlaceholderData()
-                    elif elem_type == 'textbox':
+                    elif elem_type == "textbox":
                         elem = TextBoxData()
                     else:
                         continue
-                    
+
                     elem.deserialize(elem_data)
                     current_page.layout.add_element(elem)
 
 
-def undoable_operation(capture: str = 'page_elements', description: str = None) -> Callable:
+def undoable_operation(capture: str = "page_elements", description: str = None) -> Callable:
     """
     Convenience function for the UndoableOperation decorator.
 
@@ -343,11 +346,7 @@ class DialogAction:
             self.apply_page_setup(values)
     """
 
-    def __init__(
-        self,
-        dialog_class: type,
-        requires_pages: bool = True
-    ):
+    def __init__(self, dialog_class: type, requires_pages: bool = True):
         """
         Initialize the dialog action decorator.
 
@@ -368,6 +367,7 @@ class DialogAction:
         Returns:
             The decorated function
         """
+
         @wraps(func)
         def wrapper(self_instance, *args, **kwargs):
             # Check preconditions
@@ -376,7 +376,7 @@ class DialogAction:
 
             # Get initial page index if available
             initial_page_index = 0
-            if hasattr(self_instance, '_get_most_visible_page_index'):
+            if hasattr(self_instance, "_get_most_visible_page_index"):
                 initial_page_index = self_instance._get_most_visible_page_index()
 
             # Create and show dialog
@@ -384,17 +384,15 @@ class DialogAction:
 
             # Create dialog
             dialog = self.dialog_class(
-                parent=self_instance,
-                project=self_instance.project,
-                initial_page_index=initial_page_index,
-                **kwargs
+                parent=self_instance, project=self_instance.project, initial_page_index=initial_page_index, **kwargs
             )
 
             # Show dialog and get result
             from PyQt6.QtWidgets import QDialog
+
             if dialog.exec() == QDialog.DialogCode.Accepted:
                 # Get values from dialog
-                if hasattr(dialog, 'get_values'):
+                if hasattr(dialog, "get_values"):
                     values = dialog.get_values()
                     # Call the decorated function with values
                     return func(self_instance, values, *args, **kwargs)
@@ -406,10 +404,7 @@ class DialogAction:
         return wrapper
 
 
-def dialog_action(
-    dialog_class: type,
-    requires_pages: bool = True
-) -> Callable:
+def dialog_action(dialog_class: type, requires_pages: bool = True) -> Callable:
     """
     Convenience function for the DialogAction decorator.
 
diff --git a/pyPhotoAlbum/dialogs/__init__.py b/pyPhotoAlbum/dialogs/__init__.py
index 298a8ac..df46140 100644
--- a/pyPhotoAlbum/dialogs/__init__.py
+++ b/pyPhotoAlbum/dialogs/__init__.py
@@ -7,4 +7,4 @@ UI presentation logic separately from business logic.
 
 from .page_setup_dialog import PageSetupDialog
 
-__all__ = ['PageSetupDialog']
+__all__ = ["PageSetupDialog"]
diff --git a/pyPhotoAlbum/dialogs/page_setup_dialog.py b/pyPhotoAlbum/dialogs/page_setup_dialog.py
index 65f170f..2244870 100644
--- a/pyPhotoAlbum/dialogs/page_setup_dialog.py
+++ b/pyPhotoAlbum/dialogs/page_setup_dialog.py
@@ -8,9 +8,16 @@ separating presentation from business logic.
 import math
 from typing import Optional, Dict, Any
 from PyQt6.QtWidgets import (
-    QDialog, QVBoxLayout, QHBoxLayout, QLabel,
-    QDoubleSpinBox, QSpinBox, QPushButton, QGroupBox,
-    QComboBox, QCheckBox
+    QDialog,
+    QVBoxLayout,
+    QHBoxLayout,
+    QLabel,
+    QDoubleSpinBox,
+    QSpinBox,
+    QPushButton,
+    QGroupBox,
+    QComboBox,
+    QCheckBox,
 )
 from pyPhotoAlbum.project import Project
 
@@ -23,12 +30,7 @@ class PageSetupDialog(QDialog):
     including page size, DPI settings, and cover configuration.
     """
 
-    def __init__(
-        self,
-        parent,
-        project: Project,
-        initial_page_index: int = 0
-    ):
+    def __init__(self, parent, project: Project, initial_page_index: int = 0):
         """
         Initialize the page setup dialog.
 
@@ -105,9 +107,7 @@ class PageSetupDialog(QDialog):
 
         # Cover checkbox
         self.cover_checkbox = QCheckBox("Designate as Cover")
-        self.cover_checkbox.setToolTip(
-            "Mark this page as the book cover with wrap-around front/spine/back"
-        )
+        self.cover_checkbox.setToolTip("Mark this page as the book cover with wrap-around front/spine/back")
         layout.addWidget(self.cover_checkbox)
 
         # Paper thickness
@@ -136,9 +136,7 @@ class PageSetupDialog(QDialog):
 
         # Calculated spine width display
         self.spine_info_label = QLabel()
-        self.spine_info_label.setStyleSheet(
-            "font-size: 9pt; color: #0066cc; padding: 5px;"
-        )
+        self.spine_info_label.setStyleSheet("font-size: 9pt; color: #0066cc; padding: 5px;")
         self.spine_info_label.setWordWrap(True)
         layout.addWidget(self.spine_info_label)
 
@@ -170,9 +168,7 @@ class PageSetupDialog(QDialog):
 
         # Set as default checkbox
         self.set_default_checkbox = QCheckBox("Set as default for new pages")
-        self.set_default_checkbox.setToolTip(
-            "Update project default page size for future pages"
-        )
+        self.set_default_checkbox.setToolTip("Update project default page size for future pages")
         layout.addWidget(self.set_default_checkbox)
 
         group.setLayout(layout)
@@ -248,7 +244,7 @@ class PageSetupDialog(QDialog):
             return
 
         selected_page = self.project.pages[index]
-        is_first_page = (index == 0)
+        is_first_page = index == 0
 
         # Show/hide cover settings based on page selection
         self._cover_group.setVisible(is_first_page)
@@ -265,7 +261,7 @@ class PageSetupDialog(QDialog):
         elif selected_page.is_double_spread:
             display_width = (
                 selected_page.layout.base_width
-                if hasattr(selected_page.layout, 'base_width')
+                if hasattr(selected_page.layout, "base_width")
                 else selected_page.layout.size[0] / 2
             )
         else:
@@ -284,16 +280,12 @@ class PageSetupDialog(QDialog):
         """Update the spine information display."""
         if self.cover_checkbox.isChecked():
             # Calculate spine width with current settings
-            content_pages = sum(
-                p.get_page_count() for p in self.project.pages if not p.is_cover
-            )
+            content_pages = sum(p.get_page_count() for p in self.project.pages if not p.is_cover)
             sheets = math.ceil(content_pages / 4)
             spine_width = sheets * self.thickness_spinbox.value() * 2
 
             page_width = self.project.page_size_mm[0]
-            total_width = (
-                (page_width * 2) + spine_width + (self.bleed_spinbox.value() * 2)
-            )
+            total_width = (page_width * 2) + spine_width + (self.bleed_spinbox.value() * 2)
 
             self.spine_info_label.setText(
                 f"Cover Layout: Front ({page_width:.0f}mm) + "
@@ -317,14 +309,14 @@ class PageSetupDialog(QDialog):
         selected_page = self.project.pages[selected_index]
 
         return {
-            'selected_index': selected_index,
-            'selected_page': selected_page,
-            'is_cover': self.cover_checkbox.isChecked(),
-            'paper_thickness_mm': self.thickness_spinbox.value(),
-            'cover_bleed_mm': self.bleed_spinbox.value(),
-            'width_mm': self.width_spinbox.value(),
-            'height_mm': self.height_spinbox.value(),
-            'working_dpi': self.working_dpi_spinbox.value(),
-            'export_dpi': self.export_dpi_spinbox.value(),
-            'set_as_default': self.set_default_checkbox.isChecked()
+            "selected_index": selected_index,
+            "selected_page": selected_page,
+            "is_cover": self.cover_checkbox.isChecked(),
+            "paper_thickness_mm": self.thickness_spinbox.value(),
+            "cover_bleed_mm": self.bleed_spinbox.value(),
+            "width_mm": self.width_spinbox.value(),
+            "height_mm": self.height_spinbox.value(),
+            "working_dpi": self.working_dpi_spinbox.value(),
+            "export_dpi": self.export_dpi_spinbox.value(),
+            "set_as_default": self.set_default_checkbox.isChecked(),
         }
diff --git a/pyPhotoAlbum/gl_imports.py b/pyPhotoAlbum/gl_imports.py
index 9081c77..be966d5 100644
--- a/pyPhotoAlbum/gl_imports.py
+++ b/pyPhotoAlbum/gl_imports.py
@@ -24,16 +24,13 @@ try:
         GL_LINE_LOOP,
         GL_LINES,
         GL_TRIANGLE_FAN,
-
         # Colors
         glColor3f,
         glColor4f,
-
         # Line state
         glLineWidth,
         glLineStipple,
         GL_LINE_STIPPLE,
-
         # General state
         glEnable,
         glDisable,
@@ -42,7 +39,6 @@ try:
         GL_SRC_ALPHA,
         GL_ONE_MINUS_SRC_ALPHA,
         glBlendFunc,
-
         # Textures
         glGenTextures,
         glBindTexture,
@@ -56,7 +52,6 @@ try:
         GL_TEXTURE_MAG_FILTER,
         GL_LINEAR,
         glTexCoord2f,
-
         # Matrix operations
         glPushMatrix,
         glPopMatrix,
@@ -64,24 +59,22 @@ try:
         glTranslatef,
         glLoadIdentity,
         glRotatef,
-
         # Clear operations
         glClear,
         glClearColor,
         GL_COLOR_BUFFER_BIT,
         GL_DEPTH_BUFFER_BIT,
-
         # Viewport
         glViewport,
         glMatrixMode,
         glOrtho,
         GL_PROJECTION,
         GL_MODELVIEW,
-
         # Info/debug
         glGetString,
         GL_VERSION,
     )
+
     GL_AVAILABLE = True
 
 except ImportError:
diff --git a/pyPhotoAlbum/gl_widget.py b/pyPhotoAlbum/gl_widget.py
index 4c137af..0464374 100644
--- a/pyPhotoAlbum/gl_widget.py
+++ b/pyPhotoAlbum/gl_widget.py
@@ -34,7 +34,7 @@ class GLWidget(
     MouseInteractionMixin,
     UndoableInteractionMixin,
     KeyboardNavigationMixin,
-    QOpenGLWidget
+    QOpenGLWidget,
 ):
     """OpenGL widget for pyPhotoAlbum rendering and user interaction
 
@@ -77,8 +77,8 @@ class GLWidget(
     def _get_project_folder(self):
         """Override AssetPathMixin to access project via main window."""
         main_window = self.window()
-        if hasattr(main_window, 'project') and main_window.project:
-            return getattr(main_window.project, 'folder_path', None)
+        if hasattr(main_window, "project") and main_window.project:
+            return getattr(main_window.project, "folder_path", None)
         return None
 
     def keyPressEvent(self, event):
@@ -86,7 +86,7 @@ class GLWidget(
         if event.key() == Qt.Key.Key_Delete or event.key() == Qt.Key.Key_Backspace:
             if self.selected_element:
                 main_window = self.window()
-                if hasattr(main_window, 'delete_selected_element'):
+                if hasattr(main_window, "delete_selected_element"):
                     main_window.delete_selected_element()
 
         elif event.key() == Qt.Key.Key_Escape:
@@ -99,7 +99,7 @@ class GLWidget(
             if self.selected_element:
                 self.rotation_mode = not self.rotation_mode
                 main_window = self.window()
-                if hasattr(main_window, 'show_status'):
+                if hasattr(main_window, "show_status"):
                     mode_text = "Rotation Mode" if self.rotation_mode else "Move/Resize Mode"
                     main_window.show_status(f"Switched to {mode_text}", 2000)
                 print(f"Rotation mode: {self.rotation_mode}")
diff --git a/pyPhotoAlbum/image_utils.py b/pyPhotoAlbum/image_utils.py
index c863d2d..df6a75f 100644
--- a/pyPhotoAlbum/image_utils.py
+++ b/pyPhotoAlbum/image_utils.py
@@ -13,6 +13,7 @@ from PIL import Image
 # Image Processing Utilities
 # =============================================================================
 
+
 def apply_pil_rotation(image: Image.Image, pil_rotation_90: int) -> Image.Image:
     """
     Apply 90-degree rotation increments to a PIL image.
@@ -48,8 +49,8 @@ def convert_to_rgba(image: Image.Image) -> Image.Image:
     Returns:
         PIL Image in RGBA mode
     """
-    if image.mode != 'RGBA':
-        return image.convert('RGBA')
+    if image.mode != "RGBA":
+        return image.convert("RGBA")
     return image
 
 
@@ -58,7 +59,7 @@ def calculate_center_crop_coords(
     img_height: int,
     target_width: float,
     target_height: float,
-    crop_info: Tuple[float, float, float, float] = (0, 0, 1, 1)
+    crop_info: Tuple[float, float, float, float] = (0, 0, 1, 1),
 ) -> Tuple[float, float, float, float]:
     """
     Calculate texture/crop coordinates for center-crop fitting an image to a target aspect ratio.
@@ -113,10 +114,7 @@ def calculate_center_crop_coords(
     return (tx_min, ty_min, tx_max, ty_max)
 
 
-def crop_image_to_coords(
-    image: Image.Image,
-    coords: Tuple[float, float, float, float]
-) -> Image.Image:
+def crop_image_to_coords(image: Image.Image, coords: Tuple[float, float, float, float]) -> Image.Image:
     """
     Crop an image using normalized texture coordinates.
 
@@ -139,9 +137,7 @@ def crop_image_to_coords(
 
 
 def resize_to_fit(
-    image: Image.Image,
-    max_size: int,
-    resample: Image.Resampling = Image.Resampling.LANCZOS
+    image: Image.Image, max_size: int, resample: Image.Resampling = Image.Resampling.LANCZOS
 ) -> Image.Image:
     """
     Resize image to fit within max_size while preserving aspect ratio.
diff --git a/pyPhotoAlbum/loading_widget.py b/pyPhotoAlbum/loading_widget.py
index a751213..e6f211a 100644
--- a/pyPhotoAlbum/loading_widget.py
+++ b/pyPhotoAlbum/loading_widget.py
@@ -29,7 +29,8 @@ class LoadingWidget(QWidget):
         self.setFixedSize(280, 80)
 
         # Styling
-        self.setStyleSheet("""
+        self.setStyleSheet(
+            """
             QWidget {
                 background-color: rgba(50, 50, 50, 230);
                 border-radius: 8px;
@@ -54,7 +55,8 @@ class LoadingWidget(QWidget):
                     stop:1 rgba(100, 160, 210, 220));
                 border-radius: 3px;
             }
-        """)
+        """
+        )
 
         # Layout
         layout = QVBoxLayout()
diff --git a/pyPhotoAlbum/main.py b/pyPhotoAlbum/main.py
index 7da212e..61989ba 100644
--- a/pyPhotoAlbum/main.py
+++ b/pyPhotoAlbum/main.py
@@ -9,8 +9,14 @@ import sys
 from datetime import datetime
 from pathlib import Path
 from PyQt6.QtWidgets import (
-    QApplication, QMainWindow, QVBoxLayout, QWidget,
-    QStatusBar, QScrollBar, QHBoxLayout, QMessageBox
+    QApplication,
+    QMainWindow,
+    QVBoxLayout,
+    QWidget,
+    QStatusBar,
+    QScrollBar,
+    QHBoxLayout,
+    QMessageBox,
 )
 from PyQt6.QtCore import Qt, QSize, QTimer
 from PyQt6.QtGui import QIcon
@@ -58,12 +64,12 @@ class MainWindow(
 ):
     """
     Main application window using mixin architecture.
-    
+
     This class composes functionality from multiple mixins rather than
     implementing everything directly. The ribbon configuration is
     automatically generated from decorated methods in the mixins.
     """
-    
+
     def __init__(self):
         super().__init__()
 
@@ -85,8 +91,8 @@ class MainWindow(
         self._autosave_timer.start(5 * 60 * 1000)  # 5 minutes in milliseconds
 
         # Add a sample page for demonstration
-        #self._add_sample_page()
-    
+        # self._add_sample_page()
+
     def _init_state(self):
         """Initialize shared application state"""
         # Initialize project
@@ -94,17 +100,18 @@ class MainWindow(
 
         # Set asset resolution context
         from pyPhotoAlbum.models import set_asset_resolution_context
+
         set_asset_resolution_context(self._project.folder_path)
 
         # Initialize template manager
         self._template_manager = TemplateManager()
-    
+
     def _init_ui(self):
         """Initialize user interface"""
         # Basic window setup
         self.setWindowTitle("pyPhotoAlbum")
         self.resize(1200, 800)
-        
+
         # Set window icon
         icon_path = Path(__file__).parent / "icons" / "icon.png"
         print(f"Window icon path: {icon_path}")
@@ -113,20 +120,20 @@ class MainWindow(
             icon = QIcon(str(icon_path))
             print(f"Icon is null: {icon.isNull()}")
             self.setWindowIcon(icon)
-        
+
         # Create main widget with layout
         main_widget = QWidget()
         main_layout = QVBoxLayout()
         main_layout.setContentsMargins(0, 0, 0, 0)
         main_layout.setSpacing(0)
         main_widget.setLayout(main_layout)
-        
+
         # Build ribbon config from decorated methods
         ribbon_config = build_ribbon_config(self.__class__)
-        
+
         # Print summary (for debugging)
         print_ribbon_summary(ribbon_config)
-        
+
         # Create ribbon with auto-generated config
         self.ribbon = RibbonWidget(self, ribbon_config)
         main_layout.addWidget(self.ribbon, 0)
@@ -164,13 +171,13 @@ class MainWindow(
 
         canvas_widget.setLayout(canvas_layout)
         main_layout.addWidget(canvas_widget, 1)
-        
+
         self.setCentralWidget(main_widget)
-        
+
         # Create status bar
         self._status_bar = QStatusBar()
         self.setStatusBar(self._status_bar)
-        
+
         # Register keyboard shortcuts
         self._register_shortcuts()
 
@@ -206,8 +213,8 @@ class MainWindow(
         viewport_width = self._gl_widget.width()
         viewport_height = self._gl_widget.height()
 
-        content_height = bounds['height']
-        content_width = bounds['width']
+        content_height = bounds["height"]
+        content_width = bounds["width"]
 
         # Vertical scrollbar
         # Scrollbar value 0 = top of content
@@ -257,7 +264,7 @@ class MainWindow(
                 print(f"Registered shortcut: {shortcut_str} -> {method_name}")
 
         # Register additional Ctrl+Shift+Z shortcut for redo
-        if hasattr(self, 'redo'):
+        if hasattr(self, "redo"):
             redo_shortcut = QShortcut(QKeySequence("Ctrl+Shift+Z"), self)
             redo_shortcut.activated.connect(self.redo)
             print("Registered shortcut: Ctrl+Shift+Z -> redo")
@@ -265,31 +272,31 @@ class MainWindow(
     def resizeEvent(self, event):
         """Handle window resize to reposition loading widget"""
         super().resizeEvent(event)
-        if hasattr(self, '_loading_widget'):
+        if hasattr(self, "_loading_widget"):
             self._loading_widget.resizeParent()
-    
+
     def _add_sample_page(self):
         """Add a sample page with some elements for demonstration"""
         from pyPhotoAlbum.project import Page
         from pyPhotoAlbum.page_layout import PageLayout, GridLayout
         from pyPhotoAlbum.models import ImageData, TextBoxData, PlaceholderData
-        
+
         # Create a page with project default size
         width_mm, height_mm = self.project.page_size_mm
         page_layout = PageLayout(width=width_mm, height=height_mm)
         grid = GridLayout(rows=2, columns=2, spacing=20.0)
         page_layout.set_grid_layout(grid)
-        
+
         # Add some sample elements (scaled to new default size)
         image = ImageData(image_path="sample.jpg", x=20, y=20, width=50, height=50)
         page_layout.add_element(image)
-        
+
         text_box = TextBoxData(text_content="Sample Text", x=80, y=20, width=50, height=20)
         page_layout.add_element(text_box)
-        
+
         placeholder = PlaceholderData(placeholder_type="image", x=20, y=80, width=50, height=50)
         page_layout.add_element(placeholder)
-        
+
         # Create and add the page
         page = Page(layout=page_layout, page_number=1)
         page.manually_sized = False  # Not manually sized, uses defaults
@@ -315,8 +322,8 @@ class MainWindow(
             return
 
         checkpoint_path, metadata = checkpoint_info
-        project_name = metadata.get('project_name', 'Unknown')
-        timestamp_str = metadata.get('timestamp', 'Unknown time')
+        project_name = metadata.get("project_name", "Unknown")
+        timestamp_str = metadata.get("timestamp", "Unknown time")
 
         # Parse timestamp for better display
         try:
@@ -334,7 +341,7 @@ class MainWindow(
             f"Time: {time_display}\n\n"
             f"Would you like to recover this checkpoint?",
             QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
-            QMessageBox.StandardButton.Yes
+            QMessageBox.StandardButton.Yes,
         )
 
         if reply == QMessageBox.StandardButton.Yes:
@@ -343,7 +350,7 @@ class MainWindow(
 
             if success:
                 # Replace current project with recovered one
-                if hasattr(self, '_project') and self._project:
+                if hasattr(self, "_project") and self._project:
                     self._project.cleanup()
 
                 self._project = result
@@ -365,8 +372,10 @@ class MainWindow(
                 self,
                 "Unsaved Changes",
                 "You have unsaved changes. Would you like to save before exiting?",
-                QMessageBox.StandardButton.Save | QMessageBox.StandardButton.Discard | QMessageBox.StandardButton.Cancel,
                 QMessageBox.StandardButton.Save
+                | QMessageBox.StandardButton.Discard
+                | QMessageBox.StandardButton.Cancel,
+                QMessageBox.StandardButton.Save,
             )
 
             if reply == QMessageBox.StandardButton.Save:
@@ -390,7 +399,7 @@ class MainWindow(
             self.project.cleanup()
 
         # Stop autosave timer
-        if hasattr(self, '_autosave_timer'):
+        if hasattr(self, "_autosave_timer"):
             self._autosave_timer.stop()
 
         # Cleanup old checkpoints
@@ -402,12 +411,12 @@ class MainWindow(
 def main():
     """Application entry point"""
     app = QApplication(sys.argv)
-    
+
     # Set application identity for proper taskbar/window manager integration
     app.setApplicationName("pyPhotoAlbum")
     app.setApplicationDisplayName("pyPhotoAlbum")
     app.setDesktopFileName("pyphotoalbum.desktop")
-    
+
     # Set application icon
     icon_path = Path(__file__).parent / "icons" / "icon.png"
     print(f"Application icon path: {icon_path}")
@@ -416,17 +425,17 @@ def main():
         icon = QIcon(str(icon_path))
         print(f"Icon is null: {icon.isNull()}")
         app.setWindowIcon(icon)
-    
+
     # Enable high DPI scaling
     try:
         app.setAttribute(Qt.ApplicationAttribute.AA_EnableHighDpiScaling, True)
         app.setAttribute(Qt.ApplicationAttribute.AA_UseHighDpiPixmaps, True)
     except AttributeError:
         pass  # Qt version doesn't support these attributes
-    
+
     window = MainWindow()
     window.show()
-    
+
     sys.exit(app.exec())
 
 
diff --git a/pyPhotoAlbum/merge_dialog.py b/pyPhotoAlbum/merge_dialog.py
index 8355c62..2918a65 100644
--- a/pyPhotoAlbum/merge_dialog.py
+++ b/pyPhotoAlbum/merge_dialog.py
@@ -3,9 +3,21 @@ Merge dialog for resolving project conflicts visually
 """
 
 from PyQt6.QtWidgets import (
-    QDialog, QVBoxLayout, QHBoxLayout, QPushButton, QLabel,
-    QListWidget, QListWidgetItem, QSplitter, QWidget, QScrollArea,
-    QRadioButton, QButtonGroup, QTextEdit, QComboBox, QGroupBox
+    QDialog,
+    QVBoxLayout,
+    QHBoxLayout,
+    QPushButton,
+    QLabel,
+    QListWidget,
+    QListWidgetItem,
+    QSplitter,
+    QWidget,
+    QScrollArea,
+    QRadioButton,
+    QButtonGroup,
+    QTextEdit,
+    QComboBox,
+    QGroupBox,
 )
 from PyQt6.QtCore import Qt, QSize, pyqtSignal
 from PyQt6.QtGui import QPixmap, QPainter, QColor, QFont, QPen
@@ -22,10 +34,7 @@ class PagePreviewWidget(QWidget):
         super().__init__(parent)
         self.page_data = page_data
         self.setMinimumSize(200, 280)
-        self.setSizePolicy(
-            self.sizePolicy().Policy.Expanding,
-            self.sizePolicy().Policy.Expanding
-        )
+        self.setSizePolicy(self.sizePolicy().Policy.Expanding, self.sizePolicy().Policy.Expanding)
 
     def paintEvent(self, event):
         """Render the page preview"""
@@ -356,8 +365,4 @@ class MergeDialog(QDialog):
         Returns:
             Merged project data dictionary
         """
-        return self.merge_manager.apply_resolutions(
-            self.our_project_data,
-            self.their_project_data,
-            self.resolutions
-        )
+        return self.merge_manager.apply_resolutions(self.our_project_data, self.their_project_data, self.resolutions)
diff --git a/pyPhotoAlbum/merge_manager.py b/pyPhotoAlbum/merge_manager.py
index 24ae9dc..ec5b617 100644
--- a/pyPhotoAlbum/merge_manager.py
+++ b/pyPhotoAlbum/merge_manager.py
@@ -16,6 +16,7 @@ from datetime import datetime, timezone
 
 class ConflictType(Enum):
     """Types of merge conflicts"""
+
     # Page-level conflicts
     PAGE_MODIFIED_BOTH = "page_modified_both"  # Page modified in both versions
     PAGE_DELETED_ONE = "page_deleted_one"  # Page deleted in one version, modified in other
@@ -31,6 +32,7 @@ class ConflictType(Enum):
 
 class MergeStrategy(Enum):
     """Automatic merge resolution strategies"""
+
     LATEST_WINS = "latest_wins"  # Most recent last_modified wins
     OURS = "ours"  # Always use our version
     THEIRS = "theirs"  # Always use their version
@@ -40,6 +42,7 @@ class MergeStrategy(Enum):
 @dataclass
 class ConflictInfo:
     """Information about a single merge conflict"""
+
     conflict_type: ConflictType
     page_uuid: Optional[str]  # UUID of the page (if page-level conflict)
     element_uuid: Optional[str]  # UUID of the element (if element-level conflict)
@@ -79,9 +82,7 @@ class MergeManager:
         return project_a_id == project_b_id
 
     def detect_conflicts(
-        self,
-        our_project_data: Dict[str, Any],
-        their_project_data: Dict[str, Any]
+        self, our_project_data: Dict[str, Any], their_project_data: Dict[str, Any]
     ) -> List[ConflictInfo]:
         """
         Detect conflicts between two versions of the same project.
@@ -103,16 +104,18 @@ class MergeManager:
 
         return self.conflicts
 
-    def _detect_project_settings_conflicts(
-        self,
-        our_data: Dict[str, Any],
-        their_data: Dict[str, Any]
-    ):
+    def _detect_project_settings_conflicts(self, our_data: Dict[str, Any], their_data: Dict[str, Any]):
         """Detect conflicts in project-level settings."""
         # Settings that can conflict
         settings_keys = [
-            "name", "page_size_mm", "working_dpi", "export_dpi",
-            "has_cover", "paper_thickness_mm", "cover_bleed_mm", "binding_type"
+            "name",
+            "page_size_mm",
+            "working_dpi",
+            "export_dpi",
+            "has_cover",
+            "paper_thickness_mm",
+            "cover_bleed_mm",
+            "binding_type",
         ]
 
         our_modified = our_data.get("last_modified")
@@ -124,20 +127,18 @@ class MergeManager:
 
             # If values differ, it's a conflict
             if our_value != their_value:
-                self.conflicts.append(ConflictInfo(
-                    conflict_type=ConflictType.SETTINGS_MODIFIED_BOTH,
-                    page_uuid=None,
-                    element_uuid=None,
-                    our_version={key: our_value, "last_modified": our_modified},
-                    their_version={key: their_value, "last_modified": their_modified},
-                    description=f"Project setting '{key}' modified in both versions"
-                ))
+                self.conflicts.append(
+                    ConflictInfo(
+                        conflict_type=ConflictType.SETTINGS_MODIFIED_BOTH,
+                        page_uuid=None,
+                        element_uuid=None,
+                        our_version={key: our_value, "last_modified": our_modified},
+                        their_version={key: their_value, "last_modified": their_modified},
+                        description=f"Project setting '{key}' modified in both versions",
+                    )
+                )
 
-    def _detect_page_conflicts(
-        self,
-        our_data: Dict[str, Any],
-        their_data: Dict[str, Any]
-    ):
+    def _detect_page_conflicts(self, our_data: Dict[str, Any], their_data: Dict[str, Any]):
         """Detect conflicts at page level."""
         our_pages = {page["uuid"]: page for page in our_data.get("pages", [])}
         their_pages = {page["uuid"]: page for page in their_data.get("pages", [])}
@@ -164,12 +165,7 @@ class MergeManager:
                 # Unless we deleted it
                 pass
 
-    def _detect_page_modification_conflicts(
-        self,
-        page_uuid: str,
-        our_page: Dict[str, Any],
-        their_page: Dict[str, Any]
-    ):
+    def _detect_page_modification_conflicts(self, page_uuid: str, our_page: Dict[str, Any], their_page: Dict[str, Any]):
         """Detect conflicts in a specific page."""
         our_modified = our_page.get("last_modified")
         their_modified = their_page.get("last_modified")
@@ -180,14 +176,16 @@ class MergeManager:
 
         # Check if one deleted, one modified
         if our_page.get("deleted") != their_page.get("deleted"):
-            self.conflicts.append(ConflictInfo(
-                conflict_type=ConflictType.PAGE_DELETED_ONE,
-                page_uuid=page_uuid,
-                element_uuid=None,
-                our_version=our_page,
-                their_version=their_page,
-                description=f"Page deleted in one version but modified in the other"
-            ))
+            self.conflicts.append(
+                ConflictInfo(
+                    conflict_type=ConflictType.PAGE_DELETED_ONE,
+                    page_uuid=page_uuid,
+                    element_uuid=None,
+                    our_version=our_page,
+                    their_version=their_page,
+                    description=f"Page deleted in one version but modified in the other",
+                )
+            )
             return
 
         # Check page-level properties
@@ -201,24 +199,21 @@ class MergeManager:
         # Only flag as conflict if properties differ AND timestamps are identical
         # (See element conflict detection for detailed explanation of this strategy)
         if page_modified and our_modified == their_modified:
-            self.conflicts.append(ConflictInfo(
-                conflict_type=ConflictType.PAGE_MODIFIED_BOTH,
-                page_uuid=page_uuid,
-                element_uuid=None,
-                our_version=our_page,
-                their_version=their_page,
-                description=f"Page properties modified with same timestamp (possible conflict)"
-            ))
+            self.conflicts.append(
+                ConflictInfo(
+                    conflict_type=ConflictType.PAGE_MODIFIED_BOTH,
+                    page_uuid=page_uuid,
+                    element_uuid=None,
+                    our_version=our_page,
+                    their_version=their_page,
+                    description=f"Page properties modified with same timestamp (possible conflict)",
+                )
+            )
 
         # Check element-level conflicts
         self._detect_element_conflicts(page_uuid, our_page, their_page)
 
-    def _detect_element_conflicts(
-        self,
-        page_uuid: str,
-        our_page: Dict[str, Any],
-        their_page: Dict[str, Any]
-    ):
+    def _detect_element_conflicts(self, page_uuid: str, our_page: Dict[str, Any], their_page: Dict[str, Any]):
         """Detect conflicts in elements within a page."""
         our_layout = our_page.get("layout", {})
         their_layout = their_page.get("layout", {})
@@ -238,16 +233,10 @@ class MergeManager:
                 continue
 
             # Element exists in both - check for modifications
-            self._detect_element_modification_conflicts(
-                page_uuid, elem_uuid, our_elem, their_elem
-            )
+            self._detect_element_modification_conflicts(page_uuid, elem_uuid, our_elem, their_elem)
 
     def _detect_element_modification_conflicts(
-        self,
-        page_uuid: str,
-        elem_uuid: str,
-        our_elem: Dict[str, Any],
-        their_elem: Dict[str, Any]
+        self, page_uuid: str, elem_uuid: str, our_elem: Dict[str, Any], their_elem: Dict[str, Any]
     ):
         """Detect conflicts in a specific element."""
         our_modified = our_elem.get("last_modified")
@@ -259,14 +248,16 @@ class MergeManager:
 
         # Check if one deleted, one modified
         if our_elem.get("deleted") != their_elem.get("deleted"):
-            self.conflicts.append(ConflictInfo(
-                conflict_type=ConflictType.ELEMENT_DELETED_ONE,
-                page_uuid=page_uuid,
-                element_uuid=elem_uuid,
-                our_version=our_elem,
-                their_version=their_elem,
-                description=f"Element deleted in one version but modified in the other"
-            ))
+            self.conflicts.append(
+                ConflictInfo(
+                    conflict_type=ConflictType.ELEMENT_DELETED_ONE,
+                    page_uuid=page_uuid,
+                    element_uuid=elem_uuid,
+                    our_version=our_elem,
+                    their_version=their_elem,
+                    description=f"Element deleted in one version but modified in the other",
+                )
+            )
             return
 
         # Check element properties
@@ -298,22 +289,21 @@ class MergeManager:
             # Properties differ but timestamps match - this is unusual and might indicate
             # that both versions modified it at exactly the same time, or there's data corruption.
             # Flag as conflict to be safe.
-            self.conflicts.append(ConflictInfo(
-                conflict_type=ConflictType.ELEMENT_MODIFIED_BOTH,
-                page_uuid=page_uuid,
-                element_uuid=elem_uuid,
-                our_version=our_elem,
-                their_version=their_elem,
-                description=f"Element modified with same timestamp (possible conflict)"
-            ))
+            self.conflicts.append(
+                ConflictInfo(
+                    conflict_type=ConflictType.ELEMENT_MODIFIED_BOTH,
+                    page_uuid=page_uuid,
+                    element_uuid=elem_uuid,
+                    our_version=our_elem,
+                    their_version=their_elem,
+                    description=f"Element modified with same timestamp (possible conflict)",
+                )
+            )
 
         # Note: If timestamps differ, we assume one version modified it and the other didn't.
         # The _merge_non_conflicting_changes method will automatically use the newer version.
 
-    def auto_resolve_conflicts(
-        self,
-        strategy: MergeStrategy = MergeStrategy.LATEST_WINS
-    ) -> Dict[str, Any]:
+    def auto_resolve_conflicts(self, strategy: MergeStrategy = MergeStrategy.LATEST_WINS) -> Dict[str, Any]:
         """
         Automatically resolve conflicts based on a strategy.
 
@@ -353,10 +343,7 @@ class MergeManager:
         return None
 
     def apply_resolutions(
-        self,
-        our_project_data: Dict[str, Any],
-        their_project_data: Dict[str, Any],
-        resolutions: Dict[int, str]
+        self, our_project_data: Dict[str, Any], their_project_data: Dict[str, Any], resolutions: Dict[int, str]
     ) -> Dict[str, Any]:
         """
         Apply conflict resolutions to create merged project.
@@ -415,20 +402,12 @@ class MergeManager:
                             break
                     break
 
-    def _merge_non_conflicting_changes(
-        self,
-        merged_data: Dict[str, Any],
-        their_data: Dict[str, Any]
-    ):
+    def _merge_non_conflicting_changes(self, merged_data: Dict[str, Any], their_data: Dict[str, Any]):
         """Add non-conflicting pages and elements from their version."""
         self._add_missing_pages(merged_data, their_data)
         self._merge_page_elements(merged_data, their_data)
 
-    def _add_missing_pages(
-        self,
-        merged_data: Dict[str, Any],
-        their_data: Dict[str, Any]
-    ):
+    def _add_missing_pages(self, merged_data: Dict[str, Any], their_data: Dict[str, Any]):
         """Add pages that exist only in their version."""
         our_page_uuids = {page["uuid"] for page in merged_data.get("pages", [])}
 
@@ -436,11 +415,7 @@ class MergeManager:
             if their_page["uuid"] not in our_page_uuids:
                 merged_data["pages"].append(their_page)
 
-    def _merge_page_elements(
-        self,
-        merged_data: Dict[str, Any],
-        their_data: Dict[str, Any]
-    ):
+    def _merge_page_elements(self, merged_data: Dict[str, Any], their_data: Dict[str, Any]):
         """For pages that exist in both versions, merge their elements."""
         their_pages = {page["uuid"]: page for page in their_data.get("pages", [])}
 
@@ -449,25 +424,15 @@ class MergeManager:
             if not their_page:
                 continue
 
-            our_elements = {
-                elem["uuid"]: elem
-                for elem in our_page.get("layout", {}).get("elements", [])
-            }
+            our_elements = {elem["uuid"]: elem for elem in our_page.get("layout", {}).get("elements", [])}
 
             for their_elem in their_page.get("layout", {}).get("elements", []):
                 self._merge_element(
-                    our_page=our_page,
-                    page_uuid=our_page["uuid"],
-                    their_elem=their_elem,
-                    our_elements=our_elements
+                    our_page=our_page, page_uuid=our_page["uuid"], their_elem=their_elem, our_elements=our_elements
                 )
 
     def _merge_element(
-        self,
-        our_page: Dict[str, Any],
-        page_uuid: str,
-        their_elem: Dict[str, Any],
-        our_elements: Dict[str, Any]
+        self, our_page: Dict[str, Any], page_uuid: str, their_elem: Dict[str, Any], our_elements: Dict[str, Any]
     ):
         """Merge a single element from their version into our page."""
         elem_uuid = their_elem["uuid"]
@@ -486,17 +451,10 @@ class MergeManager:
 
     def _is_element_in_conflict(self, elem_uuid: str, page_uuid: str) -> bool:
         """Check if element was part of a conflict that was already resolved."""
-        return any(
-            c.element_uuid == elem_uuid and c.page_uuid == page_uuid
-            for c in self.conflicts
-        )
+        return any(c.element_uuid == elem_uuid and c.page_uuid == page_uuid for c in self.conflicts)
 
     def _merge_by_timestamp(
-        self,
-        our_page: Dict[str, Any],
-        elem_uuid: str,
-        their_elem: Dict[str, Any],
-        our_elem: Dict[str, Any]
+        self, our_page: Dict[str, Any], elem_uuid: str, their_elem: Dict[str, Any], our_elem: Dict[str, Any]
     ):
         """Use the more recently modified version of an element."""
         our_modified = our_elem.get("last_modified")
@@ -513,10 +471,7 @@ class MergeManager:
                 break
 
 
-def concatenate_projects(
-    project_a_data: Dict[str, Any],
-    project_b_data: Dict[str, Any]
-) -> Dict[str, Any]:
+def concatenate_projects(project_a_data: Dict[str, Any], project_b_data: Dict[str, Any]) -> Dict[str, Any]:
     """
     Concatenate two projects with different project_ids.
 
@@ -542,6 +497,8 @@ def concatenate_projects(
     # Update last_modified to now
     merged_data["last_modified"] = datetime.now(timezone.utc).isoformat()
 
-    print(f"Concatenated projects: {len(project_a_data.get('pages', []))} + {len(project_b_data.get('pages', []))} = {len(merged_data['pages'])} pages")
+    print(
+        f"Concatenated projects: {len(project_a_data.get('pages', []))} + {len(project_b_data.get('pages', []))} = {len(merged_data['pages'])} pages"
+    )
 
     return merged_data
diff --git a/pyPhotoAlbum/mixins/__init__.py b/pyPhotoAlbum/mixins/__init__.py
index 35c8f9b..2c2696a 100644
--- a/pyPhotoAlbum/mixins/__init__.py
+++ b/pyPhotoAlbum/mixins/__init__.py
@@ -5,4 +5,4 @@ Mixin modules for pyPhotoAlbum
 from pyPhotoAlbum.mixins.base import ApplicationStateMixin
 from pyPhotoAlbum.mixins.dialog_mixin import DialogMixin
 
-__all__ = ['ApplicationStateMixin', 'DialogMixin']
+__all__ = ["ApplicationStateMixin", "DialogMixin"]
diff --git a/pyPhotoAlbum/mixins/asset_drop.py b/pyPhotoAlbum/mixins/asset_drop.py
index 3408103..651322b 100644
--- a/pyPhotoAlbum/mixins/asset_drop.py
+++ b/pyPhotoAlbum/mixins/asset_drop.py
@@ -14,7 +14,7 @@ class AssetDropMixin:
     or updating ImageData elements.
     """
 
-    IMAGE_EXTENSIONS = ['.jpg', '.jpeg', '.png', '.gif', '.bmp', '.tiff', '.webp']
+    IMAGE_EXTENSIONS = [".jpg", ".jpeg", ".png", ".gif", ".bmp", ".tiff", ".webp"]
 
     def dragEnterEvent(self, event):
         """Handle drag enter events"""
@@ -66,7 +66,7 @@ class AssetDropMixin:
     def _handle_drop_on_element(self, image_path, target_element):
         """Handle dropping an image onto an existing element"""
         main_window = self.window()
-        if not (hasattr(main_window, 'project') and main_window.project):
+        if not (hasattr(main_window, "project") and main_window.project):
             return
 
         try:
@@ -89,7 +89,7 @@ class AssetDropMixin:
             y=placeholder.position[1],
             width=placeholder.size[0],
             height=placeholder.size[1],
-            z_index=placeholder.z_index
+            z_index=placeholder.z_index,
         )
 
         if not main_window.project.pages:
@@ -104,7 +104,7 @@ class AssetDropMixin:
     def _handle_drop_on_empty_space(self, image_path, x, y):
         """Handle dropping an image onto empty space"""
         main_window = self.window()
-        if not (hasattr(main_window, 'project') and main_window.project and main_window.project.pages):
+        if not (hasattr(main_window, "project") and main_window.project and main_window.project.pages):
             return
 
         target_page, page_index, page_renderer = self._get_page_at(x, y)
@@ -120,8 +120,7 @@ class AssetDropMixin:
             img_width, img_height = self._calculate_image_dimensions(full_asset_path)
 
             self._add_new_image_to_page(
-                asset_path, target_page, page_index, page_renderer,
-                x, y, img_width, img_height, main_window
+                asset_path, target_page, page_index, page_renderer, x, y, img_width, img_height, main_window
             )
         except Exception as e:
             print(f"Error importing dropped image: {e}")
@@ -138,27 +137,18 @@ class AssetDropMixin:
         # Fallback dimensions if image cannot be read
         return 200, 150
 
-    def _add_new_image_to_page(self, asset_path, target_page, page_index,
-                                page_renderer, x, y, img_width, img_height, main_window):
+    def _add_new_image_to_page(
+        self, asset_path, target_page, page_index, page_renderer, x, y, img_width, img_height, main_window
+    ):
         """Add a new image element to the target page (asset already imported)"""
         if page_index >= 0:
             self.current_page_index = page_index
 
         page_local_x, page_local_y = page_renderer.screen_to_page(x, y)
 
-        new_image = ImageData(
-            image_path=asset_path,
-            x=page_local_x,
-            y=page_local_y,
-            width=img_width,
-            height=img_height
-        )
+        new_image = ImageData(image_path=asset_path, x=page_local_x, y=page_local_y, width=img_width, height=img_height)
 
-        cmd = AddElementCommand(
-            target_page.layout,
-            new_image,
-            asset_manager=main_window.project.asset_manager
-        )
+        cmd = AddElementCommand(target_page.layout, new_image, asset_manager=main_window.project.asset_manager)
         main_window.project.history.execute(cmd)
 
         print(f"Added new image to page {page_index + 1} at ({page_local_x:.1f}, {page_local_y:.1f}): {asset_path}")
diff --git a/pyPhotoAlbum/mixins/asset_path.py b/pyPhotoAlbum/mixins/asset_path.py
index 6a082e1..00c0483 100644
--- a/pyPhotoAlbum/mixins/asset_path.py
+++ b/pyPhotoAlbum/mixins/asset_path.py
@@ -63,6 +63,6 @@ class AssetPathMixin:
         Override this method if the project is accessed differently.
         Default implementation uses self.project.folder_path.
         """
-        if hasattr(self, 'project') and self.project:
-            return getattr(self.project, 'folder_path', None)
+        if hasattr(self, "project") and self.project:
+            return getattr(self.project, "folder_path", None)
         return None
diff --git a/pyPhotoAlbum/mixins/async_loading.py b/pyPhotoAlbum/mixins/async_loading.py
index e03f929..abfa696 100644
--- a/pyPhotoAlbum/mixins/async_loading.py
+++ b/pyPhotoAlbum/mixins/async_loading.py
@@ -48,13 +48,13 @@ class AsyncLoadingMixin:
         """Cleanup async loading components."""
         logger.info("Cleaning up async loading system...")
 
-        if hasattr(self, 'async_image_loader'):
+        if hasattr(self, "async_image_loader"):
             self.async_image_loader.stop()
 
-        if hasattr(self, 'async_pdf_generator'):
+        if hasattr(self, "async_pdf_generator"):
             self.async_pdf_generator.stop()
 
-        if hasattr(self, 'image_cache'):
+        if hasattr(self, "image_cache"):
             self.image_cache.clear()
 
         logger.info("Async loading system cleaned up")
@@ -70,7 +70,7 @@ class AsyncLoadingMixin:
         """
         logger.debug(f"Image loaded callback: {path}")
 
-        if user_data and hasattr(user_data, '_on_async_image_loaded'):
+        if user_data and hasattr(user_data, "_on_async_image_loaded"):
             user_data._on_async_image_loaded(image)
 
         # Trigger re-render to show newly loaded image
@@ -87,7 +87,7 @@ class AsyncLoadingMixin:
         """
         logger.warning(f"Image load failed: {path} - {error_msg}")
 
-        if user_data and hasattr(user_data, '_on_async_image_load_failed'):
+        if user_data and hasattr(user_data, "_on_async_image_load_failed"):
             user_data._on_async_image_load_failed(error_msg)
 
     def _on_pdf_progress(self, current: int, total: int, message: str):
@@ -102,7 +102,7 @@ class AsyncLoadingMixin:
         logger.debug(f"PDF progress: {current}/{total} - {message}")
 
         # Update progress dialog if it exists
-        if hasattr(self, '_pdf_progress_dialog') and self._pdf_progress_dialog:
+        if hasattr(self, "_pdf_progress_dialog") and self._pdf_progress_dialog:
             self._pdf_progress_dialog.setValue(current)
             self._pdf_progress_dialog.setLabelText(message)
 
@@ -117,19 +117,16 @@ class AsyncLoadingMixin:
         logger.info(f"PDF export complete: success={success}, warnings={len(warnings)}")
 
         # Close progress dialog
-        if hasattr(self, '_pdf_progress_dialog') and self._pdf_progress_dialog:
+        if hasattr(self, "_pdf_progress_dialog") and self._pdf_progress_dialog:
             self._pdf_progress_dialog.close()
             self._pdf_progress_dialog = None
 
         # Show completion message
         main_window = self.window()
-        if hasattr(main_window, 'show_status'):
+        if hasattr(main_window, "show_status"):
             if success:
                 if warnings:
-                    main_window.show_status(
-                        f"PDF exported successfully with {len(warnings)} warnings",
-                        5000
-                    )
+                    main_window.show_status(f"PDF exported successfully with {len(warnings)} warnings", 5000)
                 else:
                     main_window.show_status("PDF exported successfully", 3000)
             else:
@@ -145,13 +142,13 @@ class AsyncLoadingMixin:
         logger.error(f"PDF export failed: {error_msg}")
 
         # Close progress dialog
-        if hasattr(self, '_pdf_progress_dialog') and self._pdf_progress_dialog:
+        if hasattr(self, "_pdf_progress_dialog") and self._pdf_progress_dialog:
             self._pdf_progress_dialog.close()
             self._pdf_progress_dialog = None
 
         # Show error message
         main_window = self.window()
-        if hasattr(main_window, 'show_status'):
+        if hasattr(main_window, "show_status"):
             main_window.show_status(f"PDF export failed: {error_msg}", 5000)
 
     def request_image_load(self, image_data, priority: LoadPriority = LoadPriority.NORMAL):
@@ -162,7 +159,7 @@ class AsyncLoadingMixin:
             image_data: ImageData element to load
             priority: Load priority level
         """
-        if not hasattr(self, 'async_image_loader'):
+        if not hasattr(self, "async_image_loader"):
             logger.warning("Async image loader not initialized")
             return
 
@@ -188,7 +185,7 @@ class AsyncLoadingMixin:
             Path(image_full_path),
             priority=priority,
             target_size=target_size,
-            user_data=image_data  # Pass element for callback
+            user_data=image_data,  # Pass element for callback
         )
 
     def export_pdf_async(self, project, output_path: str, export_dpi: int = 300):
@@ -200,7 +197,7 @@ class AsyncLoadingMixin:
             output_path: Output PDF file path
             export_dpi: Export DPI (default 300)
         """
-        if not hasattr(self, 'async_pdf_generator'):
+        if not hasattr(self, "async_pdf_generator"):
             logger.warning("Async PDF generator not initialized")
             return False
 
@@ -208,18 +205,9 @@ class AsyncLoadingMixin:
         from PyQt6.QtWidgets import QProgressDialog
         from PyQt6.QtCore import Qt
 
-        total_pages = sum(
-            1 if page.is_cover else (2 if page.is_double_spread else 1)
-            for page in project.pages
-        )
+        total_pages = sum(1 if page.is_cover else (2 if page.is_double_spread else 1) for page in project.pages)
 
-        self._pdf_progress_dialog = QProgressDialog(
-            "Exporting to PDF...",
-            "Cancel",
-            0,
-            total_pages,
-            self
-        )
+        self._pdf_progress_dialog = QProgressDialog("Exporting to PDF...", "Cancel", 0, total_pages, self)
         self._pdf_progress_dialog.setWindowModality(Qt.WindowModality.WindowModal)
         self._pdf_progress_dialog.setWindowTitle("PDF Export")
         self._pdf_progress_dialog.canceled.connect(self._on_pdf_cancel)
@@ -232,17 +220,17 @@ class AsyncLoadingMixin:
         """Handle PDF export cancellation."""
         logger.info("User requested PDF export cancellation")
 
-        if hasattr(self, 'async_pdf_generator'):
+        if hasattr(self, "async_pdf_generator"):
             self.async_pdf_generator.cancel_export()
 
     def get_async_stats(self) -> dict:
         """Get async loading system statistics."""
         stats = {}
 
-        if hasattr(self, 'async_image_loader'):
-            stats['image_loader'] = self.async_image_loader.get_stats()
+        if hasattr(self, "async_image_loader"):
+            stats["image_loader"] = self.async_image_loader.get_stats()
 
-        if hasattr(self, 'async_pdf_generator'):
-            stats['pdf_generator'] = self.async_pdf_generator.get_stats()
+        if hasattr(self, "async_pdf_generator"):
+            stats["pdf_generator"] = self.async_pdf_generator.get_stats()
 
         return stats
diff --git a/pyPhotoAlbum/mixins/base.py b/pyPhotoAlbum/mixins/base.py
index 63be57a..1b044c0 100644
--- a/pyPhotoAlbum/mixins/base.py
+++ b/pyPhotoAlbum/mixins/base.py
@@ -9,50 +9,50 @@ from PyQt6.QtWidgets import QStatusBar, QMessageBox
 class ApplicationStateMixin:
     """
     Base mixin providing access to shared application state.
-    
+
     This mixin provides properties and helper methods for accessing
     core application objects that are shared across all operation mixins.
-    
+
     Required attributes (must be set by MainWindow):
         _project: Project instance
         _gl_widget: GLWidget instance
         _status_bar: QStatusBar instance
         _template_manager: TemplateManager instance
     """
-    
+
     @property
     def project(self):
         """Access to current project"""
-        if not hasattr(self, '_project'):
+        if not hasattr(self, "_project"):
             raise AttributeError("MainWindow must set _project attribute")
         return self._project
-    
+
     @project.setter
     def project(self, value):
         """Set the current project"""
         self._project = value
-    
+
     @property
     def gl_widget(self):
         """Access to GL rendering widget"""
-        if not hasattr(self, '_gl_widget'):
+        if not hasattr(self, "_gl_widget"):
             raise AttributeError("MainWindow must set _gl_widget attribute")
         return self._gl_widget
-    
+
     @property
     def status_bar(self) -> QStatusBar:
         """Access to status bar"""
-        if not hasattr(self, '_status_bar'):
+        if not hasattr(self, "_status_bar"):
             raise AttributeError("MainWindow must set _status_bar attribute")
         return self._status_bar
-    
+
     @property
     def template_manager(self):
         """Access to template manager"""
-        if not hasattr(self, '_template_manager'):
+        if not hasattr(self, "_template_manager"):
             raise AttributeError("MainWindow must set _template_manager attribute")
         return self._template_manager
-    
+
     # Common helper methods
 
     def _get_most_visible_page_index(self):
@@ -62,7 +62,7 @@ class ApplicationStateMixin:
         Returns:
             int: Index of the most visible page
         """
-        if not hasattr(self.gl_widget, '_page_renderers') or not self.gl_widget._page_renderers:
+        if not hasattr(self.gl_widget, "_page_renderers") or not self.gl_widget._page_renderers:
             return self.gl_widget.current_page_index
 
         # Get viewport dimensions
@@ -70,7 +70,7 @@ class ApplicationStateMixin:
         viewport_center_y = viewport_height / 2
 
         # Find which page's center is closest to viewport center
-        min_distance = float('inf')
+        min_distance = float("inf")
         best_page_index = self.gl_widget.current_page_index
 
         for renderer, page in self.gl_widget._page_renderers:
@@ -107,109 +107,106 @@ class ApplicationStateMixin:
             return self.project.pages[index]
 
         return None
-    
+
     def get_current_page_index(self) -> int:
         """
         Get current page index.
-        
+
         Returns:
             Current page index, or -1 if no page
         """
         if not self.project or not self.project.pages:
             return -1
         return self.gl_widget.current_page_index
-    
+
     def show_status(self, message: str, timeout: int = 2000):
         """
         Show message in status bar.
-        
+
         Args:
             message: Message to display
             timeout: Display duration in milliseconds
         """
         if self.status_bar:
             self.status_bar.showMessage(message, timeout)
-    
+
     def show_error(self, title: str, message: str):
         """
         Show error dialog.
-        
+
         Args:
             title: Dialog title
             message: Error message
         """
         QMessageBox.critical(self, title, message)
-    
+
     def show_warning(self, title: str, message: str):
         """
         Show warning dialog.
-        
+
         Args:
             title: Dialog title
             message: Warning message
         """
         QMessageBox.warning(self, title, message)
-    
+
     def show_info(self, title: str, message: str):
         """
         Show information dialog.
-        
+
         Args:
             title: Dialog title
             message: Information message
         """
         QMessageBox.information(self, title, message)
-    
+
     def require_page(self, show_warning: bool = True) -> bool:
         """
         Check if a page is available and optionally show warning.
-        
+
         Args:
             show_warning: Whether to show warning dialog if no page exists
-            
+
         Returns:
             True if page exists, False otherwise
         """
         current_page = self.get_current_page()
-        
+
         if current_page is None:
             if show_warning:
                 self.show_warning("No Page", "Please create a page first.")
             return False
-        
+
         return True
-    
+
     def require_selection(self, min_count: int = 1, show_warning: bool = True) -> bool:
         """
         Check if required number of elements are selected.
-        
+
         Args:
             min_count: Minimum number of selected elements required
             show_warning: Whether to show warning dialog if requirement not met
-            
+
         Returns:
             True if requirements met, False otherwise
         """
         selected_count = len(self.gl_widget.selected_elements)
-        
+
         if selected_count < min_count:
             if show_warning:
                 if min_count == 1:
                     self.show_info("No Selection", "Please select an element.")
                 else:
-                    self.show_info(
-                        "Selection Required",
-                        f"Please select at least {min_count} elements."
-                    )
+                    self.show_info("Selection Required", f"Please select at least {min_count} elements.")
             return False
-        
+
         return True
-    
+
     def update_view(self):
         """Trigger GL widget update to refresh the view"""
         if self.gl_widget:
             self.gl_widget.update()
 
             # Update scrollbars to reflect new content
-            if hasattr(self, 'update_scrollbars'):
+            if hasattr(self, "update_scrollbars"):
                 self.update_scrollbars()
diff --git a/pyPhotoAlbum/mixins/dialog_mixin.py b/pyPhotoAlbum/mixins/dialog_mixin.py
index 114ac81..2def4a9 100644
--- a/pyPhotoAlbum/mixins/dialog_mixin.py
+++ b/pyPhotoAlbum/mixins/dialog_mixin.py
@@ -16,12 +16,7 @@ class DialogMixin:
     making it easier to create, test, and maintain complex dialogs.
     """
 
-    def create_dialog(
-        self,
-        dialog_class: type,
-        title: Optional[str] = None,
-        **kwargs
-    ) -> Optional[Any]:
+    def create_dialog(self, dialog_class: type, title: Optional[str] = None, **kwargs) -> Optional[Any]:
         """
         Create and show a dialog, handling the result.
 
@@ -43,18 +38,13 @@ class DialogMixin:
         # Show dialog and handle result
         if dialog.exec() == QDialog.DialogCode.Accepted:
             # Check if dialog has a get_values method
-            if hasattr(dialog, 'get_values'):
+            if hasattr(dialog, "get_values"):
                 return dialog.get_values()
             return True
 
         return None
 
-    def show_dialog(
-        self,
-        dialog_class: type,
-        on_accept: Optional[Callable] = None,
-        **kwargs
-    ) -> bool:
+    def show_dialog(self, dialog_class: type, on_accept: Optional[Callable] = None, **kwargs) -> bool:
         """
         Show a dialog and execute callback on acceptance.
 
diff --git a/pyPhotoAlbum/mixins/element_manipulation.py b/pyPhotoAlbum/mixins/element_manipulation.py
index 1a014fa..6cde1e7 100644
--- a/pyPhotoAlbum/mixins/element_manipulation.py
+++ b/pyPhotoAlbum/mixins/element_manipulation.py
@@ -27,11 +27,7 @@ class ElementManipulationMixin:
         self.rotation_snap_angle: int = 15  # Default snap angle in degrees
 
         # Snap state tracking
-        self.snap_state = {
-            'is_snapped': False,
-            'last_position': None,
-            'last_size': None
-        }
+        self.snap_state = {"is_snapped": False, "last_position": None, "last_size": None}
 
     def _resize_element(self, dx: float, dy: float):
         """
@@ -49,7 +45,7 @@ class ElementManipulationMixin:
 
         # Get the snapping system from the element's parent page
         main_window = self.window()
-        if not hasattr(self.selected_element, '_parent_page'):
+        if not hasattr(self.selected_element, "_parent_page"):
             self._resize_element_no_snap(dx, dy)
             return
 
@@ -62,6 +58,7 @@ class ElementManipulationMixin:
 
         # Apply snapping to resize
         from pyPhotoAlbum.snapping import SnapResizeParams
+
         params = SnapResizeParams(
             position=self.resize_start_pos,
             size=self.resize_start_size,
@@ -70,7 +67,7 @@ class ElementManipulationMixin:
             resize_handle=self.resize_handle,
             page_size=page_size,
             dpi=dpi,
-            project=main_window.project
+            project=main_window.project,
         )
         new_pos, new_size = snap_sys.snap_resize(params)
 
@@ -100,16 +97,16 @@ class ElementManipulationMixin:
         start_x, start_y = self.resize_start_pos
         start_w, start_h = self.resize_start_size
 
-        if self.resize_handle == 'nw':
+        if self.resize_handle == "nw":
             self.selected_element.position = (start_x + dx, start_y + dy)
             self.selected_element.size = (start_w - dx, start_h - dy)
-        elif self.resize_handle == 'ne':
+        elif self.resize_handle == "ne":
             self.selected_element.position = (start_x, start_y + dy)
             self.selected_element.size = (start_w + dx, start_h - dy)
-        elif self.resize_handle == 'sw':
+        elif self.resize_handle == "sw":
             self.selected_element.position = (start_x + dx, start_y)
             self.selected_element.size = (start_w - dx, start_h + dy)
-        elif self.resize_handle == 'se':
+        elif self.resize_handle == "se":
             self.selected_element.size = (start_w + dx, start_h + dy)
 
         # Ensure minimum size
@@ -121,7 +118,9 @@ class ElementManipulationMixin:
             w, _ = self.selected_element.size
             self.selected_element.size = (w, min_size)
 
-    def _transfer_element_to_page(self, element, source_page, target_page, mouse_x: float, mouse_y: float, target_renderer):
+    def _transfer_element_to_page(
+        self, element, source_page, target_page, mouse_x: float, mouse_y: float, target_renderer
+    ):
         """
         Transfer an element from one page to another during drag operation.
 
diff --git a/pyPhotoAlbum/mixins/element_selection.py b/pyPhotoAlbum/mixins/element_selection.py
index 6766a3a..8f671c3 100644
--- a/pyPhotoAlbum/mixins/element_selection.py
+++ b/pyPhotoAlbum/mixins/element_selection.py
@@ -54,7 +54,7 @@ class ElementSelectionMixin:
         Returns:
             BaseLayoutElement or None: The topmost element at the position, or None
         """
-        if not hasattr(self, '_page_renderers') or not self._page_renderers:
+        if not hasattr(self, "_page_renderers") or not self._page_renderers:
             return None
 
         # Check each page from top to bottom (reverse z-order)
@@ -96,11 +96,11 @@ class ElementSelectionMixin:
             return None
 
         main_window = self.window()
-        if not hasattr(main_window, 'project') or not main_window.project or not main_window.project.pages:
+        if not hasattr(main_window, "project") or not main_window.project or not main_window.project.pages:
             return None
 
         # Get the PageRenderer for this element (stored when element was selected)
-        if not hasattr(self.selected_element, '_page_renderer'):
+        if not hasattr(self.selected_element, "_page_renderer"):
             return None
 
         renderer = self.selected_element._page_renderer
@@ -117,10 +117,10 @@ class ElementSelectionMixin:
 
         # Check handles (no rotation transformation needed - images are already rotated)
         handles = {
-            'nw': (ex - handle_size/2, ey - handle_size/2),
-            'ne': (ex + ew - handle_size/2, ey - handle_size/2),
-            'sw': (ex - handle_size/2, ey + eh - handle_size/2),
-            'se': (ex + ew - handle_size/2, ey + eh - handle_size/2),
+            "nw": (ex - handle_size / 2, ey - handle_size / 2),
+            "ne": (ex + ew - handle_size / 2, ey - handle_size / 2),
+            "sw": (ex - handle_size / 2, ey + eh - handle_size / 2),
+            "se": (ex + ew - handle_size / 2, ey + eh - handle_size / 2),
         }
 
         for name, (hx, hy) in handles.items():
diff --git a/pyPhotoAlbum/mixins/interaction_command_builders.py b/pyPhotoAlbum/mixins/interaction_command_builders.py
index e1e8c57..b1d4687 100644
--- a/pyPhotoAlbum/mixins/interaction_command_builders.py
+++ b/pyPhotoAlbum/mixins/interaction_command_builders.py
@@ -59,7 +59,7 @@ class MoveCommandBuilder(CommandBuilder):
 
     def can_build(self, element: BaseLayoutElement, start_state: dict, **kwargs) -> bool:
         """Check if position changed significantly."""
-        old_pos = start_state.get('position')
+        old_pos = start_state.get("position")
         if old_pos is None:
             return False
 
@@ -68,7 +68,7 @@ class MoveCommandBuilder(CommandBuilder):
 
     def build(self, element: BaseLayoutElement, start_state: dict, **kwargs) -> Optional[Any]:
         """Build a MoveElementCommand."""
-        old_pos = start_state.get('position')
+        old_pos = start_state.get("position")
         if old_pos is None:
             return None
 
@@ -79,6 +79,7 @@ class MoveCommandBuilder(CommandBuilder):
             return None
 
         from pyPhotoAlbum.commands import MoveElementCommand
+
         command = MoveElementCommand(element, old_pos, new_pos)
 
         self.log_command("Move", f"{old_pos} → {new_pos}")
@@ -90,8 +91,8 @@ class ResizeCommandBuilder(CommandBuilder):
 
     def can_build(self, element: BaseLayoutElement, start_state: dict, **kwargs) -> bool:
         """Check if position or size changed significantly."""
-        old_pos = start_state.get('position')
-        old_size = start_state.get('size')
+        old_pos = start_state.get("position")
+        old_size = start_state.get("size")
 
         if old_pos is None or old_size is None:
             return False
@@ -106,8 +107,8 @@ class ResizeCommandBuilder(CommandBuilder):
 
     def build(self, element: BaseLayoutElement, start_state: dict, **kwargs) -> Optional[Any]:
         """Build a ResizeElementCommand."""
-        old_pos = start_state.get('position')
-        old_size = start_state.get('size')
+        old_pos = start_state.get("position")
+        old_size = start_state.get("size")
 
         if old_pos is None or old_size is None:
             return None
@@ -119,6 +120,7 @@ class ResizeCommandBuilder(CommandBuilder):
             return None
 
         from pyPhotoAlbum.commands import ResizeElementCommand
+
         command = ResizeElementCommand(element, old_pos, old_size, new_pos, new_size)
 
         self.log_command("Resize", f"{old_size} → {new_size}")
@@ -130,7 +132,7 @@ class RotateCommandBuilder(CommandBuilder):
 
     def can_build(self, element: BaseLayoutElement, start_state: dict, **kwargs) -> bool:
         """Check if rotation changed significantly."""
-        old_rotation = start_state.get('rotation')
+        old_rotation = start_state.get("rotation")
         if old_rotation is None:
             return False
 
@@ -139,7 +141,7 @@ class RotateCommandBuilder(CommandBuilder):
 
     def build(self, element: BaseLayoutElement, start_state: dict, **kwargs) -> Optional[Any]:
         """Build a RotateElementCommand."""
-        old_rotation = start_state.get('rotation')
+        old_rotation = start_state.get("rotation")
         if old_rotation is None:
             return None
 
@@ -150,6 +152,7 @@ class RotateCommandBuilder(CommandBuilder):
             return None
 
         from pyPhotoAlbum.commands import RotateElementCommand
+
         command = RotateElementCommand(element, old_rotation, new_rotation)
 
         self.log_command("Rotation", f"{old_rotation:.1f}° → {new_rotation:.1f}°")
@@ -166,7 +169,7 @@ class ImagePanCommandBuilder(CommandBuilder):
         if not isinstance(element, ImageData):
             return False
 
-        old_crop = start_state.get('crop_info')
+        old_crop = start_state.get("crop_info")
         if old_crop is None:
             return False
 
@@ -181,7 +184,7 @@ class ImagePanCommandBuilder(CommandBuilder):
         if not isinstance(element, ImageData):
             return None
 
-        old_crop = start_state.get('crop_info')
+        old_crop = start_state.get("crop_info")
         if old_crop is None:
             return None
 
@@ -193,6 +196,7 @@ class ImagePanCommandBuilder(CommandBuilder):
             return None
 
         from pyPhotoAlbum.commands import AdjustImageCropCommand
+
         command = AdjustImageCropCommand(element, old_crop, new_crop)
 
         self.log_command("Image pan", f"{old_crop} → {new_crop}")
diff --git a/pyPhotoAlbum/mixins/interaction_command_factory.py b/pyPhotoAlbum/mixins/interaction_command_factory.py
index 46958a0..693b465 100644
--- a/pyPhotoAlbum/mixins/interaction_command_factory.py
+++ b/pyPhotoAlbum/mixins/interaction_command_factory.py
@@ -12,7 +12,7 @@ from .interaction_command_builders import (
     MoveCommandBuilder,
     ResizeCommandBuilder,
     RotateCommandBuilder,
-    ImagePanCommandBuilder
+    ImagePanCommandBuilder,
 )
 
 
@@ -31,10 +31,10 @@ class InteractionCommandFactory:
 
     def _register_default_builders(self):
         """Register the default command builders."""
-        self.register_builder('move', MoveCommandBuilder())
-        self.register_builder('resize', ResizeCommandBuilder())
-        self.register_builder('rotate', RotateCommandBuilder())
-        self.register_builder('image_pan', ImagePanCommandBuilder())
+        self.register_builder("move", MoveCommandBuilder())
+        self.register_builder("resize", ResizeCommandBuilder())
+        self.register_builder("rotate", RotateCommandBuilder())
+        self.register_builder("image_pan", ImagePanCommandBuilder())
 
     def register_builder(self, interaction_type: str, builder: CommandBuilder):
         """
@@ -46,11 +46,9 @@ class InteractionCommandFactory:
         """
         self._builders[interaction_type] = builder
 
-    def create_command(self,
-                      interaction_type: str,
-                      element: BaseLayoutElement,
-                      start_state: dict,
-                      **kwargs) -> Optional[Any]:
+    def create_command(
+        self, interaction_type: str, element: BaseLayoutElement, start_state: dict, **kwargs
+    ) -> Optional[Any]:
         """
         Create a command based on interaction type and state changes.
 
@@ -91,13 +89,15 @@ class InteractionState:
     the code more maintainable.
     """
 
-    def __init__(self,
-                 element: Optional[BaseLayoutElement] = None,
-                 interaction_type: Optional[str] = None,
-                 position: Optional[tuple] = None,
-                 size: Optional[tuple] = None,
-                 rotation: Optional[float] = None,
-                 crop_info: Optional[tuple] = None):
+    def __init__(
+        self,
+        element: Optional[BaseLayoutElement] = None,
+        interaction_type: Optional[str] = None,
+        position: Optional[tuple] = None,
+        size: Optional[tuple] = None,
+        rotation: Optional[float] = None,
+        crop_info: Optional[tuple] = None,
+    ):
         """
         Initialize interaction state.
 
@@ -125,13 +125,13 @@ class InteractionState:
         """
         state = {}
         if self.position is not None:
-            state['position'] = self.position
+            state["position"] = self.position
         if self.size is not None:
-            state['size'] = self.size
+            state["size"] = self.size
         if self.rotation is not None:
-            state['rotation'] = self.rotation
+            state["rotation"] = self.rotation
         if self.crop_info is not None:
-            state['crop_info'] = self.crop_info
+            state["crop_info"] = self.crop_info
         return state
 
     def is_valid(self) -> bool:
diff --git a/pyPhotoAlbum/mixins/interaction_undo.py b/pyPhotoAlbum/mixins/interaction_undo.py
index 2eb20eb..01ead49 100644
--- a/pyPhotoAlbum/mixins/interaction_undo.py
+++ b/pyPhotoAlbum/mixins/interaction_undo.py
@@ -10,12 +10,12 @@ from .interaction_command_factory import InteractionCommandFactory, InteractionS
 class UndoableInteractionMixin:
     """
     Mixin providing automatic undo/redo for interactive mouse operations.
-    
+
     This mixin tracks the state of elements before interactive operations
     (move, resize, rotate) and automatically creates appropriate Command
     objects when the interaction completes.
     """
-    
+
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
 
@@ -24,7 +24,7 @@ class UndoableInteractionMixin:
 
         # Interaction state tracking
         self._interaction_state = InteractionState()
-    
+
     def _begin_move(self, element: BaseLayoutElement):
         """
         Begin tracking a move operation.
@@ -33,9 +33,9 @@ class UndoableInteractionMixin:
             element: The element being moved
         """
         self._interaction_state.element = element
-        self._interaction_state.interaction_type = 'move'
+        self._interaction_state.interaction_type = "move"
         self._interaction_state.position = element.position
-    
+
     def _begin_resize(self, element: BaseLayoutElement):
         """
         Begin tracking a resize operation.
@@ -44,10 +44,10 @@ class UndoableInteractionMixin:
             element: The element being resized
         """
         self._interaction_state.element = element
-        self._interaction_state.interaction_type = 'resize'
+        self._interaction_state.interaction_type = "resize"
         self._interaction_state.position = element.position
         self._interaction_state.size = element.size
-    
+
     def _begin_rotate(self, element: BaseLayoutElement):
         """
         Begin tracking a rotate operation.
@@ -56,9 +56,9 @@ class UndoableInteractionMixin:
             element: The element being rotated
         """
         self._interaction_state.element = element
-        self._interaction_state.interaction_type = 'rotate'
+        self._interaction_state.interaction_type = "rotate"
         self._interaction_state.rotation = element.rotation
-    
+
     def _begin_image_pan(self, element):
         """
         Begin tracking an image pan operation.
@@ -67,13 +67,14 @@ class UndoableInteractionMixin:
             element: The ImageData element being panned
         """
         from pyPhotoAlbum.models import ImageData
+
         if not isinstance(element, ImageData):
             return
 
         self._interaction_state.element = element
-        self._interaction_state.interaction_type = 'image_pan'
+        self._interaction_state.interaction_type = "image_pan"
         self._interaction_state.crop_info = element.crop_info
-    
+
     def _end_interaction(self):
         """
         End the current interaction and create appropriate undo/redo command.
@@ -88,7 +89,7 @@ class UndoableInteractionMixin:
 
         # Get main window to access project history
         main_window = self.window()
-        if not hasattr(main_window, 'project'):
+        if not hasattr(main_window, "project"):
             self._clear_interaction_state()
             return
 
@@ -96,7 +97,7 @@ class UndoableInteractionMixin:
         command = self._command_factory.create_command(
             interaction_type=self._interaction_state.interaction_type,
             element=self._interaction_state.element,
-            start_state=self._interaction_state.to_dict()
+            start_state=self._interaction_state.to_dict(),
         )
 
         # Execute the command through history if one was created
@@ -105,11 +106,11 @@ class UndoableInteractionMixin:
 
         # Clear interaction state
         self._clear_interaction_state()
-    
+
     def _clear_interaction_state(self):
         """Clear all interaction tracking state"""
         self._interaction_state.clear()
-    
+
     def _cancel_interaction(self):
         """Cancel the current interaction without creating a command"""
         self._clear_interaction_state()
diff --git a/pyPhotoAlbum/mixins/interaction_validators.py b/pyPhotoAlbum/mixins/interaction_validators.py
index d13163c..2bfe66b 100644
--- a/pyPhotoAlbum/mixins/interaction_validators.py
+++ b/pyPhotoAlbum/mixins/interaction_validators.py
@@ -16,6 +16,7 @@ def significant_change(threshold: float = 0.1):
     Returns:
         None if change is insignificant, otherwise returns the command builder result
     """
+
     def decorator(func):
         @wraps(func)
         def wrapper(*args, **kwargs):
@@ -23,7 +24,9 @@ def significant_change(threshold: float = 0.1):
             if result is None:
                 return None
             return result
+
         return wrapper
+
     return decorator
 
 
@@ -31,9 +34,9 @@ class ChangeValidator:
     """Validates whether changes are significant enough to create commands."""
 
     @staticmethod
-    def position_changed(old_pos: Optional[Tuple[float, float]],
-                        new_pos: Optional[Tuple[float, float]],
-                        threshold: float = 0.1) -> bool:
+    def position_changed(
+        old_pos: Optional[Tuple[float, float]], new_pos: Optional[Tuple[float, float]], threshold: float = 0.1
+    ) -> bool:
         """Check if position changed significantly."""
         if old_pos is None or new_pos is None:
             return False
@@ -43,9 +46,9 @@ class ChangeValidator:
         return dx > threshold or dy > threshold
 
     @staticmethod
-    def size_changed(old_size: Optional[Tuple[float, float]],
-                    new_size: Optional[Tuple[float, float]],
-                    threshold: float = 0.1) -> bool:
+    def size_changed(
+        old_size: Optional[Tuple[float, float]], new_size: Optional[Tuple[float, float]], threshold: float = 0.1
+    ) -> bool:
         """Check if size changed significantly."""
         if old_size is None or new_size is None:
             return False
@@ -55,9 +58,7 @@ class ChangeValidator:
         return dw > threshold or dh > threshold
 
     @staticmethod
-    def rotation_changed(old_rotation: Optional[float],
-                        new_rotation: Optional[float],
-                        threshold: float = 0.1) -> bool:
+    def rotation_changed(old_rotation: Optional[float], new_rotation: Optional[float], threshold: float = 0.1) -> bool:
         """Check if rotation changed significantly."""
         if old_rotation is None or new_rotation is None:
             return False
@@ -65,9 +66,11 @@ class ChangeValidator:
         return abs(new_rotation - old_rotation) > threshold
 
     @staticmethod
-    def crop_changed(old_crop: Optional[Tuple[float, float, float, float]],
-                    new_crop: Optional[Tuple[float, float, float, float]],
-                    threshold: float = 0.001) -> bool:
+    def crop_changed(
+        old_crop: Optional[Tuple[float, float, float, float]],
+        new_crop: Optional[Tuple[float, float, float, float]],
+        threshold: float = 0.001,
+    ) -> bool:
         """Check if crop info changed significantly."""
         if old_crop is None or new_crop is None:
             return False
@@ -85,8 +88,7 @@ class InteractionChangeDetector:
         self.threshold = threshold
         self.validator = ChangeValidator()
 
-    def detect_position_change(self, old_pos: Tuple[float, float],
-                              new_pos: Tuple[float, float]) -> Optional[dict]:
+    def detect_position_change(self, old_pos: Tuple[float, float], new_pos: Tuple[float, float]) -> Optional[dict]:
         """
         Detect position change and return change info.
 
@@ -97,14 +99,13 @@ class InteractionChangeDetector:
             return None
 
         return {
-            'old_position': old_pos,
-            'new_position': new_pos,
-            'delta_x': new_pos[0] - old_pos[0],
-            'delta_y': new_pos[1] - old_pos[1]
+            "old_position": old_pos,
+            "new_position": new_pos,
+            "delta_x": new_pos[0] - old_pos[0],
+            "delta_y": new_pos[1] - old_pos[1],
         }
 
-    def detect_size_change(self, old_size: Tuple[float, float],
-                          new_size: Tuple[float, float]) -> Optional[dict]:
+    def detect_size_change(self, old_size: Tuple[float, float], new_size: Tuple[float, float]) -> Optional[dict]:
         """
         Detect size change and return change info.
 
@@ -115,14 +116,13 @@ class InteractionChangeDetector:
             return None
 
         return {
-            'old_size': old_size,
-            'new_size': new_size,
-            'delta_width': new_size[0] - old_size[0],
-            'delta_height': new_size[1] - old_size[1]
+            "old_size": old_size,
+            "new_size": new_size,
+            "delta_width": new_size[0] - old_size[0],
+            "delta_height": new_size[1] - old_size[1],
         }
 
-    def detect_rotation_change(self, old_rotation: float,
-                               new_rotation: float) -> Optional[dict]:
+    def detect_rotation_change(self, old_rotation: float, new_rotation: float) -> Optional[dict]:
         """
         Detect rotation change and return change info.
 
@@ -132,14 +132,11 @@ class InteractionChangeDetector:
         if not self.validator.rotation_changed(old_rotation, new_rotation, self.threshold):
             return None
 
-        return {
-            'old_rotation': old_rotation,
-            'new_rotation': new_rotation,
-            'delta_angle': new_rotation - old_rotation
-        }
+        return {"old_rotation": old_rotation, "new_rotation": new_rotation, "delta_angle": new_rotation - old_rotation}
 
-    def detect_crop_change(self, old_crop: Tuple[float, float, float, float],
-                          new_crop: Tuple[float, float, float, float]) -> Optional[dict]:
+    def detect_crop_change(
+        self, old_crop: Tuple[float, float, float, float], new_crop: Tuple[float, float, float, float]
+    ) -> Optional[dict]:
         """
         Detect crop change and return change info.
 
@@ -149,8 +146,4 @@ class InteractionChangeDetector:
         if not self.validator.crop_changed(old_crop, new_crop, threshold=0.001):
             return None
 
-        return {
-            'old_crop': old_crop,
-            'new_crop': new_crop,
-            'delta': tuple(new_crop[i] - old_crop[i] for i in range(4))
-        }
+        return {"old_crop": old_crop, "new_crop": new_crop, "delta": tuple(new_crop[i] - old_crop[i] for i in range(4))}
diff --git a/pyPhotoAlbum/mixins/keyboard_navigation.py b/pyPhotoAlbum/mixins/keyboard_navigation.py
index 848b6e0..4366b5a 100644
--- a/pyPhotoAlbum/mixins/keyboard_navigation.py
+++ b/pyPhotoAlbum/mixins/keyboard_navigation.py
@@ -16,7 +16,7 @@ class KeyboardNavigationMixin:
     def _navigate_to_next_page(self):
         """Navigate to the next page using Page Down key"""
         main_window = self.window()
-        if not hasattr(main_window, 'project') or not main_window.project or not main_window.project.pages:
+        if not hasattr(main_window, "project") or not main_window.project or not main_window.project.pages:
             return
 
         current_index = main_window._get_most_visible_page_index()
@@ -24,14 +24,14 @@ class KeyboardNavigationMixin:
             next_page = main_window.project.pages[current_index + 1]
             self._scroll_to_page(next_page, current_index + 1)
 
-            if hasattr(main_window, 'show_status'):
+            if hasattr(main_window, "show_status"):
                 page_name = main_window.project.get_page_display_name(next_page)
                 main_window.show_status(f"Navigated to {page_name}", 2000)
 
     def _navigate_to_previous_page(self):
         """Navigate to the previous page using Page Up key"""
         main_window = self.window()
-        if not hasattr(main_window, 'project') or not main_window.project or not main_window.project.pages:
+        if not hasattr(main_window, "project") or not main_window.project or not main_window.project.pages:
             return
 
         current_index = main_window._get_most_visible_page_index()
@@ -39,7 +39,7 @@ class KeyboardNavigationMixin:
             prev_page = main_window.project.pages[current_index - 1]
             self._scroll_to_page(prev_page, current_index - 1)
 
-            if hasattr(main_window, 'show_status'):
+            if hasattr(main_window, "show_status"):
                 page_name = main_window.project.get_page_display_name(prev_page)
                 main_window.show_status(f"Navigated to {page_name}", 2000)
 
@@ -52,7 +52,7 @@ class KeyboardNavigationMixin:
             page_index: The index of the page in the project
         """
         main_window = self.window()
-        if not hasattr(main_window, 'project'):
+        if not hasattr(main_window, "project"):
             return
 
         dpi = main_window.project.working_dpi
@@ -79,14 +79,14 @@ class KeyboardNavigationMixin:
         self.pan_offset[1] = target_pan_y
 
         # Clamp pan offset to content bounds
-        if hasattr(self, 'clamp_pan_offset'):
+        if hasattr(self, "clamp_pan_offset"):
             self.clamp_pan_offset()
 
         self.update()
 
         # Update scrollbars if available
         main_window = self.window()
-        if hasattr(main_window, 'update_scrollbars'):
+        if hasattr(main_window, "update_scrollbars"):
             main_window.update_scrollbars()
 
     def _move_viewport_with_arrow_keys(self, key):
@@ -109,14 +109,14 @@ class KeyboardNavigationMixin:
             self.pan_offset[0] -= move_amount
 
         # Clamp pan offset to content bounds
-        if hasattr(self, 'clamp_pan_offset'):
+        if hasattr(self, "clamp_pan_offset"):
             self.clamp_pan_offset()
 
         self.update()
 
         # Update scrollbars if available
         main_window = self.window()
-        if hasattr(main_window, 'update_scrollbars'):
+        if hasattr(main_window, "update_scrollbars"):
             main_window.update_scrollbars()
 
     def _move_selected_elements_with_arrow_keys(self, key):
@@ -127,7 +127,7 @@ class KeyboardNavigationMixin:
             key: The Qt key code (Up, Down, Left, Right)
         """
         main_window = self.window()
-        if not hasattr(main_window, 'project'):
+        if not hasattr(main_window, "project"):
             return
 
         # Movement amount in mm
@@ -151,7 +151,7 @@ class KeyboardNavigationMixin:
             new_y = current_y + dy
 
             # Apply snapping if element has a parent page
-            if hasattr(element, '_parent_page') and element._parent_page:
+            if hasattr(element, "_parent_page") and element._parent_page:
                 page = element._parent_page
                 snap_sys = page.layout.snapping_system
                 page_size = page.layout.size
@@ -162,7 +162,7 @@ class KeyboardNavigationMixin:
                     size=element.size,
                     page_size=page_size,
                     dpi=dpi,
-                    project=main_window.project
+                    project=main_window.project,
                 )
                 element.position = snapped_pos
             else:
@@ -170,7 +170,7 @@ class KeyboardNavigationMixin:
 
         self.update()
 
-        if hasattr(main_window, 'show_status'):
+        if hasattr(main_window, "show_status"):
             count = len(self.selected_elements)
             elem_text = "element" if count == 1 else "elements"
             main_window.show_status(f"Moved {count} {elem_text}", 1000)
diff --git a/pyPhotoAlbum/mixins/mouse_interaction.py b/pyPhotoAlbum/mixins/mouse_interaction.py
index dc3128a..a8af0b8 100644
--- a/pyPhotoAlbum/mixins/mouse_interaction.py
+++ b/pyPhotoAlbum/mixins/mouse_interaction.py
@@ -66,7 +66,9 @@ class MouseInteractionMixin:
 
             element = self._get_element_at(x, y)
             if element:
-                print(f"DEBUG: Clicked on element: {element}, ctrl_pressed: {ctrl_pressed}, shift_pressed: {shift_pressed}")
+                print(
+                    f"DEBUG: Clicked on element: {element}, ctrl_pressed: {ctrl_pressed}, shift_pressed: {shift_pressed}"
+                )
                 # Check if Ctrl is pressed and element is ImageData - enter image pan mode
                 if ctrl_pressed and isinstance(element, ImageData) and not self.rotation_mode:
                     # Enter image pan mode - pan image within frame
@@ -129,7 +131,7 @@ class MouseInteractionMixin:
             self.pan_offset[1] += dy
 
             # Clamp pan offset to content bounds
-            if hasattr(self, 'clamp_pan_offset'):
+            if hasattr(self, "clamp_pan_offset"):
                 self.clamp_pan_offset()
 
             self.drag_start_pos = (x, y)
@@ -137,7 +139,7 @@ class MouseInteractionMixin:
 
             # Update scrollbars if available
             main_window = self.window()
-            if hasattr(main_window, 'update_scrollbars'):
+            if hasattr(main_window, "update_scrollbars"):
                 main_window.update_scrollbars()
 
             return
@@ -152,7 +154,7 @@ class MouseInteractionMixin:
 
             elif self.rotation_mode:
                 # Rotation mode
-                if not hasattr(self.selected_element, '_page_renderer'):
+                if not hasattr(self.selected_element, "_page_renderer"):
                     return
 
                 renderer = self.selected_element._page_renderer
@@ -173,7 +175,7 @@ class MouseInteractionMixin:
                 self.selected_element.rotation = angle
 
                 main_window = self.window()
-                if hasattr(main_window, 'show_status'):
+                if hasattr(main_window, "show_status"):
                     main_window.show_status(f"Rotation: {angle:.1f}°", 100)
 
             elif self.resize_handle:
@@ -189,11 +191,13 @@ class MouseInteractionMixin:
                 # Move mode
                 current_page, current_page_index, current_renderer = self._get_page_at(x, y)
 
-                if current_page and hasattr(self.selected_element, '_parent_page'):
+                if current_page and hasattr(self.selected_element, "_parent_page"):
                     source_page = self.selected_element._parent_page
 
                     if current_page is not source_page:
-                        self._transfer_element_to_page(self.selected_element, source_page, current_page, x, y, current_renderer)
+                        self._transfer_element_to_page(
+                            self.selected_element, source_page, current_page, x, y, current_renderer
+                        )
                     else:
                         total_dx = (x - self.drag_start_pos[0]) / self.zoom_level
                         total_dy = (y - self.drag_start_pos[1]) / self.zoom_level
@@ -211,7 +215,7 @@ class MouseInteractionMixin:
                             size=self.selected_element.size,
                             page_size=page_size,
                             dpi=dpi,
-                            project=main_window.project
+                            project=main_window.project,
                         )
 
                         self.selected_element.position = snapped_pos
@@ -238,11 +242,7 @@ class MouseInteractionMixin:
             self.rotation_start_angle = None
             self.image_pan_mode = False
             self.image_pan_start_crop = None
-            self.snap_state = {
-                'is_snapped': False,
-                'last_position': None,
-                'last_size': None
-            }
+            self.snap_state = {"is_snapped": False, "last_position": None, "last_size": None}
             self.setCursor(Qt.CursorShape.ArrowCursor)
 
         elif event.button() == Qt.MouseButton.MiddleButton:
@@ -257,6 +257,7 @@ class MouseInteractionMixin:
             element = self._get_element_at(x, y)
 
             from pyPhotoAlbum.models import TextBoxData
+
             if isinstance(element, TextBoxData):
                 self._edit_text_element(element)
                 return
@@ -293,23 +294,20 @@ class MouseInteractionMixin:
                 if self.is_dragging and self.drag_start_pos:
                     pan_delta_x = self.pan_offset[0] - old_pan_x
                     pan_delta_y = self.pan_offset[1] - old_pan_y
-                    self.drag_start_pos = (
-                        self.drag_start_pos[0] + pan_delta_x,
-                        self.drag_start_pos[1] + pan_delta_y
-                    )
+                    self.drag_start_pos = (self.drag_start_pos[0] + pan_delta_x, self.drag_start_pos[1] + pan_delta_y)
 
                 # Clamp pan offset to content bounds
-                if hasattr(self, 'clamp_pan_offset'):
+                if hasattr(self, "clamp_pan_offset"):
                     self.clamp_pan_offset()
 
                 self.update()
 
                 main_window = self.window()
-                if hasattr(main_window, 'status_bar'):
+                if hasattr(main_window, "status_bar"):
                     main_window.status_bar.showMessage(f"Zoom: {int(self.zoom_level * 100)}%", 2000)
 
                 # Update scrollbars if available
-                if hasattr(main_window, 'update_scrollbars'):
+                if hasattr(main_window, "update_scrollbars"):
                     main_window.update_scrollbars()
         else:
             # Regular wheel: Vertical scroll
@@ -318,22 +316,19 @@ class MouseInteractionMixin:
             self.pan_offset[1] += scroll_amount
 
             # Clamp pan offset to content bounds
-            if hasattr(self, 'clamp_pan_offset'):
+            if hasattr(self, "clamp_pan_offset"):
                 self.clamp_pan_offset()
 
             # If dragging, adjust drag_start_pos to account for pan_offset change
             if self.is_dragging and self.drag_start_pos:
                 pan_delta_y = self.pan_offset[1] - old_pan_y
-                self.drag_start_pos = (
-                    self.drag_start_pos[0],
-                    self.drag_start_pos[1] + pan_delta_y
-                )
+                self.drag_start_pos = (self.drag_start_pos[0], self.drag_start_pos[1] + pan_delta_y)
 
             self.update()
 
             # Update scrollbars if available
             main_window = self.window()
-            if hasattr(main_window, 'update_scrollbars'):
+            if hasattr(main_window, "update_scrollbars"):
                 main_window.update_scrollbars()
 
     def _edit_text_element(self, text_element):
@@ -344,9 +339,9 @@ class MouseInteractionMixin:
         if dialog.exec() == TextEditDialog.DialogCode.Accepted:
             values = dialog.get_values()
 
-            text_element.text_content = values['text_content']
-            text_element.font_settings = values['font_settings']
-            text_element.alignment = values['alignment']
+            text_element.text_content = values["text_content"]
+            text_element.font_settings = values["font_settings"]
+            text_element.alignment = values["alignment"]
 
             self.update()
 
diff --git a/pyPhotoAlbum/mixins/operations/__init__.py b/pyPhotoAlbum/mixins/operations/__init__.py
index 479a7a7..b597bd1 100644
--- a/pyPhotoAlbum/mixins/operations/__init__.py
+++ b/pyPhotoAlbum/mixins/operations/__init__.py
@@ -15,15 +15,15 @@ from pyPhotoAlbum.mixins.operations.zorder_ops import ZOrderOperationsMixin
 from pyPhotoAlbum.mixins.operations.merge_ops import MergeOperationsMixin
 
 __all__ = [
-    'FileOperationsMixin',
-    'EditOperationsMixin',
-    'ElementOperationsMixin',
-    'PageOperationsMixin',
-    'TemplateOperationsMixin',
-    'ViewOperationsMixin',
-    'AlignmentOperationsMixin',
-    'DistributionOperationsMixin',
-    'SizeOperationsMixin',
-    'ZOrderOperationsMixin',
-    'MergeOperationsMixin',
+    "FileOperationsMixin",
+    "EditOperationsMixin",
+    "ElementOperationsMixin",
+    "PageOperationsMixin",
+    "TemplateOperationsMixin",
+    "ViewOperationsMixin",
+    "AlignmentOperationsMixin",
+    "DistributionOperationsMixin",
+    "SizeOperationsMixin",
+    "ZOrderOperationsMixin",
+    "MergeOperationsMixin",
 ]
diff --git a/pyPhotoAlbum/mixins/operations/alignment_ops.py b/pyPhotoAlbum/mixins/operations/alignment_ops.py
index 5d0a6ca..ce4c744 100644
--- a/pyPhotoAlbum/mixins/operations/alignment_ops.py
+++ b/pyPhotoAlbum/mixins/operations/alignment_ops.py
@@ -9,130 +9,130 @@ from pyPhotoAlbum.commands import AlignElementsCommand, ResizeElementsCommand
 
 class AlignmentOperationsMixin:
     """Mixin providing element alignment operations"""
-    
+
     def _get_selected_elements_list(self):
         """Get list of selected elements for alignment operations"""
         return list(self.gl_widget.selected_elements) if self.gl_widget.selected_elements else []
-    
+
     @ribbon_action(
         label="Align Left",
         tooltip="Align selected elements to the left",
         tab="Arrange",
         group="Align",
         requires_selection=True,
-        min_selection=2
+        min_selection=2,
     )
     def align_left(self):
         """Align selected elements to the left"""
         elements = self._get_selected_elements_list()
         if not self.require_selection(min_count=2):
             return
-        
+
         changes = AlignmentManager.align_left(elements)
         if changes:
             cmd = AlignElementsCommand(changes)
             self.project.history.execute(cmd)
             self.update_view()
             self.show_status(f"Aligned {len(elements)} elements to left", 2000)
-    
+
     @ribbon_action(
         label="Align Right",
         tooltip="Align selected elements to the right",
         tab="Arrange",
         group="Align",
         requires_selection=True,
-        min_selection=2
+        min_selection=2,
     )
     def align_right(self):
         """Align selected elements to the right"""
         elements = self._get_selected_elements_list()
         if not self.require_selection(min_count=2):
             return
-        
+
         changes = AlignmentManager.align_right(elements)
         if changes:
             cmd = AlignElementsCommand(changes)
             self.project.history.execute(cmd)
             self.update_view()
             self.show_status(f"Aligned {len(elements)} elements to right", 2000)
-    
+
     @ribbon_action(
         label="Align Top",
         tooltip="Align selected elements to the top",
         tab="Arrange",
         group="Align",
         requires_selection=True,
-        min_selection=2
+        min_selection=2,
     )
     def align_top(self):
         """Align selected elements to the top"""
         elements = self._get_selected_elements_list()
         if not self.require_selection(min_count=2):
             return
-        
+
         changes = AlignmentManager.align_top(elements)
         if changes:
             cmd = AlignElementsCommand(changes)
             self.project.history.execute(cmd)
             self.update_view()
             self.show_status(f"Aligned {len(elements)} elements to top", 2000)
-    
+
     @ribbon_action(
         label="Align Bottom",
         tooltip="Align selected elements to the bottom",
         tab="Arrange",
         group="Align",
         requires_selection=True,
-        min_selection=2
+        min_selection=2,
     )
     def align_bottom(self):
         """Align selected elements to the bottom"""
         elements = self._get_selected_elements_list()
         if not self.require_selection(min_count=2):
             return
-        
+
         changes = AlignmentManager.align_bottom(elements)
         if changes:
             cmd = AlignElementsCommand(changes)
             self.project.history.execute(cmd)
             self.update_view()
             self.show_status(f"Aligned {len(elements)} elements to bottom", 2000)
-    
+
     @ribbon_action(
         label="Align H-Center",
         tooltip="Align selected elements to horizontal center",
         tab="Arrange",
         group="Align",
         requires_selection=True,
-        min_selection=2
+        min_selection=2,
     )
     def align_horizontal_center(self):
         """Align selected elements to horizontal center"""
         elements = self._get_selected_elements_list()
         if not self.require_selection(min_count=2):
             return
-        
+
         changes = AlignmentManager.align_horizontal_center(elements)
         if changes:
             cmd = AlignElementsCommand(changes)
             self.project.history.execute(cmd)
             self.update_view()
             self.show_status(f"Aligned {len(elements)} elements to horizontal center", 2000)
-    
+
     @ribbon_action(
         label="Align V-Center",
         tooltip="Align selected elements to vertical center",
         tab="Arrange",
         group="Align",
         requires_selection=True,
-        min_selection=2
+        min_selection=2,
     )
     def align_vertical_center(self):
         """Align selected elements to vertical center"""
         elements = self._get_selected_elements_list()
         if not self.require_selection(min_count=2):
             return
-        
+
         changes = AlignmentManager.align_vertical_center(elements)
         if changes:
             cmd = AlignElementsCommand(changes)
@@ -146,7 +146,7 @@ class AlignmentOperationsMixin:
         tab="Arrange",
         group="Size",
         requires_selection=True,
-        min_selection=1
+        min_selection=1,
     )
     def maximize_pattern(self):
         """Maximize selected elements until they are close to borders or each other"""
diff --git a/pyPhotoAlbum/mixins/operations/distribution_ops.py b/pyPhotoAlbum/mixins/operations/distribution_ops.py
index b1f377c..7a07da2 100644
--- a/pyPhotoAlbum/mixins/operations/distribution_ops.py
+++ b/pyPhotoAlbum/mixins/operations/distribution_ops.py
@@ -9,88 +9,88 @@ from pyPhotoAlbum.commands import AlignElementsCommand
 
 class DistributionOperationsMixin:
     """Mixin providing element distribution and spacing operations"""
-    
+
     def _get_selected_elements_list(self):
         """Get list of selected elements for distribution operations"""
         return list(self.gl_widget.selected_elements) if self.gl_widget.selected_elements else []
-    
+
     @ribbon_action(
         label="Distribute H",
         tooltip="Distribute selected elements evenly horizontally",
         tab="Arrange",
         group="Distribute",
         requires_selection=True,
-        min_selection=3
+        min_selection=3,
     )
     def distribute_horizontally(self):
         """Distribute selected elements evenly horizontally"""
         elements = self._get_selected_elements_list()
         if not self.require_selection(min_count=3):
             return
-        
+
         changes = AlignmentManager.distribute_horizontally(elements)
         if changes:
             cmd = AlignElementsCommand(changes)
             self.project.history.execute(cmd)
             self.update_view()
             self.show_status(f"Distributed {len(elements)} elements horizontally", 2000)
-    
+
     @ribbon_action(
         label="Distribute V",
         tooltip="Distribute selected elements evenly vertically",
         tab="Arrange",
         group="Distribute",
         requires_selection=True,
-        min_selection=3
+        min_selection=3,
     )
     def distribute_vertically(self):
         """Distribute selected elements evenly vertically"""
         elements = self._get_selected_elements_list()
         if not self.require_selection(min_count=3):
             return
-        
+
         changes = AlignmentManager.distribute_vertically(elements)
         if changes:
             cmd = AlignElementsCommand(changes)
             self.project.history.execute(cmd)
             self.update_view()
             self.show_status(f"Distributed {len(elements)} elements vertically", 2000)
-    
+
     @ribbon_action(
         label="Space H",
         tooltip="Space selected elements equally horizontally",
         tab="Arrange",
         group="Distribute",
         requires_selection=True,
-        min_selection=3
+        min_selection=3,
     )
     def space_horizontally(self):
         """Space selected elements equally horizontally"""
         elements = self._get_selected_elements_list()
         if not self.require_selection(min_count=3):
             return
-        
+
         changes = AlignmentManager.space_horizontally(elements)
         if changes:
             cmd = AlignElementsCommand(changes)
             self.project.history.execute(cmd)
             self.update_view()
             self.show_status(f"Spaced {len(elements)} elements horizontally", 2000)
-    
+
     @ribbon_action(
         label="Space V",
         tooltip="Space selected elements equally vertically",
         tab="Arrange",
         group="Distribute",
         requires_selection=True,
-        min_selection=3
+        min_selection=3,
     )
     def space_vertically(self):
         """Space selected elements equally vertically"""
         elements = self._get_selected_elements_list()
         if not self.require_selection(min_count=3):
             return
-        
+
         changes = AlignmentManager.space_vertically(elements)
         if changes:
             cmd = AlignElementsCommand(changes)
diff --git a/pyPhotoAlbum/mixins/operations/edit_ops.py b/pyPhotoAlbum/mixins/operations/edit_ops.py
index fdfc920..6dfd3c6 100644
--- a/pyPhotoAlbum/mixins/operations/edit_ops.py
+++ b/pyPhotoAlbum/mixins/operations/edit_ops.py
@@ -8,14 +8,8 @@ from pyPhotoAlbum.commands import DeleteElementCommand, RotateElementCommand
 
 class EditOperationsMixin:
     """Mixin providing edit-related operations"""
-    
-    @ribbon_action(
-        label="Undo",
-        tooltip="Undo last action (Ctrl+Z)",
-        tab="Home",
-        group="Edit",
-        shortcut="Ctrl+Z"
-    )
+
+    @ribbon_action(label="Undo", tooltip="Undo last action (Ctrl+Z)", tab="Home", group="Edit", shortcut="Ctrl+Z")
     def undo(self):
         """Undo last action"""
         if self.project.history.undo():
@@ -25,13 +19,9 @@ class EditOperationsMixin:
         else:
             self.show_status("Nothing to undo", 2000)
             print("Nothing to undo")
-    
+
     @ribbon_action(
-        label="Redo",
-        tooltip="Redo last action (Ctrl+Y or Ctrl+Shift+Z)",
-        tab="Home",
-        group="Edit",
-        shortcut="Ctrl+Y"
+        label="Redo", tooltip="Redo last action (Ctrl+Y or Ctrl+Shift+Z)", tab="Home", group="Edit", shortcut="Ctrl+Y"
     )
     def redo(self):
         """Redo last action"""
@@ -42,117 +32,113 @@ class EditOperationsMixin:
         else:
             self.show_status("Nothing to redo", 2000)
             print("Nothing to redo")
-    
+
     @ribbon_action(
         label="Delete",
         tooltip="Delete selected element (Delete key)",
         tab="Home",
         group="Edit",
         shortcut="Delete",
-        requires_selection=True
+        requires_selection=True,
     )
     def delete_selected_element(self):
         """Delete the currently selected element"""
         if not self.require_selection(min_count=1):
             return
-        
+
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         # Delete the first selected element (for backward compatibility)
         # In the future, we could delete all selected elements
         selected_element = next(iter(self.gl_widget.selected_elements))
-        
+
         try:
-            cmd = DeleteElementCommand(
-                current_page.layout,
-                selected_element,
-                asset_manager=self.project.asset_manager
-            )
+            cmd = DeleteElementCommand(current_page.layout, selected_element, asset_manager=self.project.asset_manager)
             self.project.history.execute(cmd)
-            
+
             # Clear selection
             self.gl_widget.selected_elements.clear()
-            
+
             # Update display
             self.update_view()
-            
+
             self.show_status("Element deleted (Ctrl+Z to undo)", 2000)
             print("Deleted selected element")
-        
+
         except Exception as e:
             self.show_error("Error", f"Failed to delete element: {str(e)}")
             print(f"Error deleting element: {e}")
-    
+
     @ribbon_action(
         label="Rotate Left",
         tooltip="Rotate selected element 90° counter-clockwise",
         tab="Home",
         group="Transform",
-        requires_selection=True
+        requires_selection=True,
     )
     def rotate_left(self):
         """Rotate selected element 90 degrees counter-clockwise"""
         if not self.require_selection(min_count=1):
             return
-        
+
         selected_element = next(iter(self.gl_widget.selected_elements))
         old_rotation = selected_element.rotation
         new_rotation = (old_rotation - 90) % 360
-        
+
         cmd = RotateElementCommand(selected_element, old_rotation, new_rotation)
         self.project.history.execute(cmd)
 
         self.update_view()
         self.show_status(f"Rotated left (Ctrl+Z to undo)", 2000)
         print(f"Rotated element left: {old_rotation}° → {new_rotation}°")
-    
+
     @ribbon_action(
         label="Rotate Right",
         tooltip="Rotate selected element 90° clockwise",
         tab="Home",
         group="Transform",
-        requires_selection=True
+        requires_selection=True,
     )
     def rotate_right(self):
         """Rotate selected element 90 degrees clockwise"""
         if not self.require_selection(min_count=1):
             return
-        
+
         selected_element = next(iter(self.gl_widget.selected_elements))
         old_rotation = selected_element.rotation
         new_rotation = (old_rotation + 90) % 360
-        
+
         cmd = RotateElementCommand(selected_element, old_rotation, new_rotation)
         self.project.history.execute(cmd)
 
         self.update_view()
         self.show_status(f"Rotated right (Ctrl+Z to undo)", 2000)
         print(f"Rotated element right: {old_rotation}° → {new_rotation}°")
-    
+
     @ribbon_action(
         label="Reset Rotation",
         tooltip="Reset selected element rotation to 0°",
         tab="Home",
         group="Transform",
-        requires_selection=True
+        requires_selection=True,
     )
     def reset_rotation(self):
         """Reset selected element rotation to 0 degrees"""
         if not self.require_selection(min_count=1):
             return
-        
+
         selected_element = next(iter(self.gl_widget.selected_elements))
         old_rotation = selected_element.rotation
-        
+
         if old_rotation == 0:
             self.show_status("Element already at 0°", 2000)
             return
-        
+
         cmd = RotateElementCommand(selected_element, old_rotation, 0)
         self.project.history.execute(cmd)
-        
+
         self.update_view()
         self.show_status("Reset rotation to 0° (Ctrl+Z to undo)", 2000)
         print(f"Reset element rotation: {old_rotation}° → 0°")
diff --git a/pyPhotoAlbum/mixins/operations/element_ops.py b/pyPhotoAlbum/mixins/operations/element_ops.py
index f38622e..770a1fb 100644
--- a/pyPhotoAlbum/mixins/operations/element_ops.py
+++ b/pyPhotoAlbum/mixins/operations/element_ops.py
@@ -11,33 +11,26 @@ from pyPhotoAlbum.async_backend import get_image_dimensions
 
 class ElementOperationsMixin:
     """Mixin providing element creation and manipulation operations"""
-    
+
     @ribbon_action(
-        label="Image",
-        tooltip="Add an image to the current page",
-        tab="Insert",
-        group="Media",
-        requires_page=True
+        label="Image", tooltip="Add an image to the current page", tab="Insert", group="Media", requires_page=True
     )
     def add_image(self):
         """Add an image to the current page"""
         if not self.require_page():
             return
-        
+
         file_path, _ = QFileDialog.getOpenFileName(
-            self,
-            "Select Image",
-            "",
-            "Image Files (*.jpg *.jpeg *.png *.gif *.bmp *.tiff *.webp);;All Files (*)"
+            self, "Select Image", "", "Image Files (*.jpg *.jpeg *.png *.gif *.bmp *.tiff *.webp);;All Files (*)"
         )
-        
+
         if not file_path:
             return
-        
+
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         try:
             # Import asset to project
             asset_path = self.project.asset_manager.import_asset(file_path)
@@ -54,111 +47,87 @@ class ElementOperationsMixin:
             # Create image element at center of page
             page_width_mm = current_page.layout.size[0]
             page_height_mm = current_page.layout.size[1]
-            
+
             # Center position
             x = (page_width_mm - img_width) / 2
             y = (page_height_mm - img_height) / 2
-            
-            new_image = ImageData(
-                image_path=asset_path,
-                x=x,
-                y=y,
-                width=img_width,
-                height=img_height
-            )
-            
+
+            new_image = ImageData(image_path=asset_path, x=x, y=y, width=img_width, height=img_height)
+
             # Add element using command pattern for undo/redo
-            cmd = AddElementCommand(
-                current_page.layout,
-                new_image,
-                asset_manager=self.project.asset_manager
-            )
+            cmd = AddElementCommand(current_page.layout, new_image, asset_manager=self.project.asset_manager)
             self.project.history.execute(cmd)
-            
+
             self.update_view()
             self.show_status("Added image (Ctrl+Z to undo)", 2000)
             print(f"Added image to page {self.get_current_page_index() + 1}: {asset_path}")
-            
+
         except Exception as e:
             self.show_error("Error", f"Failed to add image: {str(e)}")
             print(f"Error adding image: {e}")
-    
+
     @ribbon_action(
-        label="Text",
-        tooltip="Add a text box to the current page",
-        tab="Insert",
-        group="Media",
-        requires_page=True
+        label="Text", tooltip="Add a text box to the current page", tab="Insert", group="Media", requires_page=True
     )
     def add_text(self):
         """Add text to the current page"""
         if not self.require_page():
             return
-        
+
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         # Create text box element at center of page
         page_width_mm = current_page.layout.size[0]
         page_height_mm = current_page.layout.size[1]
-        
+
         text_width = 200
         text_height = 50
-        
+
         # Center position
         x = (page_width_mm - text_width) / 2
         y = (page_height_mm - text_height) / 2
-        
-        new_text = TextBoxData(
-            text_content="New Text",
-            x=x,
-            y=y,
-            width=text_width,
-            height=text_height
-        )
-        
+
+        new_text = TextBoxData(text_content="New Text", x=x, y=y, width=text_width, height=text_height)
+
         current_page.layout.add_element(new_text)
         self.update_view()
-        
+
         print(f"Added text box to page {self.get_current_page_index() + 1}")
-    
+
     @ribbon_action(
         label="Placeholder",
         tooltip="Add a placeholder to the current page",
         tab="Insert",
         group="Media",
-        requires_page=True
+        requires_page=True,
     )
     def add_placeholder(self):
         """Add a placeholder to the current page"""
         if not self.require_page():
             return
-        
+
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         # Create placeholder element at center of page
         page_width_mm = current_page.layout.size[0]
         page_height_mm = current_page.layout.size[1]
-        
+
         placeholder_width = 200
         placeholder_height = 150
-        
+
         # Center position
         x = (page_width_mm - placeholder_width) / 2
         y = (page_height_mm - placeholder_height) / 2
-        
+
         new_placeholder = PlaceholderData(
-            placeholder_type="image",
-            x=x,
-            y=y,
-            width=placeholder_width,
-            height=placeholder_height
+            placeholder_type="image", x=x, y=y, width=placeholder_width, height=placeholder_height
         )
-        
+
         current_page.layout.add_element(new_placeholder)
         self.update_view()
-        
+
         print(f"Added placeholder to page {self.get_current_page_index() + 1}")
diff --git a/pyPhotoAlbum/mixins/operations/file_ops.py b/pyPhotoAlbum/mixins/operations/file_ops.py
index 96bfcb8..7918558 100644
--- a/pyPhotoAlbum/mixins/operations/file_ops.py
+++ b/pyPhotoAlbum/mixins/operations/file_ops.py
@@ -5,9 +5,19 @@ File operations mixin for pyPhotoAlbum
 import os
 
 from PyQt6.QtWidgets import (
-    QFileDialog, QDialog, QVBoxLayout, QHBoxLayout, QLabel,
-    QDoubleSpinBox, QSpinBox, QPushButton, QGroupBox, QRadioButton,
-    QButtonGroup, QLineEdit, QTextEdit
+    QFileDialog,
+    QDialog,
+    QVBoxLayout,
+    QHBoxLayout,
+    QLabel,
+    QDoubleSpinBox,
+    QSpinBox,
+    QPushButton,
+    QGroupBox,
+    QRadioButton,
+    QButtonGroup,
+    QLineEdit,
+    QTextEdit,
 )
 from pyPhotoAlbum.decorators import ribbon_action, numerical_input
 from pyPhotoAlbum.project import Project, Page
@@ -21,23 +31,17 @@ from pyPhotoAlbum.asset_heal_dialog import AssetHealDialog
 
 class FileOperationsMixin:
     """Mixin providing file-related operations"""
-    
-    @ribbon_action(
-        label="New",
-        tooltip="Create a new project",
-        tab="Home",
-        group="File",
-        shortcut="Ctrl+N"
-    )
+
+    @ribbon_action(label="New", tooltip="Create a new project", tab="Home", group="File", shortcut="Ctrl+N")
     def new_project(self):
         """Create a new project with initial setup dialog"""
         # Create new project setup dialog
         dialog = QDialog(self)
         dialog.setWindowTitle("New Project Setup")
         dialog.setMinimumWidth(450)
-        
+
         layout = QVBoxLayout()
-        
+
         # Project name group
         name_group = QGroupBox("Project Name")
         name_layout = QVBoxLayout()
@@ -47,16 +51,16 @@ class FileOperationsMixin:
         name_layout.addWidget(name_input)
         name_group.setLayout(name_layout)
         layout.addWidget(name_group)
-        
+
         # Default page size group
         size_group = QGroupBox("Default Page Size")
         size_layout = QVBoxLayout()
-        
+
         info_label = QLabel("This will be the default size for all new pages in this project.")
         info_label.setWordWrap(True)
         info_label.setStyleSheet("font-size: 9pt; color: gray;")
         size_layout.addWidget(info_label)
-        
+
         # Width
         width_layout = QHBoxLayout()
         width_layout.addWidget(QLabel("Width:"))
@@ -66,7 +70,7 @@ class FileOperationsMixin:
         width_spinbox.setSuffix(" mm")
         width_layout.addWidget(width_spinbox)
         size_layout.addLayout(width_layout)
-        
+
         # Height
         height_layout = QHBoxLayout()
         height_layout.addWidget(QLabel("Height:"))
@@ -76,37 +80,37 @@ class FileOperationsMixin:
         height_spinbox.setSuffix(" mm")
         height_layout.addWidget(height_spinbox)
         size_layout.addLayout(height_layout)
-        
+
         # Add common size presets
         presets_layout = QHBoxLayout()
         presets_layout.addWidget(QLabel("Presets:"))
-        
+
         def set_preset(w, h):
             width_spinbox.setValue(w)
             height_spinbox.setValue(h)
-        
+
         preset_a4 = QPushButton("A4 (210×297)")
         preset_a4.clicked.connect(lambda: set_preset(210, 297))
         presets_layout.addWidget(preset_a4)
-        
+
         preset_a5 = QPushButton("A5 (148×210)")
         preset_a5.clicked.connect(lambda: set_preset(148, 210))
         presets_layout.addWidget(preset_a5)
-        
+
         preset_square = QPushButton("Square (200×200)")
         preset_square.clicked.connect(lambda: set_preset(200, 200))
         presets_layout.addWidget(preset_square)
-        
+
         presets_layout.addStretch()
         size_layout.addLayout(presets_layout)
-        
+
         size_group.setLayout(size_layout)
         layout.addWidget(size_group)
-        
+
         # DPI settings group
         dpi_group = QGroupBox("DPI Settings")
         dpi_layout = QVBoxLayout()
-        
+
         # Working DPI
         working_dpi_layout = QHBoxLayout()
         working_dpi_layout.addWidget(QLabel("Working DPI:"))
@@ -115,7 +119,7 @@ class FileOperationsMixin:
         working_dpi_spinbox.setValue(300)
         working_dpi_layout.addWidget(working_dpi_spinbox)
         dpi_layout.addLayout(working_dpi_layout)
-        
+
         # Export DPI
         export_dpi_layout = QHBoxLayout()
         export_dpi_layout.addWidget(QLabel("Export DPI:"))
@@ -124,10 +128,10 @@ class FileOperationsMixin:
         export_dpi_spinbox.setValue(300)
         export_dpi_layout.addWidget(export_dpi_spinbox)
         dpi_layout.addLayout(export_dpi_layout)
-        
+
         dpi_group.setLayout(dpi_layout)
         layout.addWidget(dpi_group)
-        
+
         # Buttons
         button_layout = QHBoxLayout()
         cancel_btn = QPushButton("Cancel")
@@ -135,14 +139,14 @@ class FileOperationsMixin:
         create_btn = QPushButton("Create Project")
         create_btn.clicked.connect(dialog.accept)
         create_btn.setDefault(True)
-        
+
         button_layout.addStretch()
         button_layout.addWidget(cancel_btn)
         button_layout.addWidget(create_btn)
         layout.addLayout(button_layout)
-        
+
         dialog.setLayout(layout)
-        
+
         # Show dialog
         if dialog.exec() == QDialog.DialogCode.Accepted:
             # Get values
@@ -153,7 +157,7 @@ class FileOperationsMixin:
             export_dpi = export_dpi_spinbox.value()
 
             # Cleanup old project if it exists
-            if hasattr(self, 'project') and self.project:
+            if hasattr(self, "project") and self.project:
                 self.project.cleanup()
 
             # Create project with custom settings
@@ -167,34 +171,25 @@ class FileOperationsMixin:
 
             # Update view
             self.update_view()
-            
+
             self.show_status(f"New project created: {project_name} ({width_mm}×{height_mm} mm)")
             print(f"New project created: {project_name}, default page size: {width_mm}×{height_mm} mm")
         else:
             # User cancelled - keep current project
             print("New project creation cancelled")
-    
-    @ribbon_action(
-        label="Open",
-        tooltip="Open an existing project",
-        tab="Home",
-        group="File",
-        shortcut="Ctrl+O"
-    )
+
+    @ribbon_action(label="Open", tooltip="Open an existing project", tab="Home", group="File", shortcut="Ctrl+O")
     def open_project(self):
         """Open an existing project with async loading and progress bar"""
         file_path, _ = QFileDialog.getOpenFileName(
-            self,
-            "Open Project",
-            "",
-            "pyPhotoAlbum Projects (*.ppz);;All Files (*)"
+            self, "Open Project", "", "pyPhotoAlbum Projects (*.ppz);;All Files (*)"
         )
 
         if file_path:
             print(f"Opening project: {file_path}")
 
             # Create loading widget if not exists
-            if not hasattr(self, '_loading_widget'):
+            if not hasattr(self, "_loading_widget"):
                 self._loading_widget = LoadingWidget(self)
 
             # Show loading widget
@@ -214,29 +209,29 @@ class FileOperationsMixin:
 
     def _on_load_progress(self, current: int, total: int, message: str):
         """Handle loading progress updates"""
-        if hasattr(self, '_loading_widget'):
+        if hasattr(self, "_loading_widget"):
             self._loading_widget.set_progress(current, total)
             self._loading_widget.set_status(message)
 
     def _on_load_complete(self, project):
         """Handle successful project load"""
         # Cleanup old project if it exists
-        if hasattr(self, 'project') and self.project:
+        if hasattr(self, "project") and self.project:
             self.project.cleanup()
 
         # Set new project
         self.project = project
 
         # Set file path and mark as clean
-        if hasattr(self, '_opening_file_path'):
+        if hasattr(self, "_opening_file_path"):
             self.project.file_path = self._opening_file_path
-            delattr(self, '_opening_file_path')
+            delattr(self, "_opening_file_path")
         self.project.mark_clean()
 
         self.gl_widget.current_page_index = 0  # Reset to first page
 
         # Hide loading widget
-        if hasattr(self, '_loading_widget'):
+        if hasattr(self, "_loading_widget"):
             self._loading_widget.hide_loading()
 
         # Update view (this will trigger progressive image loading)
@@ -254,32 +249,23 @@ class FileOperationsMixin:
     def _on_load_failed(self, error_msg: str):
         """Handle project load failure"""
         # Hide loading widget
-        if hasattr(self, '_loading_widget'):
+        if hasattr(self, "_loading_widget"):
             self._loading_widget.hide_loading()
 
         error_msg = f"Failed to open project: {error_msg}"
         self.show_status(error_msg)
         self.show_error("Load Failed", error_msg)
         print(error_msg)
-    
-    @ribbon_action(
-        label="Save",
-        tooltip="Save the current project",
-        tab="Home",
-        group="File",
-        shortcut="Ctrl+S"
-    )
+
+    @ribbon_action(label="Save", tooltip="Save the current project", tab="Home", group="File", shortcut="Ctrl+S")
     def save_project(self):
         """Save the current project"""
         # If project has a file path, use it; otherwise prompt for location
-        file_path = self.project.file_path if hasattr(self.project, 'file_path') and self.project.file_path else None
+        file_path = self.project.file_path if hasattr(self.project, "file_path") and self.project.file_path else None
 
         if not file_path:
             file_path, _ = QFileDialog.getSaveFileName(
-                self,
-                "Save Project",
-                "",
-                "pyPhotoAlbum Projects (*.ppz);;All Files (*)"
+                self, "Save Project", "", "pyPhotoAlbum Projects (*.ppz);;All Files (*)"
             )
 
         if file_path:
@@ -298,12 +284,7 @@ class FileOperationsMixin:
                 self.show_status(error_msg)
                 print(error_msg)
 
-    @ribbon_action(
-        label="Heal Assets",
-        tooltip="Reconnect missing image assets",
-        tab="Home",
-        group="File"
-    )
+    @ribbon_action(label="Heal Assets", tooltip="Reconnect missing image assets", tab="Home", group="File")
     def heal_assets(self):
         """Open the asset healing dialog to reconnect missing images"""
         dialog = AssetHealDialog(self.project, self)
@@ -348,10 +329,12 @@ class FileOperationsMixin:
         msg.setWindowTitle("Missing Assets")
         msg.setText(f"{len(missing_assets)} image(s) could not be found in the assets folder:")
         msg.setInformativeText(asset_list)
-        msg.setDetailedText("These images need to be reconnected using the 'Heal Assets' feature.\n\n"
-                           "Go to: Home → Heal Assets\n\n"
-                           "Add search paths where the original images might be located, "
-                           "then click 'Attempt Healing' to find and import them.")
+        msg.setDetailedText(
+            "These images need to be reconnected using the 'Heal Assets' feature.\n\n"
+            "Go to: Home → Heal Assets\n\n"
+            "Add search paths where the original images might be located, "
+            "then click 'Attempt Healing' to find and import them."
+        )
         msg.setStandardButtons(QMessageBox.StandardButton.Ok | QMessageBox.StandardButton.Open)
         msg.button(QMessageBox.StandardButton.Open).setText("Open Heal Assets")
 
@@ -360,30 +343,22 @@ class FileOperationsMixin:
             self.heal_assets()
 
     @ribbon_action(
-        label="Project Settings",
-        tooltip="Configure project-wide page size and defaults",
-        tab="Home",
-        group="File"
-    )
-    @numerical_input(
-        fields=[
-            ('width', 'Width', 'mm', 10, 1000),
-            ('height', 'Height', 'mm', 10, 1000)
-        ]
+        label="Project Settings", tooltip="Configure project-wide page size and defaults", tab="Home", group="File"
     )
+    @numerical_input(fields=[("width", "Width", "mm", 10, 1000), ("height", "Height", "mm", 10, 1000)])
     def project_settings(self):
         """Configure project-wide settings including default page size"""
         # Create dialog
         dialog = QDialog(self)
         dialog.setWindowTitle("Project Settings")
         dialog.setMinimumWidth(500)
-        
+
         layout = QVBoxLayout()
-        
+
         # Page size group
         size_group = QGroupBox("Default Page Size")
         size_layout = QVBoxLayout()
-        
+
         # Width
         width_layout = QHBoxLayout()
         width_layout.addWidget(QLabel("Width:"))
@@ -393,7 +368,7 @@ class FileOperationsMixin:
         width_spinbox.setSuffix(" mm")
         width_layout.addWidget(width_spinbox)
         size_layout.addLayout(width_layout)
-        
+
         # Height
         height_layout = QHBoxLayout()
         height_layout.addWidget(QLabel("Height:"))
@@ -403,14 +378,14 @@ class FileOperationsMixin:
         height_spinbox.setSuffix(" mm")
         height_layout.addWidget(height_spinbox)
         size_layout.addLayout(height_layout)
-        
+
         size_group.setLayout(size_layout)
         layout.addWidget(size_group)
-        
+
         # DPI settings group
         dpi_group = QGroupBox("DPI Settings")
         dpi_layout = QVBoxLayout()
-        
+
         # Working DPI
         working_dpi_layout = QHBoxLayout()
         working_dpi_layout.addWidget(QLabel("Working DPI:"))
@@ -419,7 +394,7 @@ class FileOperationsMixin:
         working_dpi_spinbox.setValue(self.project.working_dpi)
         working_dpi_layout.addWidget(working_dpi_spinbox)
         dpi_layout.addLayout(working_dpi_layout)
-        
+
         # Export DPI
         export_dpi_layout = QHBoxLayout()
         export_dpi_layout.addWidget(QLabel("Export DPI:"))
@@ -428,48 +403,50 @@ class FileOperationsMixin:
         export_dpi_spinbox.setValue(self.project.export_dpi)
         export_dpi_layout.addWidget(export_dpi_spinbox)
         dpi_layout.addLayout(export_dpi_layout)
-        
+
         dpi_group.setLayout(dpi_layout)
         layout.addWidget(dpi_group)
-        
+
         # Content scaling options (only if pages exist and size is changing)
         scaling_group = None
         scaling_buttons = None
-        
+
         if self.project.pages:
             scaling_group = QGroupBox("Apply to Existing Pages")
             scaling_layout = QVBoxLayout()
-            
-            info_label = QLabel("How should existing content be adjusted?\n(Pages with manual sizing will not be affected)")
+
+            info_label = QLabel(
+                "How should existing content be adjusted?\n(Pages with manual sizing will not be affected)"
+            )
             info_label.setWordWrap(True)
             scaling_layout.addWidget(info_label)
-            
+
             scaling_buttons = QButtonGroup()
-            
+
             proportional_radio = QRadioButton("Resize proportionally (fit to smallest axis)")
             proportional_radio.setToolTip("Scale content uniformly to fit the new page size")
             scaling_buttons.addButton(proportional_radio, 0)
             scaling_layout.addWidget(proportional_radio)
-            
+
             stretch_radio = QRadioButton("Resize on both axes (stretch)")
             stretch_radio.setToolTip("Scale width and height independently")
             scaling_buttons.addButton(stretch_radio, 1)
             scaling_layout.addWidget(stretch_radio)
-            
+
             reposition_radio = QRadioButton("Keep content size, reposition to center")
             reposition_radio.setToolTip("Maintain element sizes but center them on new page")
             scaling_buttons.addButton(reposition_radio, 2)
             scaling_layout.addWidget(reposition_radio)
-            
+
             none_radio = QRadioButton("Don't adjust content (page size only)")
             none_radio.setToolTip("Only change page size, leave content as-is")
             none_radio.setChecked(True)  # Default
             scaling_buttons.addButton(none_radio, 3)
             scaling_layout.addWidget(none_radio)
-            
+
             scaling_group.setLayout(scaling_layout)
             layout.addWidget(scaling_group)
-        
+
         # Buttons
         button_layout = QHBoxLayout()
         cancel_btn = QPushButton("Cancel")
@@ -477,14 +454,14 @@ class FileOperationsMixin:
         ok_btn = QPushButton("OK")
         ok_btn.clicked.connect(dialog.accept)
         ok_btn.setDefault(True)
-        
+
         button_layout.addStretch()
         button_layout.addWidget(cancel_btn)
         button_layout.addWidget(ok_btn)
         layout.addLayout(button_layout)
-        
+
         dialog.setLayout(layout)
-        
+
         # Show dialog
         if dialog.exec() == QDialog.DialogCode.Accepted:
             # Get new values
@@ -492,32 +469,32 @@ class FileOperationsMixin:
             new_height = height_spinbox.value()
             new_working_dpi = working_dpi_spinbox.value()
             new_export_dpi = export_dpi_spinbox.value()
-            
+
             # Determine scaling mode
-            scaling_mode = 'none'
+            scaling_mode = "none"
             if scaling_buttons:
                 selected_id = scaling_buttons.checkedId()
-                modes = {0: 'proportional', 1: 'stretch', 2: 'reposition', 3: 'none'}
-                scaling_mode = modes.get(selected_id, 'none')
-            
+                modes = {0: "proportional", 1: "stretch", 2: "reposition", 3: "none"}
+                scaling_mode = modes.get(selected_id, "none")
+
             # Apply settings
             old_size = self.project.page_size_mm
             self.project.page_size_mm = (new_width, new_height)
             self.project.working_dpi = new_working_dpi
             self.project.export_dpi = new_export_dpi
-            
+
             # Update existing pages (exclude manually sized ones)
             if self.project.pages and old_size != (new_width, new_height):
                 self._apply_page_size_to_project(old_size, (new_width, new_height), scaling_mode)
-            
+
             self.update_view()
             self.show_status(f"Project settings updated: {new_width}×{new_height} mm", 2000)
             print(f"Project settings updated: {new_width}×{new_height} mm, scaling mode: {scaling_mode}")
-    
+
     def _apply_page_size_to_project(self, old_size, new_size, scaling_mode):
         """
         Apply new page size to all non-manually-sized pages
-        
+
         Args:
             old_size: Old page size (width, height) in mm
             new_size: New page size (width, height) in mm
@@ -525,41 +502,41 @@ class FileOperationsMixin:
         """
         old_width, old_height = old_size
         new_width, new_height = new_size
-        
+
         width_ratio = new_width / old_width if old_width > 0 else 1.0
         height_ratio = new_height / old_height if old_height > 0 else 1.0
-        
+
         for page in self.project.pages:
             # Skip manually sized pages
             if page.manually_sized:
                 continue
-            
+
             # Update page size
             old_page_width, old_page_height = page.layout.size
-            
+
             # For double spreads, maintain the 2x multiplier
             if page.is_double_spread:
                 page.layout.size = (new_width * 2, new_height)
             else:
                 page.layout.size = (new_width, new_height)
-            
+
             # Apply content scaling based on mode
-            if scaling_mode == 'proportional':
+            if scaling_mode == "proportional":
                 # Use smallest ratio to fit content
                 scale = min(width_ratio, height_ratio)
                 self._scale_page_elements(page, scale, scale)
-            elif scaling_mode == 'stretch':
+            elif scaling_mode == "stretch":
                 # Scale independently on each axis
                 self._scale_page_elements(page, width_ratio, height_ratio)
-            elif scaling_mode == 'reposition':
+            elif scaling_mode == "reposition":
                 # Keep size, center content
                 self._reposition_page_elements(page, old_size, new_size)
             # 'none' - do nothing to elements
-    
+
     def _scale_page_elements(self, page, x_scale, y_scale):
         """
         Scale all elements on a page
-        
+
         Args:
             page: Page object
             x_scale: Horizontal scale factor
@@ -569,15 +546,15 @@ class FileOperationsMixin:
             # Scale position
             x, y = element.position
             element.position = (x * x_scale, y * y_scale)
-            
+
             # Scale size
             width, height = element.size
             element.size = (width * x_scale, height * y_scale)
-    
+
     def _reposition_page_elements(self, page, old_size, new_size):
         """
         Reposition elements to center them on the new page size
-        
+
         Args:
             page: Page object
             old_size: Old page size (width, height) in mm
@@ -585,20 +562,15 @@ class FileOperationsMixin:
         """
         old_width, old_height = old_size
         new_width, new_height = new_size
-        
+
         x_offset = (new_width - old_width) / 2.0
         y_offset = (new_height - old_height) / 2.0
-        
+
         for element in page.layout.elements:
             x, y = element.position
             element.position = (x + x_offset, y + y_offset)
-    
-    @ribbon_action(
-        label="Export PDF",
-        tooltip="Export project to PDF",
-        tab="Export",
-        group="Export"
-    )
+
+    @ribbon_action(label="Export PDF", tooltip="Export project to PDF", tab="Export", group="Export")
     def export_pdf(self):
         """Export project to PDF using async backend (non-blocking)"""
         # Check if we have pages to export
@@ -607,19 +579,14 @@ class FileOperationsMixin:
             return
 
         # Show file save dialog
-        file_path, _ = QFileDialog.getSaveFileName(
-            self,
-            "Export to PDF",
-            "",
-            "PDF Files (*.pdf);;All Files (*)"
-        )
+        file_path, _ = QFileDialog.getSaveFileName(self, "Export to PDF", "", "PDF Files (*.pdf);;All Files (*)")
 
         if not file_path:
             return
 
         # Ensure .pdf extension
-        if not file_path.lower().endswith('.pdf'):
-            file_path += '.pdf'
+        if not file_path.lower().endswith(".pdf"):
+            file_path += ".pdf"
 
         # Use async PDF export (non-blocking, UI stays responsive)
         success = self.gl_widget.export_pdf_async(self.project, file_path, export_dpi=300)
@@ -628,12 +595,7 @@ class FileOperationsMixin:
         else:
             self.show_status("PDF export failed to start", 3000)
 
-    @ribbon_action(
-        label="About",
-        tooltip="About pyPhotoAlbum and data format version",
-        tab="Home",
-        group="File"
-    )
+    @ribbon_action(label="About", tooltip="About pyPhotoAlbum and data format version", tab="Home", group="File")
     def show_about(self):
         """Show about dialog with version information"""
         dialog = QDialog(self)
diff --git a/pyPhotoAlbum/mixins/operations/merge_ops.py b/pyPhotoAlbum/mixins/operations/merge_ops.py
index 1b44faf..5029b59 100644
--- a/pyPhotoAlbum/mixins/operations/merge_ops.py
+++ b/pyPhotoAlbum/mixins/operations/merge_ops.py
@@ -20,7 +20,7 @@ class MergeOperationsMixin:
         label="Merge Projects",
         tooltip="Merge another project file with the current project",
         tab="File",
-        group="Import/Export"
+        group="Import/Export",
     )
     def merge_projects(self):
         """
@@ -35,22 +35,19 @@ class MergeOperationsMixin:
                 self,
                 "Unsaved Changes",
                 "You have unsaved changes in the current project. Save before merging?",
-                QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No | QMessageBox.StandardButton.Cancel
+                QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No | QMessageBox.StandardButton.Cancel,
             )
 
             if reply == QMessageBox.StandardButton.Cancel:
                 return
             elif reply == QMessageBox.StandardButton.Yes:
                 # Save current project first
-                if hasattr(self, 'save_project'):
+                if hasattr(self, "save_project"):
                     self.save_project()
 
         # Select file to merge
         file_path, _ = QFileDialog.getOpenFileName(
-            self,
-            "Select Project to Merge",
-            "",
-            "Photo Album Projects (*.ppz);;All Files (*)"
+            self, "Select Project to Merge", "", "Photo Album Projects (*.ppz);;All Files (*)"
         )
 
         if not file_path:
@@ -58,7 +55,7 @@ class MergeOperationsMixin:
 
         try:
             # Disable autosave during merge
-            if hasattr(self, '_autosave_timer'):
+            if hasattr(self, "_autosave_timer"):
                 self._autosave_timer.stop()
 
             # Load the other project
@@ -82,14 +79,10 @@ class MergeOperationsMixin:
                     self._perform_concatenation(our_data, their_data)
 
         except Exception as e:
-            QMessageBox.critical(
-                self,
-                "Merge Error",
-                f"Failed to merge projects:\n{str(e)}"
-            )
+            QMessageBox.critical(self, "Merge Error", f"Failed to merge projects:\n{str(e)}")
         finally:
             # Re-enable autosave
-            if hasattr(self, '_autosave_timer'):
+            if hasattr(self, "_autosave_timer"):
                 self._autosave_timer.start()
 
     def _perform_merge_with_conflicts(self, our_data, their_data):
@@ -104,7 +97,7 @@ class MergeOperationsMixin:
                 self,
                 "No Conflicts",
                 "No conflicts detected. Merge projects automatically?",
-                QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No
+                QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
             )
 
             if reply != QMessageBox.StandardButton.Yes:
@@ -117,11 +110,7 @@ class MergeOperationsMixin:
             dialog = MergeDialog(our_data, their_data, self)
 
             if dialog.exec() != QMessageBox.DialogCode.Accepted:
-                QMessageBox.information(
-                    self,
-                    "Merge Cancelled",
-                    "Merge operation cancelled."
-                )
+                QMessageBox.information(self, "Merge Cancelled", "Merge operation cancelled.")
                 return
 
             # Get merged data from dialog
@@ -135,7 +124,7 @@ class MergeOperationsMixin:
             "Merge Complete",
             f"Projects merged successfully.\n"
             f"Total pages: {len(merged_data.get('pages', []))}\n"
-            f"Resolved conflicts: {len(conflicts)}"
+            f"Resolved conflicts: {len(conflicts)}",
         )
 
     def _perform_concatenation(self, our_data, their_data):
@@ -147,7 +136,7 @@ class MergeOperationsMixin:
             f"  • {our_data.get('name', 'Untitled')}\n"
             f"  • {their_data.get('name', 'Untitled')}\n\n"
             f"Concatenate them (combine all pages)?",
-            QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No
+            QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
         )
 
         if reply != QMessageBox.StandardButton.Yes:
@@ -162,8 +151,7 @@ class MergeOperationsMixin:
         QMessageBox.information(
             self,
             "Concatenation Complete",
-            f"Projects concatenated successfully.\n"
-            f"Total pages: {len(merged_data.get('pages', []))}"
+            f"Projects concatenated successfully.\n" f"Total pages: {len(merged_data.get('pages', []))}",
         )
 
     def _apply_merged_data(self, merged_data):
@@ -182,9 +170,9 @@ class MergeOperationsMixin:
         new_project.mark_dirty()
 
         # Update UI
-        if hasattr(self, 'gl_widget'):
+        if hasattr(self, "gl_widget"):
             self.gl_widget.set_project(new_project)
             self.gl_widget.update()
 
-        if hasattr(self, 'status_bar'):
+        if hasattr(self, "status_bar"):
             self.status_bar.showMessage("Merge completed successfully", 3000)
diff --git a/pyPhotoAlbum/mixins/operations/page_ops.py b/pyPhotoAlbum/mixins/operations/page_ops.py
index 9c22bfb..be0ad97 100644
--- a/pyPhotoAlbum/mixins/operations/page_ops.py
+++ b/pyPhotoAlbum/mixins/operations/page_ops.py
@@ -10,16 +10,11 @@ from pyPhotoAlbum.page_layout import PageLayout
 
 class PageOperationsMixin:
     """Mixin providing page management operations"""
-    
+
     # Note: Previous/Next page navigation removed - now using scrollable multi-page view
     # User can scroll through all pages vertically
-    
-    @ribbon_action(
-        label="Add Page",
-        tooltip="Add a new page to the project",
-        tab="Layout",
-        group="Page"
-    )
+
+    @ribbon_action(label="Add Page", tooltip="Add a new page to the project", tab="Layout", group="Page")
     def add_page(self):
         """Add a new page to the project after the current page"""
         # Get the most visible page in viewport to determine insertion point
@@ -72,13 +67,8 @@ class PageOperationsMixin:
         # Get display name for status message
         new_page_name = self.project.get_page_display_name(new_page)
         print(f"Added {new_page_name} at position {insert_index + 1} with size {width_mm}×{height_mm} mm")
-    
-    @ribbon_action(
-        label="Page Setup",
-        tooltip="Configure page size and settings",
-        tab="Layout",
-        group="Page"
-    )
+
+    @ribbon_action(label="Page Setup", tooltip="Configure page size and settings", tab="Layout", group="Page")
     @dialog_action(dialog_class=PageSetupDialog, requires_pages=True)
     def page_setup(self, values):
         """
@@ -90,17 +80,17 @@ class PageOperationsMixin:
         Args:
             values: Dictionary of values from the dialog
         """
-        selected_page = values['selected_page']
-        selected_index = values['selected_index']
+        selected_page = values["selected_page"]
+        selected_index = values["selected_index"]
 
         # Update project cover settings
-        self.project.paper_thickness_mm = values['paper_thickness_mm']
-        self.project.cover_bleed_mm = values['cover_bleed_mm']
+        self.project.paper_thickness_mm = values["paper_thickness_mm"]
+        self.project.cover_bleed_mm = values["cover_bleed_mm"]
 
         # Handle cover designation (only for first page)
         if selected_index == 0:
             was_cover = selected_page.is_cover
-            is_cover = values['is_cover']
+            is_cover = values["is_cover"]
 
             if was_cover != is_cover:
                 selected_page.is_cover = is_cover
@@ -116,8 +106,8 @@ class PageOperationsMixin:
                     print(f"Cover removed from page 1")
 
         # Get new values
-        width_mm = values['width_mm']
-        height_mm = values['height_mm']
+        width_mm = values["width_mm"]
+        height_mm = values["height_mm"]
 
         # Don't allow manual size changes for covers
         if not selected_page.is_cover:
@@ -126,11 +116,11 @@ class PageOperationsMixin:
             if selected_page.is_double_spread:
                 old_base_width = (
                     selected_page.layout.base_width
-                    if hasattr(selected_page.layout, 'base_width')
+                    if hasattr(selected_page.layout, "base_width")
                     else selected_page.layout.size[0] / 2
                 )
                 old_height = selected_page.layout.size[1]
-                size_changed = (old_base_width != width_mm or old_height != height_mm)
+                size_changed = old_base_width != width_mm or old_height != height_mm
 
                 if size_changed:
                     # Update double spread
@@ -143,7 +133,7 @@ class PageOperationsMixin:
                     )
             else:
                 old_size = selected_page.layout.size
-                size_changed = (old_size != (width_mm, height_mm))
+                size_changed = old_size != (width_mm, height_mm)
 
                 if size_changed:
                     # Update single page
@@ -151,16 +141,15 @@ class PageOperationsMixin:
                     selected_page.layout.base_width = width_mm
                     selected_page.manually_sized = True
                     print(
-                        f"{self.project.get_page_display_name(selected_page)} "
-                        f"updated to {width_mm}×{height_mm} mm"
+                        f"{self.project.get_page_display_name(selected_page)} " f"updated to {width_mm}×{height_mm} mm"
                     )
 
         # Update DPI settings
-        self.project.working_dpi = values['working_dpi']
-        self.project.export_dpi = values['export_dpi']
+        self.project.working_dpi = values["working_dpi"]
+        self.project.export_dpi = values["export_dpi"]
 
         # Set as default if checkbox is checked
-        if values['set_as_default']:
+        if values["set_as_default"]:
             self.project.page_size_mm = (width_mm, height_mm)
             print(f"Project default page size set to {width_mm}×{height_mm} mm")
 
@@ -172,15 +161,12 @@ class PageOperationsMixin:
             status_msg = f"{page_name} updated"
         else:
             status_msg = f"{page_name} size: {width_mm}×{height_mm} mm"
-            if values['set_as_default']:
+            if values["set_as_default"]:
                 status_msg += " (set as default)"
         self.show_status(status_msg, 2000)
 
     @ribbon_action(
-        label="Toggle Spread",
-        tooltip="Toggle double page spread for current page",
-        tab="Layout",
-        group="Page"
+        label="Toggle Spread", tooltip="Toggle double page spread for current page", tab="Layout", group="Page"
     )
     def toggle_double_spread(self):
         """Toggle double spread for the current page"""
@@ -195,31 +181,31 @@ class PageOperationsMixin:
             page_index = 0
 
         current_page = self.project.pages[page_index]
-        
+
         # Toggle the state
         is_double = not current_page.is_double_spread
         current_page.is_double_spread = is_double
-        
+
         # Mark as manually sized when toggling spread
         current_page.manually_sized = True
-        
+
         # Update the page layout width
         current_width = current_page.layout.size[0]
         current_height = current_page.layout.size[1]
-        
+
         # Get base width (might already be doubled)
-        if hasattr(current_page.layout, 'base_width'):
+        if hasattr(current_page.layout, "base_width"):
             base_width = current_page.layout.base_width
         else:
             # Assume current width is single if not marked as facing
             base_width = current_width / 2 if current_page.layout.is_facing_page else current_width
-        
+
         # Set new width based on double spread state
         new_width = base_width * 2 if is_double else base_width
         current_page.layout.base_width = base_width
         current_page.layout.is_facing_page = is_double
         current_page.layout.size = (new_width, current_height)
-        
+
         # Update display
         self.update_view()
 
@@ -227,13 +213,8 @@ class PageOperationsMixin:
         page_name = self.project.get_page_display_name(current_page)
         self.show_status(f"{page_name}: Double spread {status}, width = {new_width:.0f}mm", 2000)
         print(f"{page_name}: Double spread {status}, width = {new_width}mm")
-    
-    @ribbon_action(
-        label="Remove Page",
-        tooltip="Remove the currently selected page",
-        tab="Layout",
-        group="Page"
-    )
+
+    @ribbon_action(label="Remove Page", tooltip="Remove the currently selected page", tab="Layout", group="Page")
     def remove_page(self):
         """Remove the currently selected page"""
         if len(self.project.pages) <= 1:
diff --git a/pyPhotoAlbum/mixins/operations/size_ops.py b/pyPhotoAlbum/mixins/operations/size_ops.py
index 7c48cc5..39bf4e6 100644
--- a/pyPhotoAlbum/mixins/operations/size_ops.py
+++ b/pyPhotoAlbum/mixins/operations/size_ops.py
@@ -9,60 +9,60 @@ from pyPhotoAlbum.commands import ResizeElementsCommand
 
 class SizeOperationsMixin:
     """Mixin providing element sizing operations"""
-    
+
     def _get_selected_elements_list(self):
         """Get list of selected elements for size operations"""
         return list(self.gl_widget.selected_elements) if self.gl_widget.selected_elements else []
-    
+
     @ribbon_action(
         label="Same Size",
         tooltip="Make all selected elements the same size",
         tab="Arrange",
         group="Size",
         requires_selection=True,
-        min_selection=2
+        min_selection=2,
     )
     def make_same_size(self):
         """Make all selected elements the same size"""
         elements = self._get_selected_elements_list()
         if not self.require_selection(min_count=2):
             return
-        
+
         changes = AlignmentManager.make_same_size(elements)
         if changes:
             cmd = ResizeElementsCommand(changes)
             self.project.history.execute(cmd)
             self.update_view()
             self.show_status(f"Resized {len(elements)} elements to same size", 2000)
-    
+
     @ribbon_action(
         label="Same Width",
         tooltip="Make all selected elements the same width",
         tab="Arrange",
         group="Size",
         requires_selection=True,
-        min_selection=2
+        min_selection=2,
     )
     def make_same_width(self):
         """Make all selected elements the same width"""
         elements = self._get_selected_elements_list()
         if not self.require_selection(min_count=2):
             return
-        
+
         changes = AlignmentManager.make_same_width(elements)
         if changes:
             cmd = ResizeElementsCommand(changes)
             self.project.history.execute(cmd)
             self.update_view()
             self.show_status(f"Resized {len(elements)} elements to same width", 2000)
-    
+
     @ribbon_action(
         label="Same Height",
         tooltip="Make all selected elements the same height",
         tab="Arrange",
         group="Size",
         requires_selection=True,
-        min_selection=2
+        min_selection=2,
     )
     def make_same_height(self):
         """Make all selected elements the same height"""
@@ -83,7 +83,7 @@ class SizeOperationsMixin:
         tab="Arrange",
         group="Size",
         requires_selection=True,
-        min_selection=1
+        min_selection=1,
     )
     def fit_to_width(self):
         """Fit selected element to page width"""
@@ -114,7 +114,7 @@ class SizeOperationsMixin:
         tab="Arrange",
         group="Size",
         requires_selection=True,
-        min_selection=1
+        min_selection=1,
     )
     def fit_to_height(self):
         """Fit selected element to page height"""
@@ -145,7 +145,7 @@ class SizeOperationsMixin:
         tab="Arrange",
         group="Size",
         requires_selection=True,
-        min_selection=1
+        min_selection=1,
     )
     def fit_to_page(self):
         """Fit selected element to page dimensions"""
@@ -176,7 +176,7 @@ class SizeOperationsMixin:
         tab="Arrange",
         group="Size",
         requires_selection=True,
-        min_selection=1
+        min_selection=1,
     )
     def expand_image(self):
         """Expand selected image to fill available space"""
@@ -195,16 +195,11 @@ class SizeOperationsMixin:
         other_elements = [e for e in page.layout.elements if e is not element]
 
         # Use configurable min_gap (grid spacing from snapping system, default 10mm)
-        min_gap = getattr(page.layout.snapping_system, 'grid_spacing', 10.0)
+        min_gap = getattr(page.layout.snapping_system, "grid_spacing", 10.0)
 
         # Expand to bounds
         page_width, page_height = page.layout.size
-        change = AlignmentManager.expand_to_bounds(
-            element,
-            (page_width, page_height),
-            other_elements,
-            min_gap
-        )
+        change = AlignmentManager.expand_to_bounds(element, (page_width, page_height), other_elements, min_gap)
 
         if change:
             cmd = ResizeElementsCommand([change])
diff --git a/pyPhotoAlbum/mixins/operations/template_ops.py b/pyPhotoAlbum/mixins/operations/template_ops.py
index 4e9bc54..e7e38f6 100644
--- a/pyPhotoAlbum/mixins/operations/template_ops.py
+++ b/pyPhotoAlbum/mixins/operations/template_ops.py
@@ -3,82 +3,75 @@ Template operations mixin for pyPhotoAlbum
 """
 
 from PyQt6.QtWidgets import (
-    QInputDialog, QDialog, QVBoxLayout, QLabel, QComboBox,
-    QRadioButton, QButtonGroup, QPushButton, QHBoxLayout,
-    QDoubleSpinBox
+    QInputDialog,
+    QDialog,
+    QVBoxLayout,
+    QLabel,
+    QComboBox,
+    QRadioButton,
+    QButtonGroup,
+    QPushButton,
+    QHBoxLayout,
+    QDoubleSpinBox,
 )
 from pyPhotoAlbum.decorators import ribbon_action, undoable_operation
 
 
 class TemplateOperationsMixin:
     """Mixin providing template-related operations"""
-    
+
     @ribbon_action(
         label="Save as Template",
         tooltip="Save current page as a reusable template",
         tab="Layout",
         group="Templates",
-        requires_page=True
+        requires_page=True,
     )
     def save_page_as_template(self):
         """Save current page as a template"""
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         # Check if page has any elements
         if not current_page.layout.elements:
             self.show_warning("Empty Page", "Cannot save an empty page as a template.")
             return
-        
+
         # Ask for template name
         name, ok = QInputDialog.getText(
             self,
             "Save Template",
             "Enter template name:",
-            text=f"Template_{len(self.template_manager.list_templates()) + 1}"
+            text=f"Template_{len(self.template_manager.list_templates()) + 1}",
         )
-        
+
         if not ok or not name:
             return
-        
+
         # Ask for optional description
-        description, ok = QInputDialog.getText(
-            self,
-            "Template Description",
-            "Enter description (optional):"
-        )
-        
+        description, ok = QInputDialog.getText(self, "Template Description", "Enter description (optional):")
+
         if not ok:
             description = ""
-        
+
         try:
             # Create template from page
-            template = self.template_manager.create_template_from_page(
-                current_page,
-                name,
-                description
-            )
-            
+            template = self.template_manager.create_template_from_page(current_page, name, description)
+
             # Save template
             self.template_manager.save_template(template)
-            
-            self.show_info(
-                "Template Saved",
-                f"Template '{name}' has been saved successfully."
-            )
-            
+
+            self.show_info("Template Saved", f"Template '{name}' has been saved successfully.")
+
             print(f"Saved template: {name}")
-        
+
         except Exception as e:
             self.show_error("Error", f"Failed to save template: {str(e)}")
             print(f"Error saving template: {e}")
-    
+
     @ribbon_action(
-        label="New from Template",
-        tooltip="Create a new page from a template",
-        tab="Layout",
-        group="Templates"
+        label="New from Template", tooltip="Create a new page from a template", tab="Layout", group="Templates"
     )
     def new_page_from_template(self):
         """Create a new page from a template"""
@@ -87,8 +80,7 @@ class TemplateOperationsMixin:
 
         if not templates:
             self.show_info(
-                "No Templates",
-                "No templates available. Create a template first by using 'Save as Template'."
+                "No Templates", "No templates available. Create a template first by using 'Save as Template'."
             )
             return
 
@@ -178,7 +170,7 @@ class TemplateOperationsMixin:
                 page_number=new_page_number,
                 target_size_mm=self.project.page_size_mm,
                 scale_mode=scale_mode,
-                margin_percent=margin_percent
+                margin_percent=margin_percent,
             )
 
             # Add to project
@@ -194,63 +186,62 @@ class TemplateOperationsMixin:
         except Exception as e:
             self.show_error("Error", f"Failed to create page from template: {str(e)}")
             print(f"Error creating page from template: {e}")
-    
+
     @ribbon_action(
         label="Apply Template",
         tooltip="Apply a template layout to current page",
         tab="Layout",
         group="Templates",
-        requires_page=True
+        requires_page=True,
     )
-    @undoable_operation(capture='page_elements', description='Apply Template')
+    @undoable_operation(capture="page_elements", description="Apply Template")
     def apply_template_to_page(self):
         """Apply a template to the current page"""
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         # Get available templates
         templates = self.template_manager.list_templates()
-        
+
         if not templates:
             self.show_info(
-                "No Templates",
-                "No templates available. Create a template first by using 'Save as Template'."
+                "No Templates", "No templates available. Create a template first by using 'Save as Template'."
             )
             return
-        
+
         # Create dialog for template application options
         dialog = QDialog(self)
         dialog.setWindowTitle("Apply Template")
         dialog.setMinimumWidth(400)
-        
+
         layout = QVBoxLayout()
-        
+
         # Template selection
         layout.addWidget(QLabel("Select Template:"))
         template_combo = QComboBox()
         template_combo.addItems(templates)
         layout.addWidget(template_combo)
-        
+
         layout.addSpacing(10)
-        
+
         # Mode selection
         layout.addWidget(QLabel("Mode:"))
         mode_group = QButtonGroup(dialog)
-        
+
         replace_radio = QRadioButton("Replace with placeholders")
         replace_radio.setChecked(True)
         replace_radio.setToolTip("Clear page and add template placeholders")
         mode_group.addButton(replace_radio, 0)
         layout.addWidget(replace_radio)
-        
+
         reflow_radio = QRadioButton("Reflow existing content")
         reflow_radio.setToolTip("Keep existing images and reposition to template slots")
         mode_group.addButton(reflow_radio, 1)
         layout.addWidget(reflow_radio)
-        
+
         layout.addSpacing(10)
-        
+
         # Margin/Spacing percentage
         layout.addWidget(QLabel("Margin/Spacing:"))
         margin_layout = QHBoxLayout()
@@ -264,9 +255,9 @@ class TemplateOperationsMixin:
         margin_layout.addWidget(margin_spinbox)
         margin_layout.addStretch()
         layout.addLayout(margin_layout)
-        
+
         layout.addSpacing(10)
-        
+
         # Scaling selection
         layout.addWidget(QLabel("Scaling:"))
         scale_group = QButtonGroup(dialog)
@@ -279,13 +270,13 @@ class TemplateOperationsMixin:
         stretch_radio.setChecked(True)
         scale_group.addButton(stretch_radio, 1)
         layout.addWidget(stretch_radio)
-        
+
         center_radio = QRadioButton("Center (no scaling)")
         scale_group.addButton(center_radio, 2)
         layout.addWidget(center_radio)
-        
+
         layout.addSpacing(20)
-        
+
         # Buttons
         button_layout = QHBoxLayout()
         cancel_btn = QPushButton("Cancel")
@@ -293,38 +284,34 @@ class TemplateOperationsMixin:
         apply_btn = QPushButton("Apply")
         apply_btn.clicked.connect(dialog.accept)
         apply_btn.setDefault(True)
-        
+
         button_layout.addStretch()
         button_layout.addWidget(cancel_btn)
         button_layout.addWidget(apply_btn)
         layout.addLayout(button_layout)
-        
+
         dialog.setLayout(layout)
-        
+
         # Show dialog
         if dialog.exec() != QDialog.DialogCode.Accepted:
             return
-        
+
         # Get selections
         template_name = template_combo.currentText()
         mode_id = mode_group.checkedId()
         scale_id = scale_group.checkedId()
         margin_percent = margin_spinbox.value()
-        
+
         mode = "replace" if mode_id == 0 else "reflow"
         scale_mode = ["proportional", "stretch", "center"][scale_id]
-        
+
         try:
             # Load template
             template = self.template_manager.load_template(template_name)
 
             # Apply template to page
             self.template_manager.apply_template_to_page(
-                template,
-                current_page,
-                mode=mode,
-                scale_mode=scale_mode,
-                margin_percent=margin_percent
+                template, current_page, mode=mode, scale_mode=scale_mode, margin_percent=margin_percent
             )
 
             # Update display
@@ -332,7 +319,7 @@ class TemplateOperationsMixin:
 
             self.show_status(f"Applied template '{template_name}' to current page", 3000)
             print(f"Applied template '{template_name}' with mode={mode}, scale_mode={scale_mode}")
-        
+
         except Exception as e:
             self.show_error("Error", f"Failed to apply template: {str(e)}")
             print(f"Error applying template: {e}")
diff --git a/pyPhotoAlbum/mixins/operations/view_ops.py b/pyPhotoAlbum/mixins/operations/view_ops.py
index 25e3c17..23ea652 100644
--- a/pyPhotoAlbum/mixins/operations/view_ops.py
+++ b/pyPhotoAlbum/mixins/operations/view_ops.py
@@ -7,14 +7,8 @@ from pyPhotoAlbum.decorators import ribbon_action
 
 class ViewOperationsMixin:
     """Mixin providing view-related operations"""
-    
-    @ribbon_action(
-        label="Zoom In",
-        tooltip="Zoom in",
-        tab="View",
-        group="Zoom",
-        shortcut="Ctrl++"
-    )
+
+    @ribbon_action(label="Zoom In", tooltip="Zoom in", tab="View", group="Zoom", shortcut="Ctrl++")
     def zoom_in(self):
         """Zoom in"""
         self.gl_widget.zoom_level *= 1.2
@@ -22,14 +16,8 @@ class ViewOperationsMixin:
             self.gl_widget.zoom_level = 5.0
         self.update_view()
         self.show_status(f"Zoom: {int(self.gl_widget.zoom_level * 100)}%", 2000)
-    
-    @ribbon_action(
-        label="Zoom Out",
-        tooltip="Zoom out",
-        tab="View",
-        group="Zoom",
-        shortcut="Ctrl+-"
-    )
+
+    @ribbon_action(label="Zoom Out", tooltip="Zoom out", tab="View", group="Zoom", shortcut="Ctrl+-")
     def zoom_out(self):
         """Zoom out"""
         self.gl_widget.zoom_level /= 1.2
@@ -37,47 +25,36 @@ class ViewOperationsMixin:
             self.gl_widget.zoom_level = 0.1
         self.update_view()
         self.show_status(f"Zoom: {int(self.gl_widget.zoom_level * 100)}%", 2000)
-    
-    @ribbon_action(
-        label="Fit to Window",
-        tooltip="Fit page to window",
-        tab="View",
-        group="Zoom",
-        shortcut="Ctrl+0"
-    )
+
+    @ribbon_action(label="Fit to Window", tooltip="Fit page to window", tab="View", group="Zoom", shortcut="Ctrl+0")
     def zoom_fit(self):
         """Fit page to window"""
         if not self.project.pages:
             return
-        
+
         current_page = self.project.pages[self.gl_widget.current_page_index]
         page_width_mm = current_page.layout.size[0]
         page_height_mm = current_page.layout.size[1]
-        
+
         # Convert to pixels
         dpi = self.project.working_dpi
         page_width_px = page_width_mm * dpi / 25.4
         page_height_px = page_height_mm * dpi / 25.4
-        
+
         # Get widget size
         widget_width = self.gl_widget.width() - 100  # Margins
         widget_height = self.gl_widget.height() - 100
-        
+
         # Calculate zoom to fit
         zoom_w = widget_width / page_width_px
         zoom_h = widget_height / page_height_px
-        
+
         self.gl_widget.zoom_level = min(zoom_w, zoom_h)
         self.gl_widget.zoom_level = max(0.1, min(5.0, self.gl_widget.zoom_level))
         self.update_view()
         self.show_status(f"Zoom: {int(self.gl_widget.zoom_level * 100)}%", 2000)
-    
-    @ribbon_action(
-        label="Toggle Grid Snap",
-        tooltip="Toggle snapping to grid",
-        tab="View",
-        group="Snapping"
-    )
+
+    @ribbon_action(label="Toggle Grid Snap", tooltip="Toggle snapping to grid", tab="View", group="Snapping")
     def toggle_grid_snap(self):
         """Toggle grid snapping"""
         if not self.project:
@@ -89,13 +66,8 @@ class ViewOperationsMixin:
         self.update_view()
         self.show_status(f"Grid snapping {status}", 2000)
         print(f"Grid snapping {status}")
-    
-    @ribbon_action(
-        label="Toggle Edge Snap",
-        tooltip="Toggle snapping to page edges",
-        tab="View",
-        group="Snapping"
-    )
+
+    @ribbon_action(label="Toggle Edge Snap", tooltip="Toggle snapping to page edges", tab="View", group="Snapping")
     def toggle_edge_snap(self):
         """Toggle edge snapping"""
         if not self.project:
@@ -107,13 +79,8 @@ class ViewOperationsMixin:
         self.update_view()
         self.show_status(f"Edge snapping {status}", 2000)
         print(f"Edge snapping {status}")
-    
-    @ribbon_action(
-        label="Toggle Guide Snap",
-        tooltip="Toggle snapping to guides",
-        tab="View",
-        group="Snapping"
-    )
+
+    @ribbon_action(label="Toggle Guide Snap", tooltip="Toggle snapping to guides", tab="View", group="Snapping")
     def toggle_guide_snap(self):
         """Toggle guide snapping"""
         if not self.project:
@@ -125,13 +92,8 @@ class ViewOperationsMixin:
         self.update_view()
         self.show_status(f"Guide snapping {status}", 2000)
         print(f"Guide snapping {status}")
-    
-    @ribbon_action(
-        label="Show Grid",
-        tooltip="Toggle visibility of grid lines",
-        tab="View",
-        group="Snapping"
-    )
+
+    @ribbon_action(label="Show Grid", tooltip="Toggle visibility of grid lines", tab="View", group="Snapping")
     def toggle_show_grid(self):
         """Toggle grid visibility"""
         if not self.project:
@@ -144,12 +106,7 @@ class ViewOperationsMixin:
         self.show_status(f"Grid {status}", 2000)
         print(f"Grid {status}")
 
-    @ribbon_action(
-        label="Show Guides",
-        tooltip="Toggle visibility of guide lines",
-        tab="View",
-        group="Snapping"
-    )
+    @ribbon_action(label="Show Guides", tooltip="Toggle visibility of guide lines", tab="View", group="Snapping")
     def toggle_snap_lines(self):
         """Toggle guide lines visibility"""
         if not self.project:
@@ -161,71 +118,53 @@ class ViewOperationsMixin:
         self.update_view()
         self.show_status(f"Guides {status}", 2000)
         print(f"Guides {status}")
-    
-    @ribbon_action(
-        label="Add H Guide",
-        tooltip="Add horizontal guide at page center",
-        tab="View",
-        group="Guides"
-    )
+
+    @ribbon_action(label="Add H Guide", tooltip="Add horizontal guide at page center", tab="View", group="Guides")
     def add_horizontal_guide(self):
         """Add a horizontal guide at page center"""
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         # Add guide at vertical center (in mm)
         center_y = current_page.layout.size[1] / 2.0
-        current_page.layout.snapping_system.add_guide(center_y, 'horizontal')
-        
+        current_page.layout.snapping_system.add_guide(center_y, "horizontal")
+
         self.update_view()
         self.show_status(f"Added horizontal guide at {center_y:.1f} mm", 2000)
         print(f"Added horizontal guide at {center_y:.1f} mm")
-    
-    @ribbon_action(
-        label="Add V Guide",
-        tooltip="Add vertical guide at page center",
-        tab="View",
-        group="Guides"
-    )
+
+    @ribbon_action(label="Add V Guide", tooltip="Add vertical guide at page center", tab="View", group="Guides")
     def add_vertical_guide(self):
         """Add a vertical guide at page center"""
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         # Add guide at horizontal center (in mm)
         center_x = current_page.layout.size[0] / 2.0
-        current_page.layout.snapping_system.add_guide(center_x, 'vertical')
-        
+        current_page.layout.snapping_system.add_guide(center_x, "vertical")
+
         self.update_view()
         self.show_status(f"Added vertical guide at {center_x:.1f} mm", 2000)
         print(f"Added vertical guide at {center_x:.1f} mm")
-    
-    @ribbon_action(
-        label="Clear Guides",
-        tooltip="Clear all guides from current page",
-        tab="View",
-        group="Guides"
-    )
+
+    @ribbon_action(label="Clear Guides", tooltip="Clear all guides from current page", tab="View", group="Guides")
     def clear_guides(self):
         """Clear all guides from current page"""
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         guide_count = len(current_page.layout.snapping_system.guides)
         current_page.layout.snapping_system.clear_guides()
-        
+
         self.update_view()
         self.show_status(f"Cleared {guide_count} guides", 2000)
         print(f"Cleared {guide_count} guides")
-    
+
     @ribbon_action(
-        label="Set Grid Size...",
-        tooltip="Configure grid spacing for snapping",
-        tab="View",
-        group="Snapping"
+        label="Set Grid Size...", tooltip="Configure grid spacing for snapping", tab="View", group="Snapping"
     )
     def set_grid_size(self):
         """Open dialog to set grid size"""
@@ -295,67 +234,49 @@ class ViewOperationsMixin:
             self.update_view()
             self.show_status(f"Grid size: {new_grid_size:.1f}mm, Threshold: {new_threshold:.1f}mm", 2000)
             print(f"Updated grid settings - Size: {new_grid_size:.1f}mm, Threshold: {new_threshold:.1f}mm")
-    
+
     # ===== Layout Tab Snapping Controls =====
     # These provide easy access to snapping features during layout work
-    
+
     @ribbon_action(
         label="Grid Snap",
         tooltip="Enable/disable snapping to grid (Ctrl+G)",
         tab="Layout",
         group="Snapping",
-        shortcut="Ctrl+G"
+        shortcut="Ctrl+G",
     )
     def layout_toggle_grid_snap(self):
         """Toggle grid snapping (Layout tab)"""
         self.toggle_grid_snap()
-    
+
     @ribbon_action(
         label="Edge Snap",
         tooltip="Enable/disable snapping to page edges (Ctrl+E)",
         tab="Layout",
         group="Snapping",
-        shortcut="Ctrl+E"
+        shortcut="Ctrl+E",
     )
     def layout_toggle_edge_snap(self):
         """Toggle edge snapping (Layout tab)"""
         self.toggle_edge_snap()
-    
-    @ribbon_action(
-        label="Guide Snap",
-        tooltip="Enable/disable snapping to guides",
-        tab="Layout",
-        group="Snapping"
-    )
+
+    @ribbon_action(label="Guide Snap", tooltip="Enable/disable snapping to guides", tab="Layout", group="Snapping")
     def layout_toggle_guide_snap(self):
         """Toggle guide snapping (Layout tab)"""
         self.toggle_guide_snap()
-    
-    @ribbon_action(
-        label="Show Grid",
-        tooltip="Toggle visibility of grid lines",
-        tab="Layout",
-        group="Snapping"
-    )
+
+    @ribbon_action(label="Show Grid", tooltip="Toggle visibility of grid lines", tab="Layout", group="Snapping")
     def layout_toggle_show_grid(self):
         """Toggle grid visibility (Layout tab)"""
         self.toggle_show_grid()
 
-    @ribbon_action(
-        label="Show Guides",
-        tooltip="Toggle visibility of guide lines",
-        tab="Layout",
-        group="Snapping"
-    )
+    @ribbon_action(label="Show Guides", tooltip="Toggle visibility of guide lines", tab="Layout", group="Snapping")
     def layout_toggle_snap_lines(self):
         """Toggle guide lines visibility (Layout tab)"""
         self.toggle_snap_lines()
-    
+
     @ribbon_action(
-        label="Grid Settings...",
-        tooltip="Configure grid size and snap threshold",
-        tab="Layout",
-        group="Snapping"
+        label="Grid Settings...", tooltip="Configure grid size and snap threshold", tab="Layout", group="Snapping"
     )
     def layout_set_grid_size(self):
         """Open grid settings dialog (Layout tab)"""
diff --git a/pyPhotoAlbum/mixins/operations/zorder_ops.py b/pyPhotoAlbum/mixins/operations/zorder_ops.py
index 10c0d3c..e2117d3 100644
--- a/pyPhotoAlbum/mixins/operations/zorder_ops.py
+++ b/pyPhotoAlbum/mixins/operations/zorder_ops.py
@@ -8,159 +8,159 @@ from pyPhotoAlbum.commands import ChangeZOrderCommand
 
 class ZOrderOperationsMixin:
     """Mixin providing z-order/layer control operations"""
-    
+
     @ribbon_action(
         label="Bring to Front",
         tooltip="Bring selected element to front",
         tab="Arrange",
         group="Order",
         shortcut="Ctrl+Shift+]",
-        requires_selection=True
+        requires_selection=True,
     )
     def bring_to_front(self):
         """Bring selected element to front (end of list)"""
         if not self.gl_widget.selected_element:
             return
-        
+
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         element = self.gl_widget.selected_element
         elements = current_page.layout.elements
-        
+
         if element not in elements:
             return
-        
+
         old_index = elements.index(element)
         new_index = len(elements) - 1
-        
+
         if old_index == new_index:
             self.show_status("Element is already at front", 2000)
             return
-        
+
         # Create and execute command
         cmd = ChangeZOrderCommand(current_page.layout, element, old_index, new_index)
         self.project.history.execute(cmd)
-        
+
         self.update_view()
         self.show_status("Brought element to front (Ctrl+Z to undo)", 2000)
         print(f"Brought element to front: {old_index} → {new_index}")
-    
+
     @ribbon_action(
         label="Send to Back",
         tooltip="Send selected element to back",
         tab="Arrange",
         group="Order",
         shortcut="Ctrl+Shift+[",
-        requires_selection=True
+        requires_selection=True,
     )
     def send_to_back(self):
         """Send selected element to back (start of list)"""
         if not self.gl_widget.selected_element:
             return
-        
+
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         element = self.gl_widget.selected_element
         elements = current_page.layout.elements
-        
+
         if element not in elements:
             return
-        
+
         old_index = elements.index(element)
         new_index = 0
-        
+
         if old_index == new_index:
             self.show_status("Element is already at back", 2000)
             return
-        
+
         # Create and execute command
         cmd = ChangeZOrderCommand(current_page.layout, element, old_index, new_index)
         self.project.history.execute(cmd)
-        
+
         self.update_view()
         self.show_status("Sent element to back (Ctrl+Z to undo)", 2000)
         print(f"Sent element to back: {old_index} → {new_index}")
-    
+
     @ribbon_action(
         label="Bring Forward",
         tooltip="Bring selected element forward one layer",
         tab="Arrange",
         group="Order",
         shortcut="Ctrl+]",
-        requires_selection=True
+        requires_selection=True,
     )
     def bring_forward(self):
         """Move selected element forward one position in list"""
         if not self.gl_widget.selected_element:
             return
-        
+
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         element = self.gl_widget.selected_element
         elements = current_page.layout.elements
-        
+
         if element not in elements:
             return
-        
+
         old_index = elements.index(element)
         new_index = old_index + 1
-        
+
         if new_index >= len(elements):
             self.show_status("Element is already at front", 2000)
             return
-        
+
         # Create and execute command
         cmd = ChangeZOrderCommand(current_page.layout, element, old_index, new_index)
         self.project.history.execute(cmd)
-        
+
         self.update_view()
         self.show_status("Brought element forward (Ctrl+Z to undo)", 2000)
         print(f"Brought element forward: {old_index} → {new_index}")
-    
+
     @ribbon_action(
         label="Send Backward",
         tooltip="Send selected element backward one layer",
         tab="Arrange",
         group="Order",
         shortcut="Ctrl+[",
-        requires_selection=True
+        requires_selection=True,
     )
     def send_backward(self):
         """Move selected element backward one position in list"""
         if not self.gl_widget.selected_element:
             return
-        
+
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         element = self.gl_widget.selected_element
         elements = current_page.layout.elements
-        
+
         if element not in elements:
             return
-        
+
         old_index = elements.index(element)
         new_index = old_index - 1
-        
+
         if new_index < 0:
             self.show_status("Element is already at back", 2000)
             return
-        
+
         # Create and execute command
         cmd = ChangeZOrderCommand(current_page.layout, element, old_index, new_index)
         self.project.history.execute(cmd)
-        
+
         self.update_view()
         self.show_status("Sent element backward (Ctrl+Z to undo)", 2000)
         print(f"Sent element backward: {old_index} → {new_index}")
-    
+
     @ribbon_action(
         label="Swap Order",
         tooltip="Swap z-order of two selected elements",
@@ -168,21 +168,21 @@ class ZOrderOperationsMixin:
         group="Order",
         shortcut="Ctrl+Shift+X",
         requires_selection=True,
-        min_selection=2
+        min_selection=2,
     )
     def swap_order(self):
         """Swap the z-order of two selected elements"""
         if len(self.gl_widget.selected_elements) != 2:
             self.show_status("Please select exactly 2 elements to swap", 2000)
             return
-        
+
         current_page = self.get_current_page()
         if not current_page:
             return
-        
+
         elements = current_page.layout.elements
         selected = list(self.gl_widget.selected_elements)
-        
+
         # Get indices of both elements
         try:
             index1 = elements.index(selected[0])
@@ -190,10 +190,10 @@ class ZOrderOperationsMixin:
         except ValueError:
             self.show_status("Selected elements not found on current page", 2000)
             return
-        
+
         # Swap them in the list
         elements[index1], elements[index2] = elements[index2], elements[index1]
-        
+
         self.update_view()
         self.show_status(f"Swapped z-order of elements", 2000)
         print(f"Swapped elements at indices {index1} and {index2}")
diff --git a/pyPhotoAlbum/mixins/page_navigation.py b/pyPhotoAlbum/mixins/page_navigation.py
index b97abec..5e10d44 100644
--- a/pyPhotoAlbum/mixins/page_navigation.py
+++ b/pyPhotoAlbum/mixins/page_navigation.py
@@ -33,11 +33,11 @@ class PageNavigationMixin:
         Returns:
             Tuple of (page, page_index, renderer) or (None, -1, None) if no page at coordinates
         """
-        if not hasattr(self, '_page_renderers') or not self._page_renderers:
+        if not hasattr(self, "_page_renderers") or not self._page_renderers:
             return None, -1, None
 
         main_window = self.window()
-        if not hasattr(main_window, 'project') or not main_window.project or not main_window.project.pages:
+        if not hasattr(main_window, "project") or not main_window.project or not main_window.project.pages:
             return None, -1, None
 
         # Check each page to find which one contains the coordinates
@@ -57,7 +57,7 @@ class PageNavigationMixin:
             List of tuples (page_type, page_or_ghost_data, y_offset)
         """
         main_window = self.window()
-        if not hasattr(main_window, 'project'):
+        if not hasattr(main_window, "project"):
             return []
 
         dpi = main_window.project.working_dpi
@@ -77,7 +77,7 @@ class PageNavigationMixin:
         # First, render cover if it exists
         for page in main_window.project.pages:
             if page.is_cover:
-                result.append(('page', page, current_y))
+                result.append(("page", page, current_y))
 
                 # Calculate cover height in pixels
                 page_height_mm = page.layout.size[1]
@@ -91,7 +91,7 @@ class PageNavigationMixin:
         layout_with_ghosts = main_window.project.calculate_page_layout_with_ghosts()
 
         for page_type, page_obj, logical_pos in layout_with_ghosts:
-            if page_type == 'page':
+            if page_type == "page":
                 # Regular page (single or double spread)
                 result.append((page_type, page_obj, current_y))
 
@@ -103,7 +103,7 @@ class PageNavigationMixin:
                 # Move to next position (add height + spacing)
                 current_y += page_height_px + spacing_px
 
-            elif page_type == 'ghost':
+            elif page_type == "ghost":
                 # Ghost page - use default page size
                 page_size_mm = main_window.project.page_size_mm
                 from pyPhotoAlbum.models import GhostPageData
@@ -131,11 +131,11 @@ class PageNavigationMixin:
         Returns:
             bool: True if a ghost page was clicked and a new page was created
         """
-        if not hasattr(self, '_page_renderers'):
+        if not hasattr(self, "_page_renderers"):
             return False
 
         main_window = self.window()
-        if not hasattr(main_window, 'project'):
+        if not hasattr(main_window, "project"):
             return False
 
         # Get page positions which includes ghosts
@@ -144,7 +144,7 @@ class PageNavigationMixin:
         # Check each position for ghost pages
         for idx, (page_type, page_or_ghost, y_offset) in enumerate(page_positions):
             # Skip non-ghost pages
-            if page_type != 'ghost':
+            if page_type != "ghost":
                 continue
 
             ghost = page_or_ghost
@@ -156,20 +156,21 @@ class PageNavigationMixin:
             screen_y = (y_offset * self.zoom_level) + self.pan_offset[1]
 
             from pyPhotoAlbum.page_renderer import PageRenderer
+
             renderer = PageRenderer(
                 page_width_mm=ghost_width_mm,
                 page_height_mm=ghost_height_mm,
                 screen_x=screen_x,
                 screen_y=screen_y,
                 dpi=dpi,
-                zoom=self.zoom_level
+                zoom=self.zoom_level,
             )
 
             # Check if click is anywhere on the ghost page (entire page is clickable)
             if renderer.is_point_in_page(x, y):
                 # User clicked the ghost page!
                 # Calculate the insertion index (count real pages before this ghost in page_positions)
-                insert_index = sum(1 for i, (pt, _, _) in enumerate(page_positions) if i < idx and pt == 'page')
+                insert_index = sum(1 for i, (pt, _, _) in enumerate(page_positions) if i < idx and pt == "page")
 
                 print(f"Ghost page clicked at index {insert_index} - inserting new page in place")
 
@@ -181,10 +182,9 @@ class PageNavigationMixin:
                 new_page_number = insert_index + 1
                 new_page = Page(
                     layout=PageLayout(
-                        width=main_window.project.page_size_mm[0],
-                        height=main_window.project.page_size_mm[1]
+                        width=main_window.project.page_size_mm[0], height=main_window.project.page_size_mm[1]
                     ),
-                    page_number=new_page_number
+                    page_number=new_page_number,
                 )
 
                 # Insert the page at the correct position
@@ -209,10 +209,10 @@ class PageNavigationMixin:
             y: Screen Y coordinate
         """
         main_window = self.window()
-        if not hasattr(main_window, 'project') or not main_window.project or not main_window.project.pages:
+        if not hasattr(main_window, "project") or not main_window.project or not main_window.project.pages:
             return
 
-        if not hasattr(self, '_page_renderers') or not self._page_renderers:
+        if not hasattr(self, "_page_renderers") or not self._page_renderers:
             return
 
         # Get total page count (accounting for double spreads = 2 pages each)
@@ -228,7 +228,7 @@ class PageNavigationMixin:
                 if page.is_double_spread:
                     side = renderer.get_sub_page_at(x, is_facing_page=True)
                     page_nums = page.get_page_numbers()
-                    if side == 'left':
+                    if side == "left":
                         current_page_info = f"Page {page_nums[0]}"
                     else:
                         current_page_info = f"Page {page_nums[1]}"
@@ -237,8 +237,10 @@ class PageNavigationMixin:
                 break
 
         # Update status bar
-        if hasattr(main_window, 'status_bar'):
+        if hasattr(main_window, "status_bar"):
             if current_page_info:
-                main_window.status_bar.showMessage(f"{current_page_info} of {total_pages} | Zoom: {int(self.zoom_level * 100)}%")
+                main_window.status_bar.showMessage(
+                    f"{current_page_info} of {total_pages} | Zoom: {int(self.zoom_level * 100)}%"
+                )
             else:
                 main_window.status_bar.showMessage(f"Total pages: {total_pages} | Zoom: {int(self.zoom_level * 100)}%")
diff --git a/pyPhotoAlbum/mixins/rendering.py b/pyPhotoAlbum/mixins/rendering.py
index 184c2ea..7fa6ff2 100644
--- a/pyPhotoAlbum/mixins/rendering.py
+++ b/pyPhotoAlbum/mixins/rendering.py
@@ -26,7 +26,7 @@ class RenderingMixin:
         glLoadIdentity()
 
         main_window = self.window()
-        if not hasattr(main_window, 'project') or not main_window.project or not main_window.project.pages:
+        if not hasattr(main_window, "project") or not main_window.project or not main_window.project.pages:
             return
 
         # Set initial zoom and center the page if not done yet
@@ -37,7 +37,7 @@ class RenderingMixin:
 
             # Update scrollbars now that we have content bounds
             main_window = self.window()
-            if hasattr(main_window, 'update_scrollbars'):
+            if hasattr(main_window, "update_scrollbars"):
                 main_window.update_scrollbars()
 
         dpi = main_window.project.working_dpi
@@ -55,7 +55,7 @@ class RenderingMixin:
         for page_info in page_positions:
             page_type, page_or_ghost, y_offset = page_info
 
-            if page_type == 'page':
+            if page_type == "page":
                 page = page_or_ghost
                 page_width_mm, page_height_mm = page.layout.size
 
@@ -68,7 +68,7 @@ class RenderingMixin:
                     screen_x=screen_x,
                     screen_y=screen_y,
                     dpi=dpi,
-                    zoom=self.zoom_level
+                    zoom=self.zoom_level,
                 )
 
                 self._page_renderers.append((renderer, page))
@@ -79,7 +79,7 @@ class RenderingMixin:
                 page.layout.render(dpi=dpi, project=main_window.project)
                 renderer.end_render()
 
-            elif page_type == 'ghost':
+            elif page_type == "ghost":
                 ghost = page_or_ghost
                 ghost_width_mm, ghost_height_mm = ghost.page_size
 
@@ -92,14 +92,14 @@ class RenderingMixin:
                     screen_x=screen_x,
                     screen_y=screen_y,
                     dpi=dpi,
-                    zoom=self.zoom_level
+                    zoom=self.zoom_level,
                 )
 
                 self._render_ghost_page(ghost, renderer)
 
         # Update PageRenderer references for selected elements
         for element in self.selected_elements:
-            if hasattr(element, '_parent_page'):
+            if hasattr(element, "_parent_page"):
                 for renderer, page in self._page_renderers:
                     if page is element._parent_page:
                         element._page_renderer = renderer
@@ -118,10 +118,10 @@ class RenderingMixin:
             return
 
         main_window = self.window()
-        if not hasattr(main_window, 'project') or not main_window.project or not main_window.project.pages:
+        if not hasattr(main_window, "project") or not main_window.project or not main_window.project.pages:
             return
 
-        if not hasattr(element, '_page_renderer'):
+        if not hasattr(element, "_page_renderer"):
             return
 
         renderer = element._page_renderer
@@ -188,10 +188,10 @@ class RenderingMixin:
                 glEnd()
         else:
             handles = [
-                (x - handle_size/2, y - handle_size/2),
-                (x + w - handle_size/2, y - handle_size/2),
-                (x - handle_size/2, y + h - handle_size/2),
-                (x + w - handle_size/2, y + h - handle_size/2),
+                (x - handle_size / 2, y - handle_size / 2),
+                (x + w - handle_size / 2, y - handle_size / 2),
+                (x - handle_size / 2, y + h - handle_size / 2),
+                (x + w - handle_size / 2, y + h - handle_size / 2),
             ]
 
             glColor3f(1.0, 1.0, 1.0)
@@ -214,7 +214,7 @@ class RenderingMixin:
 
     def _render_text_overlays(self):
         """Render text content for TextBoxData elements using QPainter overlay"""
-        if not hasattr(self, '_page_renderers') or not self._page_renderers:
+        if not hasattr(self, "_page_renderers") or not self._page_renderers:
             return
 
         painter = QPainter(self)
@@ -236,12 +236,12 @@ class RenderingMixin:
                     screen_w = w * renderer.zoom
                     screen_h = h * renderer.zoom
 
-                    font_family = element.font_settings.get('family', 'Arial')
-                    font_size = int(element.font_settings.get('size', 12) * renderer.zoom)
+                    font_family = element.font_settings.get("family", "Arial")
+                    font_size = int(element.font_settings.get("size", 12) * renderer.zoom)
                     font = QFont(font_family, font_size)
                     painter.setFont(font)
 
-                    font_color = element.font_settings.get('color', (0, 0, 0))
+                    font_color = element.font_settings.get("color", (0, 0, 0))
                     if all(isinstance(c, int) and c > 1 for c in font_color):
                         color = QColor(*font_color)
                     else:
@@ -260,9 +260,9 @@ class RenderingMixin:
                         rect = QRectF(screen_x, screen_y, screen_w, screen_h)
 
                     alignment = Qt.AlignmentFlag.AlignLeft | Qt.AlignmentFlag.AlignTop
-                    if element.alignment == 'center':
+                    if element.alignment == "center":
                         alignment = Qt.AlignmentFlag.AlignHCenter | Qt.AlignmentFlag.AlignTop
-                    elif element.alignment == 'right':
+                    elif element.alignment == "right":
                         alignment = Qt.AlignmentFlag.AlignRight | Qt.AlignmentFlag.AlignTop
 
                     text_flags = Qt.TextFlag.TextWordWrap
diff --git a/pyPhotoAlbum/mixins/viewport.py b/pyPhotoAlbum/mixins/viewport.py
index 99d44e7..80bb88d 100644
--- a/pyPhotoAlbum/mixins/viewport.py
+++ b/pyPhotoAlbum/mixins/viewport.py
@@ -61,7 +61,7 @@ class ViewportMixin:
 
         # Update scrollbars when viewport size changes
         main_window = self.window()
-        if hasattr(main_window, 'update_scrollbars'):
+        if hasattr(main_window, "update_scrollbars"):
             main_window.update_scrollbars()
 
     def _calculate_fit_to_screen_zoom(self):
@@ -72,7 +72,7 @@ class ViewportMixin:
             float: Zoom level (1.0 = 100%, 0.5 = 50%, etc.)
         """
         main_window = self.window()
-        if not hasattr(main_window, 'project') or not main_window.project or not main_window.project.pages:
+        if not hasattr(main_window, "project") or not main_window.project or not main_window.project.pages:
             return 1.0
 
         window_width = self.width()
@@ -106,7 +106,7 @@ class ViewportMixin:
             list: [x_offset, y_offset] to center the page
         """
         main_window = self.window()
-        if not hasattr(main_window, 'project') or not main_window.project or not main_window.project.pages:
+        if not hasattr(main_window, "project") or not main_window.project or not main_window.project.pages:
             return [0, 0]
 
         window_width = self.width()
@@ -141,8 +141,8 @@ class ViewportMixin:
             dict: {'min_x', 'max_x', 'min_y', 'max_y', 'width', 'height'} in pixels
         """
         main_window = self.window()
-        if not hasattr(main_window, 'project') or not main_window.project or not main_window.project.pages:
-            return {'min_x': 0, 'max_x': 800, 'min_y': 0, 'max_y': 600, 'width': 800, 'height': 600}
+        if not hasattr(main_window, "project") or not main_window.project or not main_window.project.pages:
+            return {"min_x": 0, "max_x": 800, "min_y": 0, "max_y": 600, "width": 800, "height": 600}
 
         dpi = main_window.project.working_dpi
         PAGE_MARGIN = 50
@@ -167,12 +167,12 @@ class ViewportMixin:
         total_height += PAGE_MARGIN
 
         return {
-            'min_x': 0,
-            'max_x': total_width,
-            'min_y': 0,
-            'max_y': total_height,
-            'width': total_width,
-            'height': total_height
+            "min_x": 0,
+            "max_x": total_width,
+            "min_y": 0,
+            "max_y": total_height,
+            "width": total_width,
+            "height": total_height,
         }
 
     def clamp_pan_offset(self):
@@ -188,7 +188,7 @@ class ViewportMixin:
         when zooming on pages of different widths.
         """
         main_window = self.window()
-        if not hasattr(main_window, 'project') or not main_window.project or not main_window.project.pages:
+        if not hasattr(main_window, "project") or not main_window.project or not main_window.project.pages:
             return
 
         viewport_width = self.width()
@@ -200,7 +200,7 @@ class ViewportMixin:
 
         # Vertical clamping
         bounds = self.get_content_bounds()
-        content_height = bounds['height']
+        content_height = bounds["height"]
 
         # Save original pan_offset[1] BEFORE clamping for page selection
         # This prevents clamping from changing which page we think we're on
diff --git a/pyPhotoAlbum/models.py b/pyPhotoAlbum/models.py
index b5acf21..7dbb23f 100644
--- a/pyPhotoAlbum/models.py
+++ b/pyPhotoAlbum/models.py
@@ -13,13 +13,39 @@ from PIL import Image
 
 from pyPhotoAlbum.image_utils import apply_pil_rotation, calculate_center_crop_coords
 from pyPhotoAlbum.gl_imports import (
-    GL_AVAILABLE, glBegin, glEnd, glVertex2f, glColor3f, glColor4f,
-    GL_QUADS, GL_LINE_LOOP, glEnable, glDisable, GL_TEXTURE_2D,
-    glBindTexture, glTexCoord2f, glTexParameteri, GL_TEXTURE_MIN_FILTER,
-    GL_TEXTURE_MAG_FILTER, GL_LINEAR, glGenTextures, glTexImage2D,
-    GL_RGBA, GL_UNSIGNED_BYTE, glDeleteTextures, glGetString, GL_VERSION,
-    glLineStipple, GL_LINE_STIPPLE, glPushMatrix, glPopMatrix,
-    glTranslatef, glRotatef, GL_BLEND, glBlendFunc, GL_SRC_ALPHA,
+    GL_AVAILABLE,
+    glBegin,
+    glEnd,
+    glVertex2f,
+    glColor3f,
+    glColor4f,
+    GL_QUADS,
+    GL_LINE_LOOP,
+    glEnable,
+    glDisable,
+    GL_TEXTURE_2D,
+    glBindTexture,
+    glTexCoord2f,
+    glTexParameteri,
+    GL_TEXTURE_MIN_FILTER,
+    GL_TEXTURE_MAG_FILTER,
+    GL_LINEAR,
+    glGenTextures,
+    glTexImage2D,
+    GL_RGBA,
+    GL_UNSIGNED_BYTE,
+    glDeleteTextures,
+    glGetString,
+    GL_VERSION,
+    glLineStipple,
+    GL_LINE_STIPPLE,
+    glPushMatrix,
+    glPopMatrix,
+    glTranslatef,
+    glRotatef,
+    GL_BLEND,
+    glBlendFunc,
+    GL_SRC_ALPHA,
     GL_ONE_MINUS_SRC_ALPHA,
 )
 
@@ -48,10 +74,13 @@ def get_asset_search_paths() -> Tuple[Optional[str], List[str]]:
     """Get the current asset resolution context."""
     return _primary_project_folder, _asset_search_paths
 
+
 class BaseLayoutElement(ABC):
     """Abstract base class for all layout elements"""
 
-    def __init__(self, x: float = 0, y: float = 0, width: float = 100, height: float = 100, rotation: float = 0, z_index: int = 0):
+    def __init__(
+        self, x: float = 0, y: float = 0, width: float = 100, height: float = 100, rotation: float = 0, z_index: int = 0
+    ):
         self.position = (x, y)
         self.size = (width, height)
         self.rotation = rotation
@@ -118,11 +147,17 @@ class BaseLayoutElement(ABC):
         """Deserialize from a dictionary"""
         pass
 
+
 class ImageData(BaseLayoutElement):
     """Class to store image data and properties"""
 
-    def __init__(self, image_path: str = "", crop_info: Optional[Tuple] = None,
-                 image_dimensions: Optional[Tuple[int, int]] = None, **kwargs):
+    def __init__(
+        self,
+        image_path: str = "",
+        crop_info: Optional[Tuple] = None,
+        image_dimensions: Optional[Tuple[int, int]] = None,
+        **kwargs,
+    ):
         super().__init__(**kwargs)
         self.image_path = image_path
         self.crop_info = crop_info or (0, 0, 1, 1)  # Default: no crop
@@ -190,15 +225,15 @@ class ImageData(BaseLayoutElement):
 
         # Create texture from pending image if one exists (deferred from async load)
         # Texture creation must happen during render when GL context is active
-        if hasattr(self, '_pending_pil_image') and self._pending_pil_image is not None:
+        if hasattr(self, "_pending_pil_image") and self._pending_pil_image is not None:
             self._create_texture_from_pending_image()
 
         # Use cached texture if available
-        if hasattr(self, '_texture_id') and self._texture_id:
+        if hasattr(self, "_texture_id") and self._texture_id:
             texture_id = self._texture_id
 
             # Get image dimensions (from loaded texture or metadata)
-            if hasattr(self, '_img_width') and hasattr(self, '_img_height'):
+            if hasattr(self, "_img_width") and hasattr(self, "_img_height"):
                 img_width, img_height = self._img_width, self._img_height
             elif self.image_dimensions:
                 img_width, img_height = self.image_dimensions
@@ -207,9 +242,7 @@ class ImageData(BaseLayoutElement):
                 img_width, img_height = int(w), int(h)
 
             # Calculate texture coordinates for center crop with element's crop_info
-            tx_min, ty_min, tx_max, ty_max = calculate_center_crop_coords(
-                img_width, img_height, w, h, self.crop_info
-            )
+            tx_min, ty_min, tx_max, ty_max = calculate_center_crop_coords(img_width, img_height, w, h, self.crop_info)
 
             # Enable texturing and draw with crop
             glEnable(GL_TEXTURE_2D)
@@ -217,14 +250,18 @@ class ImageData(BaseLayoutElement):
             glColor4f(1.0, 1.0, 1.0, 1.0)  # White color to show texture as-is
 
             glBegin(GL_QUADS)
-            glTexCoord2f(tx_min, ty_min); glVertex2f(x, y)
-            glTexCoord2f(tx_max, ty_min); glVertex2f(x + w, y)
-            glTexCoord2f(tx_max, ty_max); glVertex2f(x + w, y + h)
-            glTexCoord2f(tx_min, ty_max); glVertex2f(x, y + h)
+            glTexCoord2f(tx_min, ty_min)
+            glVertex2f(x, y)
+            glTexCoord2f(tx_max, ty_min)
+            glVertex2f(x + w, y)
+            glTexCoord2f(tx_max, ty_max)
+            glVertex2f(x + w, y + h)
+            glTexCoord2f(tx_min, ty_max)
+            glVertex2f(x, y + h)
             glEnd()
 
             glDisable(GL_TEXTURE_2D)
-        
+
         # If no image or loading failed, draw placeholder
         if not texture_id:
             glColor3f(0.7, 0.85, 1.0)  # Light blue
@@ -234,7 +271,7 @@ class ImageData(BaseLayoutElement):
             glVertex2f(x + w, y + h)
             glVertex2f(x, y + h)
             glEnd()
-        
+
         # Draw border
         glColor3f(0.0, 0.0, 0.0)  # Black border
         glBegin(GL_LINE_LOOP)
@@ -254,7 +291,7 @@ class ImageData(BaseLayoutElement):
             "z_index": self.z_index,
             "image_path": self.image_path,
             "crop_info": self.crop_info,
-            "pil_rotation_90": getattr(self, 'pil_rotation_90', 0)
+            "pil_rotation_90": getattr(self, "pil_rotation_90", 0),
         }
         # Include image dimensions metadata if available
         if self.image_dimensions:
@@ -313,7 +350,7 @@ class ImageData(BaseLayoutElement):
             logger.debug(f"ImageData: Async load completed for {self.image_path}, size: {pil_image.size}")
 
             # Apply PIL-level rotation if needed
-            if hasattr(self, 'pil_rotation_90') and self.pil_rotation_90 > 0:
+            if hasattr(self, "pil_rotation_90") and self.pil_rotation_90 > 0:
                 pil_image = apply_pil_rotation(pil_image, self.pil_rotation_90)
                 logger.debug(f"ImageData: Applied PIL rotation {self.pil_rotation_90 * 90}° to {self.image_path}")
 
@@ -339,7 +376,7 @@ class ImageData(BaseLayoutElement):
         Create OpenGL texture from pending PIL image.
         Called during render() when GL context is active.
         """
-        if not hasattr(self, '_pending_pil_image') or self._pending_pil_image is None:
+        if not hasattr(self, "_pending_pil_image") or self._pending_pil_image is None:
             return False
 
         try:
@@ -355,11 +392,11 @@ class ImageData(BaseLayoutElement):
             pil_image = self._pending_pil_image
 
             # Ensure RGBA format for GL_RGBA texture (defensive check)
-            if pil_image.mode != 'RGBA':
-                pil_image = pil_image.convert('RGBA')
+            if pil_image.mode != "RGBA":
+                pil_image = pil_image.convert("RGBA")
 
             # Delete old texture if it exists
-            if hasattr(self, '_texture_id') and self._texture_id:
+            if hasattr(self, "_texture_id") and self._texture_id:
                 glDeleteTextures([self._texture_id])
 
             # Create GPU texture from pre-processed PIL image
@@ -369,8 +406,9 @@ class ImageData(BaseLayoutElement):
             glBindTexture(GL_TEXTURE_2D, texture_id)
             glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR)
             glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR)
-            glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, pil_image.width, pil_image.height,
-                        0, GL_RGBA, GL_UNSIGNED_BYTE, img_data)
+            glTexImage2D(
+                GL_TEXTURE_2D, 0, GL_RGBA, pil_image.width, pil_image.height, 0, GL_RGBA, GL_UNSIGNED_BYTE, img_data
+            )
 
             # Cache texture
             self._texture_id = texture_id
@@ -380,8 +418,8 @@ class ImageData(BaseLayoutElement):
             self._pending_pil_image = None
 
             # Clear the warning flag if we successfully created the texture
-            if hasattr(self, '_gl_context_warned'):
-                delattr(self, '_gl_context_warned')
+            if hasattr(self, "_gl_context_warned"):
+                delattr(self, "_gl_context_warned")
 
             logger.info(f"ImageData: Successfully created texture for {self.image_path}")
             return True
@@ -390,11 +428,13 @@ class ImageData(BaseLayoutElement):
             error_str = str(e)
             # Check if this is a GL context error (err 1282 = GL_INVALID_OPERATION)
             # These are typically caused by no GL context being current
-            if 'GLError' in error_str and '1282' in error_str:
+            if "GLError" in error_str and "1282" in error_str:
                 # GL context not ready - keep pending image and try again next render
                 # Don't spam the console with repeated messages
-                if not hasattr(self, '_gl_context_warned'):
-                    logger.warning(f"ImageData: GL context error (1282) for {self.image_path}, will retry on next render")
+                if not hasattr(self, "_gl_context_warned"):
+                    logger.warning(
+                        f"ImageData: GL context error (1282) for {self.image_path}, will retry on next render"
+                    )
                     self._gl_context_warned = True
                 return False
             else:
@@ -415,6 +455,7 @@ class ImageData(BaseLayoutElement):
         self._async_loading = False
         self._async_load_requested = False
 
+
 class PlaceholderData(BaseLayoutElement):
     """Class to store placeholder data"""
 
@@ -428,7 +469,7 @@ class PlaceholderData(BaseLayoutElement):
 
         x, y = self.position
         w, h = self.size
-        
+
         # Apply rotation if needed
         if self.rotation != 0:
             glPushMatrix()
@@ -440,7 +481,7 @@ class PlaceholderData(BaseLayoutElement):
             glTranslatef(-w / 2, -h / 2, 0)
             # Now render at origin (rotation pivot is at element center)
             x, y = 0, 0
-        
+
         # Draw a light gray rectangle as placeholder background
         glColor3f(0.9, 0.9, 0.9)  # Light gray
         glBegin(GL_QUADS)
@@ -449,7 +490,7 @@ class PlaceholderData(BaseLayoutElement):
         glVertex2f(x + w, y + h)
         glVertex2f(x, y + h)
         glEnd()
-        
+
         # Draw dashed border for placeholder
         glEnable(GL_LINE_STIPPLE)
         glLineStipple(1, 0x00FF)  # Dashed pattern
@@ -461,7 +502,7 @@ class PlaceholderData(BaseLayoutElement):
         glVertex2f(x, y + h)
         glEnd()
         glDisable(GL_LINE_STIPPLE)
-        
+
         # Pop matrix if we pushed for rotation
         if self.rotation != 0:
             glPopMatrix()
@@ -475,7 +516,7 @@ class PlaceholderData(BaseLayoutElement):
             "rotation": self.rotation,
             "z_index": self.z_index,
             "placeholder_type": self.placeholder_type,
-            "default_content": self.default_content
+            "default_content": self.default_content,
         }
         # Add base fields (v3.0+)
         data.update(self._serialize_base_fields())
@@ -493,6 +534,7 @@ class PlaceholderData(BaseLayoutElement):
         self.placeholder_type = data.get("placeholder_type", "image")
         self.default_content = data.get("default_content", "")
 
+
 class TextBoxData(BaseLayoutElement):
     """Class to store text box data"""
 
@@ -506,7 +548,7 @@ class TextBoxData(BaseLayoutElement):
         """Render the text box using OpenGL"""
         x, y = self.position
         w, h = self.size
-        
+
         # Apply rotation if needed
         if self.rotation != 0:
             glPushMatrix()
@@ -518,11 +560,11 @@ class TextBoxData(BaseLayoutElement):
             glTranslatef(-w / 2, -h / 2, 0)
             # Now render at origin (rotation pivot is at element center)
             x, y = 0, 0
-        
+
         # Enable alpha blending for transparency
         glEnable(GL_BLEND)
         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)
-        
+
         # Draw a semi-transparent yellow rectangle as text box background
         glColor4f(1.0, 1.0, 0.7, 0.3)  # Light yellow with 30% opacity
         glBegin(GL_QUADS)
@@ -531,9 +573,9 @@ class TextBoxData(BaseLayoutElement):
         glVertex2f(x + w, y + h)
         glVertex2f(x, y + h)
         glEnd()
-        
+
         glDisable(GL_BLEND)
-        
+
         # Draw border
         glColor3f(0.0, 0.0, 0.0)  # Black border
         glBegin(GL_LINE_LOOP)
@@ -542,11 +584,11 @@ class TextBoxData(BaseLayoutElement):
         glVertex2f(x + w, y + h)
         glVertex2f(x, y + h)
         glEnd()
-        
+
         # Pop matrix if we pushed for rotation
         if self.rotation != 0:
             glPopMatrix()
-        
+
         # Note: Text content is rendered using QPainter overlay in GLWidget.paintGL()
 
     def serialize(self) -> Dict[str, Any]:
@@ -559,7 +601,7 @@ class TextBoxData(BaseLayoutElement):
             "z_index": self.z_index,
             "text_content": self.text_content,
             "font_settings": self.font_settings,
-            "alignment": self.alignment
+            "alignment": self.alignment,
         }
         # Add base fields (v3.0+)
         data.update(self._serialize_base_fields())
@@ -578,6 +620,7 @@ class TextBoxData(BaseLayoutElement):
         self.font_settings = data.get("font_settings", {"family": "Arial", "size": 12, "color": (0, 0, 0)})
         self.alignment = data.get("alignment", "left")
 
+
 class GhostPageData(BaseLayoutElement):
     """Class to represent a ghost page placeholder for alignment in double-page spreads"""
 
@@ -592,17 +635,17 @@ class GhostPageData(BaseLayoutElement):
         # Render at page origin (0,0) in page-local coordinates
         # PageRenderer will handle transformation to screen coordinates
         x, y = 0, 0
-        
+
         # Calculate dimensions from page_size (in mm) - assume 300 DPI for now
         # This will be overridden by proper size calculation in PageRenderer
         dpi = 300  # Default DPI for rendering
         w = self.page_size[0] * dpi / 25.4
         h = self.page_size[1] * dpi / 25.4
-        
+
         # Enable alpha blending for transparency
         glEnable(GL_BLEND)
         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)
-        
+
         # Draw a light grey semi-transparent rectangle as ghost page background
         glColor4f(0.8, 0.8, 0.8, 0.5)  # Light grey with 50% opacity
         glBegin(GL_QUADS)
@@ -611,9 +654,9 @@ class GhostPageData(BaseLayoutElement):
         glVertex2f(x + w, y + h)
         glVertex2f(x, y + h)
         glEnd()
-        
+
         glDisable(GL_BLEND)
-        
+
         # Draw dashed border
         glEnable(GL_LINE_STIPPLE)
         glLineStipple(2, 0x0F0F)  # Dashed pattern
@@ -625,7 +668,7 @@ class GhostPageData(BaseLayoutElement):
         glVertex2f(x, y + h)
         glEnd()
         glDisable(GL_LINE_STIPPLE)
-        
+
         # Note: "Click to Add Page" text is rendered using QPainter overlay in GLWidget
         # The entire page is clickable
 
@@ -640,12 +683,7 @@ class GhostPageData(BaseLayoutElement):
 
     def serialize(self) -> Dict[str, Any]:
         """Serialize ghost page data to dictionary"""
-        data = {
-            "type": "ghostpage",
-            "position": self.position,
-            "size": self.size,
-            "page_size": self.page_size
-        }
+        data = {"type": "ghostpage", "position": self.position, "size": self.size, "page_size": self.page_size}
         # Add base fields (v3.0+)
         data.update(self._serialize_base_fields())
         return data
diff --git a/pyPhotoAlbum/page_layout.py b/pyPhotoAlbum/page_layout.py
index bc6d2a5..a812f77 100644
--- a/pyPhotoAlbum/page_layout.py
+++ b/pyPhotoAlbum/page_layout.py
@@ -6,19 +6,32 @@ from typing import List, Dict, Any, Optional, Tuple
 from pyPhotoAlbum.models import BaseLayoutElement, ImageData, PlaceholderData, TextBoxData
 from pyPhotoAlbum.snapping import SnappingSystem
 from pyPhotoAlbum.gl_imports import (
-    glBegin, glEnd, glVertex2f, glColor3f, glColor4f,
-    GL_QUADS, GL_LINE_LOOP, GL_LINES, glLineWidth,
-    glEnable, glDisable, GL_DEPTH_TEST, GL_BLEND,
-    glBlendFunc, GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA,
+    glBegin,
+    glEnd,
+    glVertex2f,
+    glColor3f,
+    glColor4f,
+    GL_QUADS,
+    GL_LINE_LOOP,
+    GL_LINES,
+    glLineWidth,
+    glEnable,
+    glDisable,
+    GL_DEPTH_TEST,
+    GL_BLEND,
+    glBlendFunc,
+    GL_SRC_ALPHA,
+    GL_ONE_MINUS_SRC_ALPHA,
 )
 
+
 class PageLayout:
     """Class to manage page layout and templates"""
 
     def __init__(self, width: float = 210, height: float = 297, is_facing_page: bool = False):
         """
         Initialize page layout.
-        
+
         Args:
             width: Width in mm (doubled automatically if is_facing_page=True)
             height: Height in mm
@@ -41,7 +54,7 @@ class PageLayout:
         """Remove a layout element from the page"""
         self.elements.remove(element)
 
-    def set_grid_layout(self, grid: 'GridLayout'):
+    def set_grid_layout(self, grid: "GridLayout"):
         """Set a grid layout for the page"""
         self.grid_layout = grid
 
@@ -58,15 +71,15 @@ class PageLayout:
         """
         # Disable depth testing for 2D rendering
         glDisable(GL_DEPTH_TEST)
-        
+
         # Convert size from mm to pixels based on DPI
         width_px = self.size[0] * dpi / 25.4
         height_px = self.size[1] * dpi / 25.4
-        
+
         # All rendering is at page origin (0, 0) in page-local coordinates
         page_x = 0
         page_y = 0
-        
+
         # Draw drop shadow FIRST (behind everything)
         shadow_offset = 5
         glColor3f(0.5, 0.5, 0.5)
@@ -76,14 +89,14 @@ class PageLayout:
         glVertex2f(page_x + width_px + shadow_offset, page_y + height_px + shadow_offset)
         glVertex2f(page_x + shadow_offset, page_y + height_px + shadow_offset)
         glEnd()
-        
+
         glBegin(GL_QUADS)
         glVertex2f(page_x + width_px, page_y + shadow_offset)
         glVertex2f(page_x + width_px + shadow_offset, page_y + shadow_offset)
         glVertex2f(page_x + width_px + shadow_offset, page_y + height_px)
         glVertex2f(page_x + width_px, page_y + height_px)
         glEnd()
-        
+
         # Draw page background (slightly off-white to distinguish from canvas)
         glColor3f(0.98, 0.98, 0.98)
         glBegin(GL_QUADS)
@@ -97,11 +110,11 @@ class PageLayout:
         # For ImageData elements, request async loading if available
         for element in self.elements:
             # Check if this is an ImageData element that needs async loading
-            if isinstance(element, ImageData) and not hasattr(element, '_texture_id'):
+            if isinstance(element, ImageData) and not hasattr(element, "_texture_id"):
                 # Try to get async loader from a parent widget
-                if hasattr(self, '_async_loader'):
+                if hasattr(self, "_async_loader"):
                     loader = self._async_loader
-                elif hasattr(self, '_parent_widget') and hasattr(self._parent_widget, 'async_image_loader'):
+                elif hasattr(self, "_parent_widget") and hasattr(self._parent_widget, "async_image_loader"):
                     loader = self._parent_widget.async_image_loader
                 else:
                     loader = None
@@ -109,14 +122,15 @@ class PageLayout:
                 # Request async load if loader is available and not already requested
                 if loader and not element._async_load_requested:
                     from pyPhotoAlbum.async_backend import LoadPriority
+
                     # Determine priority based on visibility (HIGH for now, can be refined)
-                    if hasattr(self._parent_widget, 'request_image_load'):
+                    if hasattr(self._parent_widget, "request_image_load"):
                         self._parent_widget.request_image_load(element, priority=LoadPriority.HIGH)
                     element._async_load_requested = True
                     element._async_loading = True
 
             element.render()
-        
+
         # Draw page border LAST (on top of everything)
         glColor3f(0.7, 0.7, 0.7)
         glLineWidth(2.0)
@@ -127,7 +141,7 @@ class PageLayout:
         glVertex2f(page_x, page_y + height_px)
         glEnd()
         glLineWidth(1.0)
-        
+
         # Draw center line for facing pages
         if self.is_facing_page:
             center_x = page_x + (width_px / 2)
@@ -138,13 +152,13 @@ class PageLayout:
             glVertex2f(center_x, page_y + height_px)
             glEnd()
             glLineWidth(1.0)
-        
+
         # Always render snap lines (grid shows when show_grid is on, guides show when show_snap_lines is on)
         self._render_snap_lines(dpi, page_x, page_y, project)
 
         # Re-enable depth testing
         glEnable(GL_DEPTH_TEST)
-    
+
     def _render_snap_lines(self, dpi: int, page_x: float, page_y: float, project=None):
         """Render snap lines (grid, edges, guides)"""
         # Use project settings if available, otherwise fall back to local snapping_system
@@ -169,6 +183,7 @@ class PageLayout:
 
         # Create a temporary snapping system with project settings to get snap lines
         from pyPhotoAlbum.snapping import SnappingSystem
+
         temp_snap_sys = SnappingSystem(snap_threshold_mm=snap_threshold_mm)
         temp_snap_sys.grid_size_mm = grid_size_mm
         temp_snap_sys.snap_to_grid = snap_to_grid
@@ -183,12 +198,12 @@ class PageLayout:
         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)
 
         # Draw grid lines (darker gray with transparency) - visible when show_grid is enabled
-        if show_grid and snap_lines['grid']:
+        if show_grid and snap_lines["grid"]:
             glColor4f(0.6, 0.6, 0.6, 0.4)  # Gray with 40% opacity
             glLineWidth(1.0)
-            for orientation, position in snap_lines['grid']:
+            for orientation, position in snap_lines["grid"]:
                 glBegin(GL_LINES)
-                if orientation == 'vertical':
+                if orientation == "vertical":
                     glVertex2f(page_x + position, page_y)
                     glVertex2f(page_x + position, page_y + self.size[1] * dpi / 25.4)
                 else:  # horizontal
@@ -197,12 +212,12 @@ class PageLayout:
                 glEnd()
 
         # Draw guides (cyan, more visible with transparency) - only show when show_snap_lines is on
-        if show_snap_lines and snap_lines['guides']:
+        if show_snap_lines and snap_lines["guides"]:
             glColor4f(0.0, 0.7, 0.9, 0.8)  # Cyan with 80% opacity
             glLineWidth(1.5)
-            for orientation, position in snap_lines['guides']:
+            for orientation, position in snap_lines["guides"]:
                 glBegin(GL_LINES)
-                if orientation == 'vertical':
+                if orientation == "vertical":
                     glVertex2f(page_x + position, page_y)
                     glVertex2f(page_x + position, page_y + self.size[1] * dpi / 25.4)
                 else:  # horizontal
@@ -223,7 +238,7 @@ class PageLayout:
             "elements": [elem.serialize() for elem in self.elements],
             "grid_layout": self.grid_layout.serialize() if self.grid_layout else None,
             "snapping_system": self.snapping_system.serialize(),
-            "show_snap_lines": self.show_snap_lines
+            "show_snap_lines": self.show_snap_lines,
         }
 
     def deserialize(self, data: Dict[str, Any]):
@@ -250,7 +265,7 @@ class PageLayout:
 
             elem.deserialize(elem_data)
             elem_list.append(elem)
-        
+
         # Sort by z_index to establish proper list order (lower z_index = earlier in list = behind)
         elem_list.sort(key=lambda e: e.z_index)
         self.elements = elem_list
@@ -260,14 +275,15 @@ class PageLayout:
         if grid_data:
             self.grid_layout = GridLayout()
             self.grid_layout.deserialize(grid_data)
-        
+
         # Deserialize snapping system
         snap_data = data.get("snapping_system")
         if snap_data:
             self.snapping_system.deserialize(snap_data)
-        
+
         self.show_snap_lines = data.get("show_snap_lines", True)
 
+
 class GridLayout:
     """Class to manage grid layouts"""
 
@@ -281,7 +297,9 @@ class GridLayout:
         """Merge cells in the grid"""
         self.merged_cells.append((row, col))
 
-    def get_cell_position(self, row: int, col: int, page_width: float = 800, page_height: float = 600) -> Tuple[float, float]:
+    def get_cell_position(
+        self, row: int, col: int, page_width: float = 800, page_height: float = 600
+    ) -> Tuple[float, float]:
         """Get the position of a grid cell"""
         cell_width = (page_width - (self.spacing * (self.columns + 1))) / self.columns
         cell_height = (page_height - (self.spacing * (self.rows + 1))) / self.rows
@@ -300,12 +318,7 @@ class GridLayout:
 
     def serialize(self) -> Dict[str, Any]:
         """Serialize grid layout to dictionary"""
-        return {
-            "rows": self.rows,
-            "columns": self.columns,
-            "spacing": self.spacing,
-            "merged_cells": self.merged_cells
-        }
+        return {"rows": self.rows, "columns": self.columns, "spacing": self.spacing, "merged_cells": self.merged_cells}
 
     def deserialize(self, data: Dict[str, Any]):
         """Deserialize from dictionary"""
diff --git a/pyPhotoAlbum/page_renderer.py b/pyPhotoAlbum/page_renderer.py
index 25fba26..219a85c 100644
--- a/pyPhotoAlbum/page_renderer.py
+++ b/pyPhotoAlbum/page_renderer.py
@@ -17,21 +17,17 @@ from pyPhotoAlbum.gl_imports import glPushMatrix, glPopMatrix, glScalef, glTrans
 class PageRenderer:
     """
     Handles rendering and coordinate transformations for a single page.
-    
+
     This class encapsulates all coordinate transformations needed to render
     a page and its elements consistently.
     """
-    
-    def __init__(self, 
-                 page_width_mm: float, 
-                 page_height_mm: float,
-                 screen_x: float,
-                 screen_y: float,
-                 dpi: int,
-                 zoom: float):
+
+    def __init__(
+        self, page_width_mm: float, page_height_mm: float, screen_x: float, screen_y: float, dpi: int, zoom: float
+    ):
         """
         Initialize a page renderer.
-        
+
         Args:
             page_width_mm: Page width in millimeters
             page_height_mm: Page height in millimeters
@@ -46,81 +42,83 @@ class PageRenderer:
         self.screen_y = screen_y
         self.dpi = dpi
         self.zoom = zoom
-        
+
         # Calculate page dimensions in pixels
         self.page_width_px = page_width_mm * dpi / 25.4
         self.page_height_px = page_height_mm * dpi / 25.4
-        
+
         # Calculate screen dimensions (with zoom applied)
         self.screen_width = self.page_width_px * zoom
         self.screen_height = self.page_height_px * zoom
-    
+
     def page_to_screen(self, page_x: float, page_y: float) -> Tuple[float, float]:
         """
         Convert page-local coordinates (in pixels) to screen coordinates.
-        
+
         Args:
             page_x: X coordinate in page-local space (pixels)
             page_y: Y coordinate in page-local space (pixels)
-            
+
         Returns:
             Tuple of (screen_x, screen_y)
         """
         screen_x = self.screen_x + page_x * self.zoom
         screen_y = self.screen_y + page_y * self.zoom
         return (screen_x, screen_y)
-    
+
     def screen_to_page(self, screen_x: float, screen_y: float) -> Tuple[float, float]:
         """
         Convert screen coordinates to page-local coordinates (in pixels).
-        
+
         Args:
             screen_x: X coordinate in screen space
             screen_y: Y coordinate in screen space
-            
+
         Returns:
             Tuple of (page_x, page_y) in pixels, or None if outside page bounds
         """
         page_x = (screen_x - self.screen_x) / self.zoom
         page_y = (screen_y - self.screen_y) / self.zoom
         return (page_x, page_y)
-    
+
     def is_point_in_page(self, screen_x: float, screen_y: float) -> bool:
         """
         Check if a screen coordinate is within the page bounds.
-        
+
         Args:
             screen_x: X coordinate in screen space
             screen_y: Y coordinate in screen space
-            
+
         Returns:
             True if the point is within the page bounds
         """
-        return (self.screen_x <= screen_x <= self.screen_x + self.screen_width and
-                self.screen_y <= screen_y <= self.screen_y + self.screen_height)
-    
+        return (
+            self.screen_x <= screen_x <= self.screen_x + self.screen_width
+            and self.screen_y <= screen_y <= self.screen_y + self.screen_height
+        )
+
     def get_sub_page_at(self, screen_x: float, is_facing_page: bool) -> Optional[str]:
         """
         For facing page spreads, determine if mouse is on left or right page.
-        
+
         Args:
             screen_x: X coordinate in screen space
             is_facing_page: Whether this is a facing page spread
-            
+
         Returns:
             'left' or 'right' for facing pages, None for single pages
         """
         if not is_facing_page:
             return None
-        
+
         # Calculate the center line of the spread
         center_x = self.screen_x + self.screen_width / 2
-        
+
         if screen_x < center_x:
-            return 'left'
+            return "left"
         else:
-            return 'right'
-    
+            return "right"
+
     def begin_render(self):
         """
         Set up OpenGL transformations for rendering this page.
@@ -131,27 +129,27 @@ class PageRenderer:
         glScalef(self.zoom, self.zoom, 1.0)
         # Translate to page position (in zoomed coordinates)
         glTranslatef(self.screen_x / self.zoom, self.screen_y / self.zoom, 0.0)
-    
+
     def end_render(self):
         """
         Clean up OpenGL transformations after rendering this page.
         Call this after rendering page content.
         """
         glPopMatrix()
-    
+
     def get_page_bounds_screen(self) -> Tuple[float, float, float, float]:
         """
         Get the page bounds in screen coordinates.
-        
+
         Returns:
             Tuple of (x, y, width, height) in screen space
         """
         return (self.screen_x, self.screen_y, self.screen_width, self.screen_height)
-    
+
     def get_page_bounds_page(self) -> Tuple[float, float, float, float]:
         """
         Get the page bounds in page-local coordinates.
-        
+
         Returns:
             Tuple of (x, y, width, height) in page-local space (pixels)
         """
diff --git a/pyPhotoAlbum/pdf_exporter.py b/pyPhotoAlbum/pdf_exporter.py
index 64b6855..c8f9c4f 100644
--- a/pyPhotoAlbum/pdf_exporter.py
+++ b/pyPhotoAlbum/pdf_exporter.py
@@ -25,6 +25,7 @@ from pyPhotoAlbum.image_utils import (
 @dataclass
 class RenderContext:
     """Parameters for rendering an image element"""
+
     canvas: canvas.Canvas
     image_element: ImageData
     x_pt: float
@@ -41,6 +42,7 @@ class RenderContext:
 @dataclass
 class SplitRenderParams:
     """Parameters for rendering a split element"""
+
     canvas: canvas.Canvas
     element: any
     x_offset_mm: float
@@ -53,15 +55,15 @@ class SplitRenderParams:
 
 class PDFExporter:
     """Handles PDF export of photo album projects"""
-    
+
     # Conversion constants
     MM_TO_POINTS = 2.834645669  # 1mm = 2.834645669 points
     SPLIT_THRESHOLD_RATIO = 0.002  # 1:500 threshold for tiny elements
-    
+
     def __init__(self, project, export_dpi: int = 300):
         """
         Initialize PDF exporter with a project.
-        
+
         Args:
             project: The Project instance to export
             export_dpi: Target DPI for images in the PDF (default 300 for print quality)
@@ -71,48 +73,46 @@ class PDFExporter:
         self.export_dpi = export_dpi
         self.warnings = []
         self.current_pdf_page = 1
-        
+
     def export(self, output_path: str, progress_callback=None) -> Tuple[bool, List[str]]:
         """
         Export the project to PDF.
-        
+
         Args:
             output_path: Path where PDF should be saved
             progress_callback: Optional callback(current, total, message) for progress updates
-            
+
         Returns:
             Tuple of (success: bool, warnings: List[str])
         """
         self.warnings = []
         self.current_pdf_page = 1
-        
+
         try:
             # Calculate total pages for progress (cover counts as 1)
             total_pages = sum(
-                1 if page.is_cover else (2 if page.is_double_spread else 1) 
-                for page in self.project.pages
+                1 if page.is_cover else (2 if page.is_double_spread else 1) for page in self.project.pages
             )
-            
+
             # Get page dimensions from project (in mm)
             page_width_mm, page_height_mm = self.project.page_size_mm
-            
+
             # Convert to PDF points
             page_width_pt = page_width_mm * self.MM_TO_POINTS
             page_height_pt = page_height_mm * self.MM_TO_POINTS
-            
+
             # Create PDF canvas
             c = canvas.Canvas(output_path, pagesize=(page_width_pt, page_height_pt))
-            
+
             # Process each page
             pages_processed = 0
             for page in self.project.pages:
                 # Get display name for progress
                 page_name = self.project.get_page_display_name(page)
-                
+
                 if progress_callback:
-                    progress_callback(pages_processed, total_pages, 
-                                    f"Exporting {page_name}...")
-                
+                    progress_callback(pages_processed, total_pages, f"Exporting {page_name}...")
+
                 if page.is_cover:
                     # Export cover as single page with wrap-around design
                     self._export_cover(c, page, page_width_pt, page_height_pt)
@@ -124,9 +124,8 @@ class PDFExporter:
                         c.showPage()  # Finish current page
                         self.current_pdf_page += 1
                         if progress_callback:
-                            progress_callback(pages_processed, total_pages, 
-                                            f"Inserting blank page for alignment...")
-                    
+                            progress_callback(pages_processed, total_pages, f"Inserting blank page for alignment...")
+
                     # Export spread as two pages
                     self._export_spread(c, page, page_width_pt, page_height_pt)
                     pages_processed += 2
@@ -134,112 +133,109 @@ class PDFExporter:
                     # Export single page
                     self._export_single_page(c, page, page_width_pt, page_height_pt)
                     pages_processed += 1
-            
+
             # Save PDF
             c.save()
-            
+
             if progress_callback:
                 progress_callback(total_pages, total_pages, "Export complete!")
-            
+
             return True, self.warnings
-            
+
         except Exception as e:
             self.warnings.append(f"Export failed: {str(e)}")
             return False, self.warnings
-    
-    def _export_cover(self, c: canvas.Canvas, page, page_width_pt: float, 
-                     page_height_pt: float):
+
+    def _export_cover(self, c: canvas.Canvas, page, page_width_pt: float, page_height_pt: float):
         """
         Export a cover page to PDF.
         Cover has different dimensions (wrap-around: front + spine + back + bleed).
         """
         # Get cover dimensions (already calculated in page.layout.size)
         cover_width_mm, cover_height_mm = page.layout.size
-        
+
         # Convert to PDF points
         cover_width_pt = cover_width_mm * self.MM_TO_POINTS
         cover_height_pt = cover_height_mm * self.MM_TO_POINTS
-        
+
         # Create a new page with cover dimensions
         c.setPageSize((cover_width_pt, cover_height_pt))
-        
+
         # Render all elements on the cover
         for element in sorted(page.layout.elements, key=lambda x: x.z_index):
             self._render_element(c, element, 0, cover_width_pt, cover_height_pt, "Cover")
-        
+
         # Draw guide lines for front/spine/back zones
         self._draw_cover_guides(c, cover_width_pt, cover_height_pt)
-        
+
         c.showPage()  # Finish cover page
         self.current_pdf_page += 1
-        
+
         # Reset page size for content pages
         c.setPageSize((page_width_pt, page_height_pt))
-    
+
     def _draw_cover_guides(self, c: canvas.Canvas, cover_width_pt: float, cover_height_pt: float):
         """Draw guide lines for cover zones (front/spine/back)"""
         from reportlab.lib.colors import lightgrey
-        
+
         # Calculate zone boundaries
         bleed_pt = self.project.cover_bleed_mm * self.MM_TO_POINTS
         page_width_pt = self.project.page_size_mm[0] * self.MM_TO_POINTS
         spine_width_pt = self.project.calculate_spine_width() * self.MM_TO_POINTS
-        
+
         # Zone boundaries (from left to right)
         # Bleed | Back | Spine | Front | Bleed
         back_start = bleed_pt
         spine_start = bleed_pt + page_width_pt
         front_start = bleed_pt + page_width_pt + spine_width_pt
         front_end = bleed_pt + page_width_pt + spine_width_pt + page_width_pt
-        
+
         # Draw dashed lines at zone boundaries
         c.saveState()
         c.setStrokeColor(lightgrey)
         c.setDash(3, 3)
         c.setLineWidth(0.5)
-        
+
         # Back/Spine boundary
         c.line(spine_start, 0, spine_start, cover_height_pt)
-        
+
         # Spine/Front boundary
         c.line(front_start, 0, front_start, cover_height_pt)
-        
+
         # Bleed boundaries (outer edges)
         if bleed_pt > 0:
             c.line(back_start, 0, back_start, cover_height_pt)
             c.line(front_end, 0, front_end, cover_height_pt)
-        
+
         c.restoreState()
-    
-    def _export_single_page(self, c: canvas.Canvas, page, page_width_pt: float, 
-                           page_height_pt: float):
+
+    def _export_single_page(self, c: canvas.Canvas, page, page_width_pt: float, page_height_pt: float):
         """Export a single page to PDF"""
         # Render all elements
         for element in sorted(page.layout.elements, key=lambda x: x.z_index):
             self._render_element(c, element, 0, page_width_pt, page_height_pt, page.page_number)
-        
+
         c.showPage()  # Finish this page
         self.current_pdf_page += 1
-    
-    def _export_spread(self, c: canvas.Canvas, page, page_width_pt: float, 
-                      page_height_pt: float):
+
+    def _export_spread(self, c: canvas.Canvas, page, page_width_pt: float, page_height_pt: float):
         """Export a double-page spread as two PDF pages"""
         # Get center line position in mm
         page_width_mm = self.project.page_size_mm[0]
         center_mm = page_width_mm  # Center of the spread (which is 2x width)
-        
+
         # Convert center line to pixels for comparison
         dpi = self.project.working_dpi
         center_px = center_mm * dpi / 25.4
-        
+
         # Calculate threshold for tiny elements (1:500) in pixels
         threshold_px = page_width_mm * self.SPLIT_THRESHOLD_RATIO * dpi / 25.4
-        
+
         # Process elements for left page
         for element in sorted(page.layout.elements, key=lambda x: x.z_index):
             element_x_px, element_y_px = element.position
             element_width_px, element_height_px = element.size
-            
+
             # Check if element is on left page, right page, or spanning (compare in pixels)
             if element_x_px + element_width_px <= center_px + threshold_px:
                 # Entirely on left page
@@ -257,23 +253,22 @@ class PDFExporter:
                     page_width_pt=page_width_pt,
                     page_height_pt=page_height_pt,
                     page_number=page.page_number,
-                    side='left'
+                    side="left",
                 )
                 self._render_split_element(params)
-        
+
         c.showPage()  # Finish left page
         self.current_pdf_page += 1
-        
+
         # Process elements for right page
         for element in sorted(page.layout.elements, key=lambda x: x.z_index):
             element_x_px, element_y_px = element.position
             element_width_px, element_height_px = element.size
-            
+
             # Check if element is on right page or spanning (compare in pixels)
             if element_x_px >= center_px - threshold_px and element_x_px + element_width_px > center_px:
                 # Entirely on right page or mostly on right
-                self._render_element(c, element, center_mm, page_width_pt, page_height_pt, 
-                                   page.page_number + 1)
+                self._render_element(c, element, center_mm, page_width_pt, page_height_pt, page.page_number + 1)
             elif element_x_px < center_px and element_x_px + element_width_px > center_px + threshold_px:
                 # Spanning element - render right portion
                 params = SplitRenderParams(
@@ -284,18 +279,25 @@ class PDFExporter:
                     page_width_pt=page_width_pt,
                     page_height_pt=page_height_pt,
                     page_number=page.page_number + 1,
-                    side='right'
+                    side="right",
                 )
                 self._render_split_element(params)
-        
+
         c.showPage()  # Finish right page
         self.current_pdf_page += 1
-    
-    def _render_element(self, c: canvas.Canvas, element, x_offset_mm: float, 
-                       page_width_pt: float, page_height_pt: float, page_number: int):
+
+    def _render_element(
+        self,
+        c: canvas.Canvas,
+        element,
+        x_offset_mm: float,
+        page_width_pt: float,
+        page_height_pt: float,
+        page_number: int,
+    ):
         """
         Render a single element on the PDF canvas.
-        
+
         Args:
             c: ReportLab canvas
             element: The layout element to render
@@ -307,27 +309,27 @@ class PDFExporter:
         # Skip placeholders
         if isinstance(element, PlaceholderData):
             return
-        
+
         # Get element position and size (in PIXELS from OpenGL coordinates)
         element_x_px, element_y_px = element.position
         element_width_px, element_height_px = element.size
-        
+
         # Convert from pixels to mm using the working DPI
         dpi = self.project.working_dpi
         element_x_mm = element_x_px * 25.4 / dpi
         element_y_mm = element_y_px * 25.4 / dpi
         element_width_mm = element_width_px * 25.4 / dpi
         element_height_mm = element_height_px * 25.4 / dpi
-        
+
         # Adjust x position for offset (now in mm)
         adjusted_x_mm = element_x_mm - x_offset_mm
-        
+
         # Convert to PDF points and flip Y coordinate (PDF origin is bottom-left)
         x_pt = adjusted_x_mm * self.MM_TO_POINTS
         y_pt = page_height_pt - (element_y_mm * self.MM_TO_POINTS) - (element_height_mm * self.MM_TO_POINTS)
         width_pt = element_width_mm * self.MM_TO_POINTS
         height_pt = element_height_mm * self.MM_TO_POINTS
-        
+
         if isinstance(element, ImageData):
             ctx = RenderContext(
                 canvas=c,
@@ -336,12 +338,12 @@ class PDFExporter:
                 y_pt=y_pt,
                 width_pt=width_pt,
                 height_pt=height_pt,
-                page_number=page_number
+                page_number=page_number,
             )
             self._render_image(ctx)
         elif isinstance(element, TextBoxData):
             self._render_textbox(c, element, x_pt, y_pt, width_pt, height_pt)
-    
+
     def _render_split_element(self, params: SplitRenderParams):
         """
         Render a split element (only the portion on one side of the split line).
@@ -352,7 +354,7 @@ class PDFExporter:
         # Skip placeholders
         if isinstance(params.element, PlaceholderData):
             return
-        
+
         # Get element position and size in pixels
         element_x_px, element_y_px = params.element.position
         element_width_px, element_height_px = params.element.size
@@ -366,7 +368,7 @@ class PDFExporter:
 
         if isinstance(params.element, ImageData):
             # Calculate which portion of the image to render
-            if params.side == 'left':
+            if params.side == "left":
                 # Render from element start to split line
                 crop_width_mm = params.split_line_mm - element_x_mm
                 crop_x_start = 0
@@ -402,7 +404,7 @@ class PDFExporter:
                 crop_left=crop_x_start / element_width_mm,
                 crop_right=(crop_x_start + crop_width_mm) / element_width_mm,
                 original_width_pt=original_width_pt,
-                original_height_pt=original_height_pt
+                original_height_pt=original_height_pt,
             )
             self._render_image(ctx)
 
@@ -410,11 +412,18 @@ class PDFExporter:
             # For text boxes spanning the split, we'll render the whole text on the side
             # where most of it appears (simpler than trying to split text)
             element_center_mm = element_x_mm + element_width_mm / 2
-            if (params.side == 'left' and element_center_mm < params.split_line_mm) or \
-               (params.side == 'right' and element_center_mm >= params.split_line_mm):
-                self._render_element(params.canvas, params.element, params.x_offset_mm,
-                                   params.page_width_pt, params.page_height_pt, params.page_number)
-    
+            if (params.side == "left" and element_center_mm < params.split_line_mm) or (
+                params.side == "right" and element_center_mm >= params.split_line_mm
+            ):
+                self._render_element(
+                    params.canvas,
+                    params.element,
+                    params.x_offset_mm,
+                    params.page_width_pt,
+                    params.page_height_pt,
+                    params.page_number,
+                )
+
     def _render_image(self, ctx: RenderContext):
         """
         Render an image element on the PDF canvas.
@@ -438,7 +447,7 @@ class PDFExporter:
             img = convert_to_rgba(img)
 
             # Apply PIL-level rotation if needed
-            if hasattr(ctx.image_element, 'pil_rotation_90') and ctx.image_element.pil_rotation_90 > 0:
+            if hasattr(ctx.image_element, "pil_rotation_90") and ctx.image_element.pil_rotation_90 > 0:
                 img = apply_pil_rotation(img, ctx.image_element.pil_rotation_90)
 
             # Get element's crop_info and combine with split cropping if applicable
@@ -458,27 +467,28 @@ class PDFExporter:
             # Calculate center crop coordinates
             img_width, img_height = img.size
             crop_coords = calculate_center_crop_coords(
-                img_width, img_height,
-                target_width, target_height,
-                (final_crop_x_min, crop_y_min, final_crop_x_max, crop_y_max)
+                img_width,
+                img_height,
+                target_width,
+                target_height,
+                (final_crop_x_min, crop_y_min, final_crop_x_max, crop_y_max),
             )
 
             # Crop the image
             cropped_img = crop_image_to_coords(img, crop_coords)
-            
+
             # Downsample image to target resolution based on export DPI
             # This prevents embedding huge images and reduces PDF file size
             # Calculate target dimensions in pixels based on physical size and export DPI
             target_width_px = int((ctx.width_pt / self.MM_TO_POINTS) * self.export_dpi / 25.4)
             target_height_px = int((ctx.height_pt / self.MM_TO_POINTS) * self.export_dpi / 25.4)
-            
+
             # Only downsample if current image is larger than target
             # Don't upscale small images as that would reduce quality
             current_width, current_height = cropped_img.size
             if current_width > target_width_px or current_height > target_height_px:
                 # Use LANCZOS resampling for high quality downsampling
-                cropped_img = cropped_img.resize((target_width_px, target_height_px),
-                                                Image.Resampling.LANCZOS)
+                cropped_img = cropped_img.resize((target_width_px, target_height_px), Image.Resampling.LANCZOS)
 
             # Note: Rotation is applied at the canvas level (below), not here
             # to avoid double-rotation issues
@@ -495,12 +505,20 @@ class PDFExporter:
                 ctx.canvas.rotate(-ctx.image_element.rotation)
                 ctx.canvas.translate(-ctx.width_pt / 2, -ctx.height_pt / 2)
                 # Draw at origin after transformation
-                ctx.canvas.drawImage(ImageReader(cropped_img), 0, 0, ctx.width_pt, ctx.height_pt,
-                          mask='auto', preserveAspectRatio=False)
+                ctx.canvas.drawImage(
+                    ImageReader(cropped_img), 0, 0, ctx.width_pt, ctx.height_pt, mask="auto", preserveAspectRatio=False
+                )
             else:
                 # Draw without rotation
-                ctx.canvas.drawImage(ImageReader(cropped_img), ctx.x_pt, ctx.y_pt, ctx.width_pt, ctx.height_pt,
-                          mask='auto', preserveAspectRatio=False)
+                ctx.canvas.drawImage(
+                    ImageReader(cropped_img),
+                    ctx.x_pt,
+                    ctx.y_pt,
+                    ctx.width_pt,
+                    ctx.height_pt,
+                    mask="auto",
+                    preserveAspectRatio=False,
+                )
 
             ctx.canvas.restoreState()
 
@@ -508,9 +526,10 @@ class PDFExporter:
             warning = f"Page {ctx.page_number}: Error rendering image {ctx.image_element.image_path}: {str(e)}"
             print(f"WARNING: {warning}")
             self.warnings.append(warning)
-    
-    def _render_textbox(self, c: canvas.Canvas, text_element: 'TextBoxData',
-                       x_pt: float, y_pt: float, width_pt: float, height_pt: float):
+
+    def _render_textbox(
+        self, c: canvas.Canvas, text_element: "TextBoxData", x_pt: float, y_pt: float, width_pt: float, height_pt: float
+    ):
         """
         Render a text box element on the PDF canvas with transparent background.
         Text is word-wrapped to fit within the box boundaries.
@@ -524,9 +543,9 @@ class PDFExporter:
             return
 
         # Get font settings
-        font_family = text_element.font_settings.get('family', 'Helvetica')
-        font_size_px = text_element.font_settings.get('size', 12)
-        font_color = text_element.font_settings.get('color', (0, 0, 0))
+        font_family = text_element.font_settings.get("family", "Helvetica")
+        font_size_px = text_element.font_settings.get("size", 12)
+        font_color = text_element.font_settings.get("color", (0, 0, 0))
 
         # Convert font size from pixels to PDF points (same conversion as element dimensions)
         # Font size is stored in pixels at working_dpi, same as element position/size
@@ -536,34 +555,32 @@ class PDFExporter:
 
         # Map common font names to ReportLab standard fonts
         font_map = {
-            'Arial': 'Helvetica',
-            'Times New Roman': 'Times-Roman',
-            'Courier New': 'Courier',
+            "Arial": "Helvetica",
+            "Times New Roman": "Times-Roman",
+            "Courier New": "Courier",
         }
         font_family = font_map.get(font_family, font_family)
 
         # Normalize color to hex for Paragraph style
         if all(isinstance(x, int) and x > 1 for x in font_color):
-            color_hex = '#{:02x}{:02x}{:02x}'.format(*font_color)
+            color_hex = "#{:02x}{:02x}{:02x}".format(*font_color)
         else:
             # Convert 0-1 range to 0-255 then to hex
-            color_hex = '#{:02x}{:02x}{:02x}'.format(
-                int(font_color[0] * 255),
-                int(font_color[1] * 255),
-                int(font_color[2] * 255)
+            color_hex = "#{:02x}{:02x}{:02x}".format(
+                int(font_color[0] * 255), int(font_color[1] * 255), int(font_color[2] * 255)
             )
 
         # Map alignment to ReportLab constants
         alignment_map = {
-            'left': TA_LEFT,
-            'center': TA_CENTER,
-            'right': TA_RIGHT,
+            "left": TA_LEFT,
+            "center": TA_CENTER,
+            "right": TA_RIGHT,
         }
         text_alignment = alignment_map.get(text_element.alignment, TA_LEFT)
 
         # Create paragraph style with word wrapping
         style = ParagraphStyle(
-            'textbox',
+            "textbox",
             fontName=font_family,
             fontSize=font_size,
             leading=font_size * 1.2,  # Line spacing (120% of font size)
@@ -573,10 +590,10 @@ class PDFExporter:
 
         # Escape special XML characters and convert newlines to <br/> tags
         text_content = text_element.text_content
-        text_content = text_content.replace('&', '&amp;')
-        text_content = text_content.replace('<', '&lt;')
-        text_content = text_content.replace('>', '&gt;')
-        text_content = text_content.replace('\n', '<br/>')
+        text_content = text_content.replace("&", "&amp;")
+        text_content = text_content.replace("<", "&lt;")
+        text_content = text_content.replace(">", "&gt;")
+        text_content = text_content.replace("\n", "<br/>")
 
         # Create paragraph with the text
         para = Paragraph(text_content, style)
diff --git a/pyPhotoAlbum/project.py b/pyPhotoAlbum/project.py
index e8938b0..719479b 100644
--- a/pyPhotoAlbum/project.py
+++ b/pyPhotoAlbum/project.py
@@ -11,6 +11,7 @@ from pyPhotoAlbum.page_layout import PageLayout
 from pyPhotoAlbum.commands import CommandHistory
 from pyPhotoAlbum.asset_manager import AssetManager
 
+
 class Page:
     """Class representing a single page in the photo album"""
 
@@ -39,7 +40,7 @@ class Page:
         # Deletion tracking for merge (v3.0+)
         self.deleted = False
         self.deleted_at: Optional[str] = None
-        
+
         # Create layout with appropriate width
         if layout is None:
             self.layout = PageLayout(is_facing_page=is_double_spread)
@@ -51,21 +52,21 @@ class Page:
                 self.layout.is_facing_page = is_double_spread
                 height = self.layout.size[1]
                 # Use the base_width if available, otherwise derive it
-                if hasattr(self.layout, 'base_width'):
+                if hasattr(self.layout, "base_width"):
                     base_width = self.layout.base_width
                 else:
                     # If base_width not set, assume current width is correct
                     # and derive base_width from current state
                     base_width = self.layout.size[0] / 2 if not is_double_spread else self.layout.size[0]
                     self.layout.base_width = base_width
-                
+
                 # Set the new width based on facing page state
                 self.layout.size = (base_width * 2 if is_double_spread else base_width, height)
-    
+
     def get_page_numbers(self) -> List[int]:
         """
         Get the page numbers this page represents.
-        
+
         Returns:
             List of page numbers (2 numbers for spreads, 1 for single pages)
         """
@@ -73,7 +74,7 @@ class Page:
             return [self.page_number, self.page_number + 1]
         else:
             return [self.page_number]
-    
+
     def get_page_count(self) -> int:
         """
         Get the number of physical pages this represents.
@@ -133,6 +134,7 @@ class Page:
         self.layout = PageLayout()
         self.layout.deserialize(layout_data)
 
+
 class Project:
     """Class representing the entire photo album project"""
 
@@ -230,37 +232,33 @@ class Project:
         if self.has_cover and self.pages:
             self.update_cover_dimensions()
         self.mark_dirty()
-    
+
     def calculate_spine_width(self) -> float:
         """
         Calculate spine width based on page count and paper thickness.
-        
+
         For saddle stitch binding:
         - Each sheet = 4 pages (2 pages per side when folded)
         - Spine width = (Number of sheets × Paper thickness × 2)
-        
+
         Returns:
             Spine width in mm
         """
         if not self.has_cover:
             return 0.0
-        
+
         # Count content pages (excluding cover)
-        content_page_count = sum(
-            page.get_page_count() 
-            for page in self.pages 
-            if not page.is_cover
-        )
-        
+        content_page_count = sum(page.get_page_count() for page in self.pages if not page.is_cover)
+
         if self.binding_type == "saddle_stitch":
             # Calculate number of sheets (each sheet = 4 pages)
             sheets = math.ceil(content_page_count / 4)
             # Spine width = sheets × paper thickness × 2 (folded)
             spine_width = sheets * self.paper_thickness_mm * 2
             return spine_width
-        
+
         return 0.0
-    
+
     def update_cover_dimensions(self):
         """
         Update cover page dimensions based on current page count and settings.
@@ -268,66 +266,68 @@ class Project:
         """
         if not self.has_cover or not self.pages:
             return
-        
+
         # Find cover page (should be first page)
         cover_page = None
         for page in self.pages:
             if page.is_cover:
                 cover_page = page
                 break
-        
+
         if not cover_page:
             return
-        
+
         # Get standard page dimensions
         page_width_mm, page_height_mm = self.page_size_mm
-        
+
         # Calculate spine width
         spine_width = self.calculate_spine_width()
-        
+
         # Calculate cover dimensions
         # Cover = Front + Spine + Back + Bleed on all sides
         cover_width = (page_width_mm * 2) + spine_width + (self.cover_bleed_mm * 2)
         cover_height = page_height_mm + (self.cover_bleed_mm * 2)
-        
+
         # Update cover page layout
         cover_page.layout.size = (cover_width, cover_height)
         cover_page.layout.base_width = page_width_mm  # Store base width for reference
         cover_page.manually_sized = True  # Mark as manually sized
-        
-        print(f"Cover dimensions updated: {cover_width:.1f} × {cover_height:.1f} mm "
-              f"(Front: {page_width_mm}, Spine: {spine_width:.2f}, Back: {page_width_mm}, "
-              f"Bleed: {self.cover_bleed_mm})")
-    
+
+        print(
+            f"Cover dimensions updated: {cover_width:.1f} × {cover_height:.1f} mm "
+            f"(Front: {page_width_mm}, Spine: {spine_width:.2f}, Back: {page_width_mm}, "
+            f"Bleed: {self.cover_bleed_mm})"
+        )
+
     def get_page_display_name(self, page: Page) -> str:
         """
         Get display name for a page.
-        
+
         Args:
             page: The page to get the display name for
-            
+
         Returns:
             Display name like "Cover", "Page 1", "Pages 1-2", etc.
         """
         if page.is_cover:
             return "Cover"
-        
+
         # Calculate adjusted page number (excluding cover from count)
         adjusted_num = page.page_number
         if self.has_cover:
             # Subtract 1 to account for cover
             adjusted_num = page.page_number - 1
-        
+
         if page.is_double_spread:
             return f"Pages {adjusted_num}-{adjusted_num + 1}"
         else:
             return f"Page {adjusted_num}"
-    
+
     def calculate_page_layout_with_ghosts(self) -> List[Tuple[str, Any, int]]:
         """
         Calculate page layout including ghost pages for alignment.
         Excludes cover from spread calculations.
-        
+
         Returns:
             List of tuples (page_type, page_or_ghost, logical_position)
             where page_type is 'page' or 'ghost',
@@ -335,10 +335,10 @@ class Project:
             logical_position is the position in the album (1=right, 2=left, etc.)
         """
         from pyPhotoAlbum.models import GhostPageData
-        
+
         layout = []
         current_position = 1  # Start at position 1 (right page)
-        
+
         for page in self.pages:
             # Skip cover in spread calculations
             if page.is_cover:
@@ -354,32 +354,32 @@ class Project:
             elif not page.is_double_spread and current_position % 2 == 1:
                 # Current position is odd (right page), single page is fine
                 pass
-            
+
             # Actually, let me reconsider the logic:
             # In a photobook:
             # - Position 1 is the right page (when opened, first content page)
             # - Position 2 is the left page of the next spread
             # - Position 3 is the right page of the next spread
             # - etc.
-            # 
+            #
             # Double spreads occupy TWO positions (both left and right of a spread)
             # They must start on an even position (left side) so they span across both pages
-            
+
             # Check if this is a double spread starting at an odd position
             if page.is_double_spread and current_position % 2 == 1:
                 # Need to insert a ghost page to push the double spread to next position
-                layout.append(('ghost', None, current_position))
+                layout.append(("ghost", None, current_position))
                 current_position += 1
-            
+
             # Add the actual page
-            layout.append(('page', page, current_position))
-            
+            layout.append(("page", page, current_position))
+
             # Update position based on page type
             if page.is_double_spread:
                 current_position += 2  # Double spread takes 2 positions
             else:
                 current_position += 1  # Single page takes 1 position
-        
+
         return layout
 
     def render_all_pages(self):
@@ -453,7 +453,7 @@ class Project:
         now = datetime.now(timezone.utc).isoformat()
         self.created = data.get("created", now)
         self.last_modified = data.get("last_modified", now)
-        
+
         self.pages = []
 
         # Deserialize asset manager
@@ -461,13 +461,13 @@ class Project:
         asset_data = data.get("asset_manager")
         if asset_data:
             self.asset_manager.deserialize(asset_data)
-        
+
         # Deserialize pages
         for page_data in data.get("pages", []):
             page = Page()
             page.deserialize(page_data)
             self.pages.append(page)
-        
+
         # Deserialize command history with asset manager and project reference
         history_data = data.get("history")
         if history_data:
diff --git a/pyPhotoAlbum/project_serializer.py b/pyPhotoAlbum/project_serializer.py
index ef9873e..d4066a1 100644
--- a/pyPhotoAlbum/project_serializer.py
+++ b/pyPhotoAlbum/project_serializer.py
@@ -14,7 +14,7 @@ from pyPhotoAlbum.version_manager import (
     CURRENT_DATA_VERSION,
     check_version_compatibility,
     VersionCompatibility,
-    DataMigration
+    DataMigration,
 )
 
 
@@ -44,7 +44,7 @@ def _import_external_images(project: Project):
                     # Absolute path - definitely external
                     is_external = True
                     external_path = element.image_path
-                elif not element.image_path.startswith('assets/'):
+                elif not element.image_path.startswith("assets/"):
                     # Relative path but not in assets folder
                     # Check if it exists relative to project folder
                     full_path = os.path.join(project.folder_path, element.image_path)
@@ -91,15 +91,15 @@ def _normalize_asset_paths(project: Project, project_folder: str):
                 original_path = element.image_path
 
                 # Skip if already a simple relative path (assets/...)
-                if not os.path.isabs(original_path) and not original_path.startswith('./projects/'):
+                if not os.path.isabs(original_path) and not original_path.startswith("./projects/"):
                     continue
 
                 # Try to extract just the filename or relative path from assets folder
                 # Pattern 1: "./projects/XXX/assets/filename.jpg" -> "assets/filename.jpg"
-                if '/assets/' in original_path:
-                    parts = original_path.split('/assets/')
+                if "/assets/" in original_path:
+                    parts = original_path.split("/assets/")
                     if len(parts) == 2:
-                        new_path = os.path.join('assets', parts[1])
+                        new_path = os.path.join("assets", parts[1])
                         element.image_path = new_path
                         normalized_count += 1
                         print(f"Normalized path: {original_path} -> {new_path}")
@@ -133,8 +133,8 @@ def save_to_zip(project: Project, zip_path: str) -> Tuple[bool, Optional[str]]:
     """
     try:
         # Ensure .ppz extension
-        if not zip_path.lower().endswith('.ppz'):
-            zip_path += '.ppz'
+        if not zip_path.lower().endswith(".ppz"):
+            zip_path += ".ppz"
 
         # Check for and import any external images before saving
         _import_external_images(project)
@@ -143,14 +143,14 @@ def save_to_zip(project: Project, zip_path: str) -> Tuple[bool, Optional[str]]:
         project_data = project.serialize()
 
         # Add version information
-        project_data['serialization_version'] = SERIALIZATION_VERSION  # Legacy field
-        project_data['data_version'] = CURRENT_DATA_VERSION  # New versioning system
+        project_data["serialization_version"] = SERIALIZATION_VERSION  # Legacy field
+        project_data["data_version"] = CURRENT_DATA_VERSION  # New versioning system
 
         # Create ZIP file
-        with zipfile.ZipFile(zip_path, 'w', zipfile.ZIP_DEFLATED) as zipf:
+        with zipfile.ZipFile(zip_path, "w", zipfile.ZIP_DEFLATED) as zipf:
             # Write project.json with stable sorting for git-friendly diffs
             project_json = json.dumps(project_data, indent=2, sort_keys=True)
-            zipf.writestr('project.json', project_json)
+            zipf.writestr("project.json", project_json)
 
             # Add all files from the assets folder
             assets_folder = project.asset_manager.assets_folder
@@ -201,20 +201,20 @@ def load_from_zip(zip_path: str, extract_to: Optional[str] = None) -> Project:
         os.makedirs(extract_to, exist_ok=True)
 
     # Extract ZIP contents
-    with zipfile.ZipFile(zip_path, 'r') as zipf:
+    with zipfile.ZipFile(zip_path, "r") as zipf:
         zipf.extractall(extract_to)
 
     # Load project.json
-    project_json_path = os.path.join(extract_to, 'project.json')
+    project_json_path = os.path.join(extract_to, "project.json")
     if not os.path.exists(project_json_path):
         raise ValueError("Invalid project file: project.json not found")
 
-    with open(project_json_path, 'r') as f:
+    with open(project_json_path, "r") as f:
         project_data = json.load(f)
 
     # Check version compatibility
     # Try new version field first, fall back to legacy field
-    file_version = project_data.get('data_version', project_data.get('serialization_version', '1.0'))
+    file_version = project_data.get("data_version", project_data.get("serialization_version", "1.0"))
 
     # Check if version is compatible
     is_compatible, error_msg = check_version_compatibility(file_version, zip_path)
@@ -230,7 +230,7 @@ def load_from_zip(zip_path: str, extract_to: Optional[str] = None) -> Project:
         print(f"Note: Loading project with version {file_version}, current version is {CURRENT_DATA_VERSION}")
 
     # Create new project
-    project_name = project_data.get('name', 'Untitled Project')
+    project_name = project_data.get("name", "Untitled Project")
     project = Project(name=project_name, folder_path=extract_to)
 
     # Deserialize project data
@@ -254,6 +254,7 @@ def load_from_zip(zip_path: str, extract_to: Optional[str] = None) -> Project:
     # Set asset resolution context for ImageData rendering
     # Only set project folder - search paths are reserved for healing functionality
     from pyPhotoAlbum.models import set_asset_resolution_context
+
     set_asset_resolution_context(extract_to)
 
     print(f"Project loaded from {zip_path} to {extract_to}")
@@ -263,25 +264,25 @@ def load_from_zip(zip_path: str, extract_to: Optional[str] = None) -> Project:
 def get_project_info(zip_path: str) -> Optional[dict]:
     """
     Get basic information about a project without fully loading it.
-    
+
     Args:
         zip_path: Path to the ZIP file
-        
+
     Returns:
         Dictionary with project info, or None if error
     """
     try:
-        with zipfile.ZipFile(zip_path, 'r') as zipf:
+        with zipfile.ZipFile(zip_path, "r") as zipf:
             # Read project.json
-            project_json = zipf.read('project.json').decode('utf-8')
+            project_json = zipf.read("project.json").decode("utf-8")
             project_data = json.loads(project_json)
-            
+
             return {
-                'name': project_data.get('name', 'Unknown'),
-                'version': project_data.get('serialization_version', 'Unknown'),
-                'page_count': len(project_data.get('pages', [])),
-                'page_size_mm': project_data.get('page_size_mm', (0, 0)),
-                'working_dpi': project_data.get('working_dpi', 300),
+                "name": project_data.get("name", "Unknown"),
+                "version": project_data.get("serialization_version", "Unknown"),
+                "page_count": len(project_data.get("pages", [])),
+                "page_size_mm": project_data.get("page_size_mm", (0, 0)),
+                "working_dpi": project_data.get("working_dpi", 300),
             }
     except Exception as e:
         print(f"Error reading project info: {e}")
diff --git a/pyPhotoAlbum/ribbon_builder.py b/pyPhotoAlbum/ribbon_builder.py
index 92df0fd..a7b1900 100644
--- a/pyPhotoAlbum/ribbon_builder.py
+++ b/pyPhotoAlbum/ribbon_builder.py
@@ -12,14 +12,14 @@ from collections import defaultdict
 def build_ribbon_config(window_class: Type) -> Dict[str, Any]:
     """
     Extract decorated methods and build ribbon configuration.
-    
+
     This function scans all methods in the window class and its mixins
     for methods decorated with @ribbon_action, then builds a nested
     configuration structure suitable for the RibbonWidget.
-    
+
     Args:
         window_class: The MainWindow class with decorated methods
-        
+
     Returns:
         Dictionary containing the ribbon configuration with structure:
         {
@@ -42,59 +42,61 @@ def build_ribbon_config(window_class: Type) -> Dict[str, Any]:
     """
     # Structure to collect actions by tab and group
     tabs = defaultdict(lambda: defaultdict(list))
-    
+
     # Scan all methods in the class and its bases (mixins)
     for attr_name in dir(window_class):
         try:
             attr = getattr(window_class, attr_name)
-            
+
             # Check if this attribute has ribbon action metadata
-            if hasattr(attr, '_ribbon_action'):
+            if hasattr(attr, "_ribbon_action"):
                 action_data = attr._ribbon_action
-                
+
                 # Extract tab and group information
-                tab_name = action_data['tab']
-                group_name = action_data['group']
-                
+                tab_name = action_data["tab"]
+                group_name = action_data["group"]
+
                 # Add action to the appropriate tab and group
-                tabs[tab_name][group_name].append({
-                    'label': action_data['label'],
-                    'action': action_data['action'],
-                    'tooltip': action_data['tooltip'],
-                    'icon': action_data.get('icon'),
-                    'shortcut': action_data.get('shortcut'),
-                })
+                tabs[tab_name][group_name].append(
+                    {
+                        "label": action_data["label"],
+                        "action": action_data["action"],
+                        "tooltip": action_data["tooltip"],
+                        "icon": action_data.get("icon"),
+                        "shortcut": action_data.get("shortcut"),
+                    }
+                )
         except (AttributeError, TypeError):
             # Skip attributes that can't be inspected
             continue
-    
+
     # Convert to the expected ribbon config format
     ribbon_config = {}
-    
+
     # Define tab order (tabs will appear in this order)
-    tab_order = ['Home', 'Insert', 'Layout', 'Arrange', 'View', 'Export']
-    
+    tab_order = ["Home", "Insert", "Layout", "Arrange", "View", "Export"]
+
     # Add tabs in the defined order, then add any remaining tabs
     all_tabs = list(tabs.keys())
     ordered_tabs = [t for t in tab_order if t in all_tabs]
     ordered_tabs.extend([t for t in all_tabs if t not in tab_order])
-    
+
     for tab_name in ordered_tabs:
         groups_dict = tabs[tab_name]
-        
+
         # Convert groups dictionary to list format
         groups_list = []
-        
+
         # Define group order per tab (if needed)
         group_orders = {
-            'Home': ['File', 'Edit'],
-            'Insert': ['Media'],
-            'Layout': ['Navigation', 'Page', 'Templates'],
-            'Arrange': ['Align', 'Size', 'Distribute'],
-            'View': ['Zoom'],
-            'Export': ['Export'],
+            "Home": ["File", "Edit"],
+            "Insert": ["Media"],
+            "Layout": ["Navigation", "Page", "Templates"],
+            "Arrange": ["Align", "Size", "Distribute"],
+            "View": ["Zoom"],
+            "Export": ["Export"],
         }
-        
+
         # Get the group order for this tab, or use alphabetical
         if tab_name in group_orders:
             group_order = group_orders[tab_name]
@@ -103,139 +105,128 @@ def build_ribbon_config(window_class: Type) -> Dict[str, Any]:
             group_order.extend([g for g in all_groups if g not in group_order])
         else:
             group_order = sorted(groups_dict.keys())
-        
+
         for group_name in group_order:
             if group_name in groups_dict:
                 actions = groups_dict[group_name]
-                groups_list.append({
-                    'name': group_name,
-                    'actions': actions
-                })
-        
-        ribbon_config[tab_name] = {
-            'groups': groups_list
-        }
-    
+                groups_list.append({"name": group_name, "actions": actions})
+
+        ribbon_config[tab_name] = {"groups": groups_list}
+
     return ribbon_config
 
 
 def get_keyboard_shortcuts(window_class: Type) -> Dict[str, str]:
     """
     Extract keyboard shortcuts from decorated methods.
-    
+
     Args:
         window_class: The MainWindow class with decorated methods
-        
+
     Returns:
         Dictionary mapping shortcut strings to method names
         Example: {'Ctrl+N': 'new_project', 'Ctrl+S': 'save_project'}
     """
     shortcuts = {}
-    
+
     for attr_name in dir(window_class):
         try:
             attr = getattr(window_class, attr_name)
-            
-            if hasattr(attr, '_ribbon_action'):
+
+            if hasattr(attr, "_ribbon_action"):
                 action_data = attr._ribbon_action
-                shortcut = action_data.get('shortcut')
-                
+                shortcut = action_data.get("shortcut")
+
                 if shortcut:
-                    shortcuts[shortcut] = action_data['action']
+                    shortcuts[shortcut] = action_data["action"]
         except (AttributeError, TypeError):
             continue
-    
+
     return shortcuts
 
 
 def validate_ribbon_config(config: Dict[str, Any]) -> List[str]:
     """
     Validate the ribbon configuration structure.
-    
+
     Args:
         config: The ribbon configuration dictionary
-        
+
     Returns:
         List of validation error messages (empty if valid)
     """
     errors = []
-    
+
     if not isinstance(config, dict):
         errors.append("Config must be a dictionary")
         return errors
-    
+
     for tab_name, tab_data in config.items():
         if not isinstance(tab_data, dict):
             errors.append(f"Tab '{tab_name}' data must be a dictionary")
             continue
-        
-        if 'groups' not in tab_data:
+
+        if "groups" not in tab_data:
             errors.append(f"Tab '{tab_name}' missing 'groups' key")
             continue
-        
-        groups = tab_data['groups']
+
+        groups = tab_data["groups"]
         if not isinstance(groups, list):
             errors.append(f"Tab '{tab_name}' groups must be a list")
             continue
-        
+
         for i, group in enumerate(groups):
             if not isinstance(group, dict):
                 errors.append(f"Tab '{tab_name}' group {i} must be a dictionary")
                 continue
-            
-            if 'name' not in group:
+
+            if "name" not in group:
                 errors.append(f"Tab '{tab_name}' group {i} missing 'name'")
-            
-            if 'actions' not in group:
+
+            if "actions" not in group:
                 errors.append(f"Tab '{tab_name}' group {i} missing 'actions'")
                 continue
-            
-            actions = group['actions']
+
+            actions = group["actions"]
             if not isinstance(actions, list):
                 errors.append(f"Tab '{tab_name}' group {i} actions must be a list")
                 continue
-            
+
             for j, action in enumerate(actions):
                 if not isinstance(action, dict):
                     errors.append(f"Tab '{tab_name}' group {i} action {j} must be a dictionary")
                     continue
-                
-                required_keys = ['label', 'action', 'tooltip']
+
+                required_keys = ["label", "action", "tooltip"]
                 for key in required_keys:
                     if key not in action:
-                        errors.append(
-                            f"Tab '{tab_name}' group {i} action {j} missing '{key}'"
-                        )
-    
+                        errors.append(f"Tab '{tab_name}' group {i} action {j} missing '{key}'")
+
     return errors
 
 
 def print_ribbon_summary(config: Dict[str, Any]):
     """
     Print a summary of the ribbon configuration.
-    
+
     Args:
         config: The ribbon configuration dictionary
     """
     print("\n=== Ribbon Configuration Summary ===\n")
-    
+
     total_tabs = len(config)
-    total_groups = sum(len(tab_data['groups']) for tab_data in config.values())
-    total_actions = sum(
-        len(group['actions'])
-        for tab_data in config.values()
-        for group in tab_data['groups']
-    )
-    
+    total_groups = sum(len(tab_data["groups"]) for tab_data in config.values())
+    total_actions = sum(len(group["actions"]) for tab_data in config.values() for group in tab_data["groups"])
+
     print(f"Total Tabs: {total_tabs}")
     print(f"Total Groups: {total_groups}")
     print(f"Total Actions: {total_actions}\n")
-    
+
     for tab_name, tab_data in config.items():
         print(f"📑 {tab_name}")
-        for group in tab_data['groups']:
+        for group in tab_data["groups"]:
             print(f"  📦 {group['name']} ({len(group['actions'])} actions)")
-            for action in group['actions']:
-                shortcut = f" ({action['shortcut']})" if action.get('shortcut') else ""
+            for action in group["actions"]:
+                shortcut = f" ({action['shortcut']})" if action.get("shortcut") else ""
                 print(f"    • {action['label']}{shortcut}")
         print()
diff --git a/pyPhotoAlbum/ribbon_widget.py b/pyPhotoAlbum/ribbon_widget.py
index 72d46a3..2f6067a 100644
--- a/pyPhotoAlbum/ribbon_widget.py
+++ b/pyPhotoAlbum/ribbon_widget.py
@@ -17,10 +17,11 @@ class RibbonWidget(QWidget):
         # Use provided config or fall back to importing the old one
         if ribbon_config is None:
             from ribbon_config import RIBBON_CONFIG
+
             self.ribbon_config = RIBBON_CONFIG
         else:
             self.ribbon_config = ribbon_config
-        
+
         # Main layout
         main_layout = QVBoxLayout()
         main_layout.setContentsMargins(0, 0, 0, 0)
diff --git a/pyPhotoAlbum/snapping.py b/pyPhotoAlbum/snapping.py
index 5f37be3..6ea762d 100644
--- a/pyPhotoAlbum/snapping.py
+++ b/pyPhotoAlbum/snapping.py
@@ -11,28 +11,24 @@ from dataclasses import dataclass
 @dataclass
 class Guide:
     """Represents a snapping guide (vertical or horizontal line)"""
+
     position: float  # Position in mm
     orientation: str  # 'vertical' or 'horizontal'
 
     def serialize(self) -> dict:
         """Serialize guide to dictionary"""
-        return {
-            "position": self.position,
-            "orientation": self.orientation
-        }
+        return {"position": self.position, "orientation": self.orientation}
 
     @staticmethod
-    def deserialize(data: dict) -> 'Guide':
+    def deserialize(data: dict) -> "Guide":
         """Deserialize guide from dictionary"""
-        return Guide(
-            position=data.get("position", 0),
-            orientation=data.get("orientation", "vertical")
-        )
+        return Guide(position=data.get("position", 0), orientation=data.get("orientation", "vertical"))
 
 
 @dataclass
 class SnapResizeParams:
     """Parameters for snap resize operations"""
+
     position: Tuple[float, float]
     size: Tuple[float, float]
     dx: float
@@ -45,11 +41,11 @@ class SnapResizeParams:
 
 class SnappingSystem:
     """Manages snapping behavior for layout elements"""
-    
+
     def __init__(self, snap_threshold_mm: float = 5.0):
         """
         Initialize snapping system
-        
+
         Args:
             snap_threshold_mm: Distance in mm within which snapping occurs
         """
@@ -59,28 +55,30 @@ class SnappingSystem:
         self.snap_to_edges = True
         self.snap_to_guides = True
         self.guides: List[Guide] = []
-    
+
     def add_guide(self, position: float, orientation: str):
         """Add a new guide"""
         guide = Guide(position=position, orientation=orientation)
         self.guides.append(guide)
         return guide
-    
+
     def remove_guide(self, guide: Guide):
         """Remove a guide"""
         if guide in self.guides:
             self.guides.remove(guide)
-    
+
     def clear_guides(self):
         """Remove all guides"""
         self.guides.clear()
-    
-    def snap_position(self,
-                     position: Tuple[float, float],
-                     size: Tuple[float, float],
-                     page_size: Tuple[float, float],
-                     dpi: int = 300,
-                     project=None) -> Tuple[float, float]:
+
+    def snap_position(
+        self,
+        position: Tuple[float, float],
+        size: Tuple[float, float],
+        page_size: Tuple[float, float],
+        dpi: int = 300,
+        project=None,
+    ) -> Tuple[float, float]:
         """
         Apply snapping to a position using combined distance threshold
 
@@ -114,43 +112,47 @@ class SnappingSystem:
 
         # Convert threshold from mm to pixels
         snap_threshold_px = snap_threshold_mm * dpi / 25.4
-        
+
         # Collect all potential snap points for both edges of the element
         snap_points = []
-        
+
         # 1. Page edge snap points
         if snap_to_edges:
             page_width_px = page_width_mm * dpi / 25.4
             page_height_px = page_height_mm * dpi / 25.4
 
             # Corners where element's top-left can snap
-            snap_points.extend([
-                (0, 0),  # Top-left corner
-                (page_width_px - width, 0),  # Top-right corner
-                (0, page_height_px - height),  # Bottom-left corner
-                (page_width_px - width, page_height_px - height),  # Bottom-right corner
-            ])
+            snap_points.extend(
+                [
+                    (0, 0),  # Top-left corner
+                    (page_width_px - width, 0),  # Top-right corner
+                    (0, page_height_px - height),  # Bottom-left corner
+                    (page_width_px - width, page_height_px - height),  # Bottom-right corner
+                ]
+            )
 
             # Edge positions (element aligned to edge on one axis)
-            snap_points.extend([
-                (0, y),  # Left edge
-                (page_width_px - width, y),  # Right edge
-                (x, 0),  # Top edge
-                (x, page_height_px - height),  # Bottom edge
-            ])
+            snap_points.extend(
+                [
+                    (0, y),  # Left edge
+                    (page_width_px - width, y),  # Right edge
+                    (x, 0),  # Top edge
+                    (x, page_height_px - height),  # Bottom edge
+                ]
+            )
 
         # 2. Grid snap points
         if snap_to_grid:
             grid_size_px = grid_size_mm * dpi / 25.4
             page_width_px = page_width_mm * dpi / 25.4
             page_height_px = page_height_mm * dpi / 25.4
-            
+
             # Calculate grid intersection points within range
             x_start = max(0, int((x - snap_threshold_px) / grid_size_px)) * grid_size_px
             x_end = min(page_width_px, int((x + snap_threshold_px) / grid_size_px + 1) * grid_size_px)
             y_start = max(0, int((y - snap_threshold_px) / grid_size_px)) * grid_size_px
             y_end = min(page_height_px, int((y + snap_threshold_px) / grid_size_px + 1) * grid_size_px)
-            
+
             grid_x = x_start
             while grid_x <= x_end:
                 grid_y = y_start
@@ -163,12 +165,12 @@ class SnappingSystem:
                         snap_points.append((grid_x, grid_y - height))
                     grid_y += grid_size_px
                 grid_x += grid_size_px
-        
+
         # 3. Guide snap points
         if snap_to_guides:
-            vertical_guides = [g.position * dpi / 25.4 for g in self.guides if g.orientation == 'vertical']
-            horizontal_guides = [g.position * dpi / 25.4 for g in self.guides if g.orientation == 'horizontal']
-            
+            vertical_guides = [g.position * dpi / 25.4 for g in self.guides if g.orientation == "vertical"]
+            horizontal_guides = [g.position * dpi / 25.4 for g in self.guides if g.orientation == "horizontal"]
+
             # Guide intersections (when both vertical and horizontal guides exist)
             for vg in vertical_guides:
                 for hg in horizontal_guides:
@@ -177,23 +179,23 @@ class SnappingSystem:
                     snap_points.append((vg - width, hg))
                     snap_points.append((vg, hg - height))
                     snap_points.append((vg - width, hg - height))
-        
+
         # Find the nearest snap point using Euclidean distance
         best_snap_point = None
         best_distance = snap_threshold_px
-        
+
         for snap_x, snap_y in snap_points:
             distance = math.sqrt((x - snap_x) ** 2 + (y - snap_y) ** 2)
             if distance < best_distance:
                 best_snap_point = (snap_x, snap_y)
                 best_distance = distance
-        
+
         # Return snapped position or original position
         if best_snap_point:
             return best_snap_point
         else:
             return (x, y)
-    
+
     def snap_resize(self, params: SnapResizeParams) -> Tuple[Tuple[float, float], Tuple[float, float]]:
         """
         Apply snapping during resize operations
@@ -222,32 +224,32 @@ class SnappingSystem:
         new_width, new_height = width, height
 
         # Apply resize based on handle
-        if params.resize_handle in ['nw', 'n', 'ne']:
+        if params.resize_handle in ["nw", "n", "ne"]:
             # Top edge moving
             new_y = y + params.dy
             new_height = height - params.dy
 
-        if params.resize_handle in ['sw', 's', 'se']:
+        if params.resize_handle in ["sw", "s", "se"]:
             # Bottom edge moving
             new_height = height + params.dy
 
-        if params.resize_handle in ['nw', 'w', 'sw']:
+        if params.resize_handle in ["nw", "w", "sw"]:
             # Left edge moving
             new_x = x + params.dx
             new_width = width - params.dx
 
-        if params.resize_handle in ['ne', 'e', 'se']:
+        if params.resize_handle in ["ne", "e", "se"]:
             # Right edge moving
             new_width = width + params.dx
-        
+
         # Now apply snapping to the edges that are being moved
         # Use _snap_edge_to_targets consistently for all edges
 
         # Snap left edge (for nw, w, sw handles)
-        if params.resize_handle in ['nw', 'w', 'sw']:
+        if params.resize_handle in ["nw", "w", "sw"]:
             # Try to snap the left edge
             snapped_left = self._snap_edge_to_targets(
-                new_x, page_width_mm, params.dpi, snap_threshold_px, 'vertical', params.project
+                new_x, page_width_mm, params.dpi, snap_threshold_px, "vertical", params.project
             )
             if snapped_left is not None:
                 # Adjust width to compensate for position change
@@ -256,21 +258,21 @@ class SnappingSystem:
                 new_width += width_adjustment
 
         # Snap right edge (for ne, e, se handles)
-        if params.resize_handle in ['ne', 'e', 'se']:
+        if params.resize_handle in ["ne", "e", "se"]:
             # Calculate right edge position
             right_edge = new_x + new_width
             # Try to snap the right edge
             snapped_right = self._snap_edge_to_targets(
-                right_edge, page_width_mm, params.dpi, snap_threshold_px, 'vertical', params.project
+                right_edge, page_width_mm, params.dpi, snap_threshold_px, "vertical", params.project
             )
             if snapped_right is not None:
                 new_width = snapped_right - new_x
 
         # Snap top edge (for nw, n, ne handles)
-        if params.resize_handle in ['nw', 'n', 'ne']:
+        if params.resize_handle in ["nw", "n", "ne"]:
             # Try to snap the top edge
             snapped_top = self._snap_edge_to_targets(
-                new_y, page_height_mm, params.dpi, snap_threshold_px, 'horizontal', params.project
+                new_y, page_height_mm, params.dpi, snap_threshold_px, "horizontal", params.project
             )
             if snapped_top is not None:
                 # Adjust height to compensate for position change
@@ -279,30 +281,32 @@ class SnappingSystem:
                 new_height += height_adjustment
 
         # Snap bottom edge (for sw, s, se handles)
-        if params.resize_handle in ['sw', 's', 'se']:
+        if params.resize_handle in ["sw", "s", "se"]:
             # Calculate bottom edge position
             bottom_edge = new_y + new_height
             # Try to snap the bottom edge
             snapped_bottom = self._snap_edge_to_targets(
-                bottom_edge, page_height_mm, params.dpi, snap_threshold_px, 'horizontal', params.project
+                bottom_edge, page_height_mm, params.dpi, snap_threshold_px, "horizontal", params.project
             )
             if snapped_bottom is not None:
                 new_height = snapped_bottom - new_y
-        
+
         # Ensure minimum size
         min_size = 10  # Minimum 10 pixels
         new_width = max(new_width, min_size)
         new_height = max(new_height, min_size)
-        
+
         return ((new_x, new_y), (new_width, new_height))
-    
-    def _snap_edge_to_targets(self,
-                              edge_position: float,
-                              page_size_mm: float,
-                              dpi: int,
-                              snap_threshold_px: float,
-                              orientation: str,
-                              project=None) -> Optional[float]:
+
+    def _snap_edge_to_targets(
+        self,
+        edge_position: float,
+        page_size_mm: float,
+        dpi: int,
+        snap_threshold_px: float,
+        orientation: str,
+        project=None,
+    ) -> Optional[float]:
         """
         Snap an edge position to available targets (grid, edges, guides)
 
@@ -354,28 +358,24 @@ class SnappingSystem:
                 if guide.orientation == orientation:
                     guide_pos_px = guide.position * dpi / 25.4
                     snap_candidates.append((guide_pos_px, abs(edge_position - guide_pos_px)))
-        
+
         # Find the best snap candidate within threshold
         best_snap = None
         best_distance = snap_threshold_px
-        
+
         for snap_pos, distance in snap_candidates:
             if distance < best_distance:
                 best_snap = snap_pos
                 best_distance = distance
-        
+
         return best_snap
-    
-    def _snap_axis(self, 
-                   position: float, 
-                   size: float,
-                   page_size_mm: float,
-                   dpi: int,
-                   snap_threshold_px: float,
-                   orientation: str) -> float:
+
+    def _snap_axis(
+        self, position: float, size: float, page_size_mm: float, dpi: int, snap_threshold_px: float, orientation: str
+    ) -> float:
         """
         Snap along a single axis
-        
+
         Args:
             position: Current position along axis in pixels
             size: Element size along axis in pixels
@@ -383,115 +383,108 @@ class SnappingSystem:
             dpi: DPI for conversion
             snap_threshold_px: Snap threshold in pixels
             orientation: 'vertical' for x-axis, 'horizontal' for y-axis
-            
+
         Returns:
             Snapped position in pixels
         """
         snap_candidates = []
-        
+
         # 1. Page edge snapping
         if self.snap_to_edges:
             # Snap to start edge (0)
             snap_candidates.append((0, abs(position - 0)))
-            
+
             # Snap to end edge
             page_size_px = page_size_mm * dpi / 25.4
             snap_candidates.append((page_size_px - size, abs(position - (page_size_px - size))))
-            
+
             # Also snap element's far edge to page edge
             snap_candidates.append((page_size_px - size, abs((position + size) - page_size_px)))
-        
+
         # 2. Grid snapping
         if self.snap_to_grid:
             grid_size_px = self.grid_size_mm * dpi / 25.4
-            
+
             # Snap to nearest grid line
             nearest_grid = round(position / grid_size_px) * grid_size_px
             snap_candidates.append((nearest_grid, abs(position - nearest_grid)))
-            
+
             # Also try snapping element's far edge to grid
             element_end = position + size
             nearest_grid_end = round(element_end / grid_size_px) * grid_size_px
             snap_candidates.append((nearest_grid_end - size, abs(element_end - nearest_grid_end)))
-        
+
         # 3. Guide snapping
         if self.snap_to_guides:
             for guide in self.guides:
                 if guide.orientation == orientation:
                     guide_pos_px = guide.position * dpi / 25.4
-                    
+
                     # Snap start edge to guide
                     snap_candidates.append((guide_pos_px, abs(position - guide_pos_px)))
-                    
+
                     # Snap end edge to guide
                     element_end = position + size
                     snap_candidates.append((guide_pos_px - size, abs(element_end - guide_pos_px)))
-        
+
         # Find the best snap candidate within threshold
         best_snap = None
         best_distance = snap_threshold_px
-        
+
         for snap_pos, distance in snap_candidates:
             if distance < best_distance:
                 best_snap = snap_pos
                 best_distance = distance
-        
+
         return best_snap if best_snap is not None else position
-    
+
     def get_snap_lines(self, page_size: Tuple[float, float], dpi: int = 300) -> dict:
         """
         Get all snap lines for visualization
-        
+
         Args:
             page_size: Page size (width, height) in mm
             dpi: DPI for conversion
-            
+
         Returns:
             Dictionary with 'grid', 'edges', and 'guides' lists
         """
         page_width_mm, page_height_mm = page_size
         page_width_px = page_width_mm * dpi / 25.4
         page_height_px = page_height_mm * dpi / 25.4
-        
-        result = {
-            'grid': [],
-            'edges': [],
-            'guides': []
-        }
-        
+
+        result = {"grid": [], "edges": [], "guides": []}
+
         # Grid lines
         if self.snap_to_grid:
             grid_size_px = self.grid_size_mm * dpi / 25.4
-            
+
             # Vertical grid lines
             x = 0
             while x <= page_width_px:
-                result['grid'].append(('vertical', x))
+                result["grid"].append(("vertical", x))
                 x += grid_size_px
-            
+
             # Horizontal grid lines
             y = 0
             while y <= page_height_px:
-                result['grid'].append(('horizontal', y))
+                result["grid"].append(("horizontal", y))
                 y += grid_size_px
-        
+
         # Edge lines
         if self.snap_to_edges:
-            result['edges'].extend([
-                ('vertical', 0),
-                ('vertical', page_width_px),
-                ('horizontal', 0),
-                ('horizontal', page_height_px)
-            ])
-        
+            result["edges"].extend(
+                [("vertical", 0), ("vertical", page_width_px), ("horizontal", 0), ("horizontal", page_height_px)]
+            )
+
         # Guide lines
         if self.snap_to_guides:
             for guide in self.guides:
                 guide_pos_px = guide.position * dpi / 25.4
-                result['guides'].append((guide.orientation, guide_pos_px))
-        
+                result["guides"].append((guide.orientation, guide_pos_px))
+
         return result
-    
+
     def serialize(self) -> dict:
         """Serialize snapping system to dictionary"""
         return {
@@ -500,9 +493,9 @@ class SnappingSystem:
             "snap_to_grid": self.snap_to_grid,
             "snap_to_edges": self.snap_to_edges,
             "snap_to_guides": self.snap_to_guides,
-            "guides": [guide.serialize() for guide in self.guides]
+            "guides": [guide.serialize() for guide in self.guides],
         }
-    
+
     def deserialize(self, data: dict):
         """Deserialize from dictionary"""
         self.snap_threshold_mm = data.get("snap_threshold_mm", 5.0)
@@ -510,7 +503,7 @@ class SnappingSystem:
         self.snap_to_grid = data.get("snap_to_grid", False)
         self.snap_to_edges = data.get("snap_to_edges", True)
         self.snap_to_guides = data.get("snap_to_guides", True)
-        
+
         self.guides = []
         for guide_data in data.get("guides", []):
             self.guides.append(Guide.deserialize(guide_data))
diff --git a/pyPhotoAlbum/template_manager.py b/pyPhotoAlbum/template_manager.py
index bfbacd2..c109fc2 100644
--- a/pyPhotoAlbum/template_manager.py
+++ b/pyPhotoAlbum/template_manager.py
@@ -14,7 +14,9 @@ from pyPhotoAlbum.project import Page
 class Template:
     """Class representing a page layout template"""
 
-    def __init__(self, name: str = "Untitled Template", description: str = "", page_size_mm: Tuple[float, float] = (210, 297)):
+    def __init__(
+        self, name: str = "Untitled Template", description: str = "", page_size_mm: Tuple[float, float] = (210, 297)
+    ):
         self.name = name
         self.description = description
         self.page_size_mm = page_size_mm
@@ -30,16 +32,16 @@ class Template:
             "name": self.name,
             "description": self.description,
             "page_size_mm": self.page_size_mm,
-            "elements": [elem.serialize() for elem in self.elements]
+            "elements": [elem.serialize() for elem in self.elements],
         }
 
     @classmethod
-    def from_dict(cls, data: Dict[str, Any]) -> 'Template':
+    def from_dict(cls, data: Dict[str, Any]) -> "Template":
         """Deserialize template from dictionary"""
         template = cls(
             name=data.get("name", "Untitled Template"),
             description=data.get("description", ""),
-            page_size_mm=tuple(data.get("page_size_mm", (210, 297)))
+            page_size_mm=tuple(data.get("page_size_mm", (210, 297))),
         )
 
         # Deserialize elements
@@ -59,13 +61,13 @@ class Template:
 
     def save_to_file(self, file_path: str):
         """Save template to JSON file"""
-        with open(file_path, 'w') as f:
+        with open(file_path, "w") as f:
             json.dump(self.to_dict(), f, indent=2)
 
     @classmethod
-    def load_from_file(cls, file_path: str) -> 'Template':
+    def load_from_file(cls, file_path: str) -> "Template":
         """Load template from JSON file"""
-        with open(file_path, 'r') as f:
+        with open(file_path, "r") as f:
             data = json.load(f)
         return cls.from_dict(data)
 
@@ -94,7 +96,7 @@ class TemplateManager:
     def _ensure_templates_directory(self):
         """Create templates directory if it doesn't exist"""
         self.templates_dir.mkdir(parents=True, exist_ok=True)
-        
+
         # Also ensure built-in templates directory exists
         builtin_dir = self._get_builtin_templates_directory()
         builtin_dir.mkdir(parents=True, exist_ok=True)
@@ -102,33 +104,33 @@ class TemplateManager:
     def list_templates(self) -> List[str]:
         """List all available template names (embedded + user + built-in)"""
         templates = []
-        
+
         # List embedded templates (priority)
         if self.project and self.project.embedded_templates:
             for template_name in self.project.embedded_templates.keys():
                 templates.append(f"[Embedded] {template_name}")
-        
+
         # List user templates
         if self.templates_dir.exists():
             for file in self.templates_dir.glob("*.json"):
                 templates.append(file.stem)
-        
+
         # List built-in templates
         builtin_dir = self._get_builtin_templates_directory()
         if builtin_dir.exists():
             for file in builtin_dir.glob("*.json"):
                 template_name = f"[Built-in] {file.stem}"
                 templates.append(template_name)
-        
+
         return sorted(templates)
 
     def load_template(self, name: str) -> Template:
         """
         Load a template by name with priority: embedded > user > built-in.
-        
+
         Args:
             name: Template name (may include prefix like '[Embedded]' or '[Built-in]')
-        
+
         Returns:
             Template instance
         """
@@ -139,12 +141,12 @@ class TemplateManager:
                 template_data = self.project.embedded_templates[actual_name]
                 return Template.from_dict(template_data)
             raise FileNotFoundError(f"Embedded template '{actual_name}' not found")
-        
+
         # Check embedded templates even without prefix (for backward compatibility)
         if self.project and name in self.project.embedded_templates:
             template_data = self.project.embedded_templates[name]
             return Template.from_dict(template_data)
-        
+
         # Check if it's a built-in template
         if name.startswith("[Built-in] "):
             actual_name = name.replace("[Built-in] ", "")
@@ -152,16 +154,16 @@ class TemplateManager:
         else:
             # User template
             template_path = self.templates_dir / f"{name}.json"
-        
+
         if not template_path.exists():
             raise FileNotFoundError(f"Template '{name}' not found")
-        
+
         return Template.load_from_file(str(template_path))
 
     def save_template(self, template: Template, embed_in_project: bool = False):
         """
         Save a template to filesystem or embed in project.
-        
+
         Args:
             template: Template to save
             embed_in_project: If True, embed in project instead of saving to filesystem
@@ -179,7 +181,7 @@ class TemplateManager:
         """Delete a template (embedded or user templates only)"""
         if name.startswith("[Built-in] "):
             raise PermissionError("Cannot delete built-in templates")
-        
+
         # Check if it's an embedded template
         if name.startswith("[Embedded] "):
             actual_name = name.replace("[Embedded] ", "")
@@ -188,7 +190,7 @@ class TemplateManager:
                 print(f"Removed embedded template '{actual_name}'")
                 return
             raise FileNotFoundError(f"Embedded template '{actual_name}' not found")
-        
+
         # User template from filesystem
         template_path = self.templates_dir / f"{name}.json"
         if template_path.exists():
@@ -197,26 +199,22 @@ class TemplateManager:
     def embed_template(self, template: Template):
         """
         Embed a template in the project.
-        
+
         Args:
             template: Template to embed
         """
         if not self.project:
             raise RuntimeError("No project associated with this TemplateManager")
-        
+
         self.project.embedded_templates[template.name] = template.to_dict()
         print(f"Embedded template '{template.name}' in project")
-    
+
     def create_template_from_page(self, page: Page, name: str, description: str = "") -> Template:
         """
         Create a template from an existing page.
         Converts all ImageData elements to PlaceholderData.
         """
-        template = Template(
-            name=name,
-            description=description,
-            page_size_mm=page.layout.size
-        )
+        template = Template(name=name, description=description, page_size_mm=page.layout.size)
 
         # Convert elements
         for element in page.layout.elements:
@@ -229,7 +227,7 @@ class TemplateManager:
                     width=element.size[0],
                     height=element.size[1],
                     rotation=element.rotation,
-                    z_index=element.z_index
+                    z_index=element.z_index,
                 )
                 template.add_element(placeholder)
             elif isinstance(element, TextBoxData):
@@ -243,7 +241,7 @@ class TemplateManager:
                     width=element.size[0],
                     height=element.size[1],
                     rotation=element.rotation,
-                    z_index=element.z_index
+                    z_index=element.z_index,
                 )
                 template.add_element(text_box)
             elif isinstance(element, PlaceholderData):
@@ -256,7 +254,7 @@ class TemplateManager:
                     width=element.size[0],
                     height=element.size[1],
                     rotation=element.rotation,
-                    z_index=element.z_index
+                    z_index=element.z_index,
                 )
                 template.add_element(placeholder)
 
@@ -268,32 +266,32 @@ class TemplateManager:
         from_size: Tuple[float, float],
         to_size: Tuple[float, float],
         scale_mode: str = "proportional",
-        margin_percent: float = 0.0
+        margin_percent: float = 0.0,
     ) -> List[BaseLayoutElement]:
         """
         Scale template elements to fit target page size with adjustable margins.
-        
+
         Args:
             elements: List of elements to scale
             from_size: Original template size (width, height) in mm
             to_size: Target page size (width, height) in mm
             scale_mode: "proportional", "stretch", or "center"
             margin_percent: Percentage of page size to use for margins (0-10%)
-        
+
         Returns:
             List of scaled elements
         """
         from_width, from_height = from_size
         to_width, to_height = to_size
-        
+
         # Calculate target margins from percentage
         margin_x = to_width * (margin_percent / 100.0)
         margin_y = to_height * (margin_percent / 100.0)
-        
+
         # Available content area after margins
         content_width = to_width - (2 * margin_x)
         content_height = to_height - (2 * margin_y)
-        
+
         # Calculate scale factors based on mode
         if scale_mode == "stretch":
             # Stretch to fill content area independently in each dimension
@@ -323,14 +321,13 @@ class TemplateManager:
             # Create a new element of the same type
             if isinstance(element, PlaceholderData):
                 new_elem = PlaceholderData(
-                    placeholder_type=element.placeholder_type,
-                    default_content=element.default_content
+                    placeholder_type=element.placeholder_type, default_content=element.default_content
                 )
             elif isinstance(element, TextBoxData):
                 new_elem = TextBoxData(
                     text_content=element.text_content,
                     font_settings=element.font_settings.copy() if element.font_settings else None,
-                    alignment=element.alignment
+                    alignment=element.alignment,
                 )
             else:
                 continue  # Skip other types
@@ -339,14 +336,8 @@ class TemplateManager:
             old_x, old_y = element.position
             old_w, old_h = element.size
 
-            new_elem.position = (
-                old_x * scale_x + offset_x,
-                old_y * scale_y + offset_y
-            )
-            new_elem.size = (
-                old_w * scale_x,
-                old_h * scale_y
-            )
+            new_elem.position = (old_x * scale_x + offset_x, old_y * scale_y + offset_y)
+            new_elem.size = (old_w * scale_x, old_h * scale_y)
             new_elem.rotation = element.rotation
             new_elem.z_index = element.z_index
 
@@ -362,15 +353,9 @@ class TemplateManager:
 
         for elem in scaled_elements:
             # Convert position from mm to pixels
-            elem.position = (
-                elem.position[0] * mm_to_px,
-                elem.position[1] * mm_to_px
-            )
+            elem.position = (elem.position[0] * mm_to_px, elem.position[1] * mm_to_px)
             # Convert size from mm to pixels
-            elem.size = (
-                elem.size[0] * mm_to_px,
-                elem.size[1] * mm_to_px
-            )
+            elem.size = (elem.size[0] * mm_to_px, elem.size[1] * mm_to_px)
 
         return scaled_elements
 
@@ -381,15 +366,15 @@ class TemplateManager:
         mode: str = "replace",
         scale_mode: str = "proportional",
         margin_percent: float = 2.5,
-        auto_embed: bool = True
+        auto_embed: bool = True,
     ):
         """
         Apply template to an existing page with adjustable margins.
-        
+
         Args:
             template: Template to apply
             page: Target page
-            mode: "replace" to clear page and add placeholders, 
+            mode: "replace" to clear page and add placeholders,
                   "reflow" to keep existing content and reposition
             scale_mode: "proportional", "stretch", or "center"
             margin_percent: Percentage of page size to use for margins (0-10%)
@@ -399,44 +384,36 @@ class TemplateManager:
         if auto_embed and self.project:
             if template.name not in self.project.embedded_templates:
                 self.embed_template(template)
-        
+
         if mode == "replace":
             # Clear existing elements
             page.layout.elements.clear()
-            
+
             # Scale template elements to fit page
             scaled_elements = self.scale_template_elements(
-                template.elements,
-                template.page_size_mm,
-                page.layout.size,
-                scale_mode,
-                margin_percent
+                template.elements, template.page_size_mm, page.layout.size, scale_mode, margin_percent
             )
-            
+
             # Add scaled elements to page
             for element in scaled_elements:
                 page.layout.add_element(element)
-        
+
         elif mode == "reflow":
             # Keep existing content but reposition to template slots
             existing_images = [e for e in page.layout.elements if isinstance(e, ImageData)]
             existing_text = [e for e in page.layout.elements if isinstance(e, TextBoxData)]
-            
+
             # Get template placeholders (scaled)
             scaled_elements = self.scale_template_elements(
-                template.elements,
-                template.page_size_mm,
-                page.layout.size,
-                scale_mode,
-                margin_percent
+                template.elements, template.page_size_mm, page.layout.size, scale_mode, margin_percent
             )
-            
+
             template_placeholders = [e for e in scaled_elements if isinstance(e, PlaceholderData)]
             template_text = [e for e in scaled_elements if isinstance(e, TextBoxData)]
-            
+
             # Clear page
             page.layout.elements.clear()
-            
+
             # Reflow images into placeholder slots
             for i, placeholder in enumerate(template_placeholders):
                 if i < len(existing_images):
@@ -449,11 +426,11 @@ class TemplateManager:
                 else:
                     # Add placeholder if no more images
                     page.layout.add_element(placeholder)
-            
+
             # Add remaining images (if any) at their original positions
-            for img in existing_images[len(template_placeholders):]:
+            for img in existing_images[len(template_placeholders) :]:
                 page.layout.add_element(img)
-            
+
             # Add template text boxes
             for text_elem in template_text:
                 page.layout.add_element(text_elem)
@@ -465,7 +442,7 @@ class TemplateManager:
         target_size_mm: Optional[Tuple[float, float]] = None,
         scale_mode: str = "proportional",
         margin_percent: float = 2.5,
-        auto_embed: bool = True
+        auto_embed: bool = True,
     ) -> Page:
         """
         Create a new page from a template.
@@ -494,11 +471,7 @@ class TemplateManager:
             page_size = target_size_mm
             # Scale template elements with margins
             elements = self.scale_template_elements(
-                template.elements,
-                template.page_size_mm,
-                target_size_mm,
-                scale_mode,
-                margin_percent
+                template.elements, template.page_size_mm, target_size_mm, scale_mode, margin_percent
             )
 
         # Create new page layout
diff --git a/pyPhotoAlbum/text_edit_dialog.py b/pyPhotoAlbum/text_edit_dialog.py
index 34edfe8..df74fe4 100644
--- a/pyPhotoAlbum/text_edit_dialog.py
+++ b/pyPhotoAlbum/text_edit_dialog.py
@@ -3,8 +3,15 @@ Text editing dialog for pyPhotoAlbum
 """
 
 from PyQt6.QtWidgets import (
-    QDialog, QVBoxLayout, QHBoxLayout, QPushButton, 
-    QTextEdit, QLabel, QComboBox, QSpinBox, QColorDialog
+    QDialog,
+    QVBoxLayout,
+    QHBoxLayout,
+    QPushButton,
+    QTextEdit,
+    QLabel,
+    QComboBox,
+    QSpinBox,
+    QColorDialog,
 )
 from PyQt6.QtCore import Qt
 from PyQt6.QtGui import QFont, QColor
@@ -12,58 +19,57 @@ from PyQt6.QtGui import QFont, QColor
 
 class TextEditDialog(QDialog):
     """Dialog for editing text box content and properties"""
-    
+
     def __init__(self, text_element, parent=None):
         super().__init__(parent)
         self.text_element = text_element
         self.setWindowTitle("Edit Text")
         self.resize(500, 400)
-        
+
         # Create UI
         self._init_ui()
-        
+
         # Load current values
         self._load_values()
-    
+
     def _init_ui(self):
         """Initialize the user interface"""
         layout = QVBoxLayout()
-        
+
         # Text editor
         text_label = QLabel("Text:")
         self.text_edit = QTextEdit()
         self.text_edit.setAcceptRichText(False)  # Plain text only
         layout.addWidget(text_label)
         layout.addWidget(self.text_edit)
-        
+
         # Font settings
         font_layout = QHBoxLayout()
-        
+
         # Font family
         font_layout.addWidget(QLabel("Font:"))
         self.font_combo = QComboBox()
-        self.font_combo.addItems([
-            "Arial", "Times New Roman", "Courier New", 
-            "Helvetica", "Verdana", "Georgia", "Comic Sans MS"
-        ])
+        self.font_combo.addItems(
+            ["Arial", "Times New Roman", "Courier New", "Helvetica", "Verdana", "Georgia", "Comic Sans MS"]
+        )
         font_layout.addWidget(self.font_combo)
-        
+
         # Font size
         font_layout.addWidget(QLabel("Size:"))
         self.font_size_spin = QSpinBox()
         self.font_size_spin.setRange(6, 72)
         self.font_size_spin.setValue(12)
         font_layout.addWidget(self.font_size_spin)
-        
+
         # Text color
         self.color_button = QPushButton("Color")
         self.color_button.clicked.connect(self._choose_color)
         self.current_color = QColor(0, 0, 0)  # Default black
         font_layout.addWidget(self.color_button)
-        
+
         font_layout.addStretch()
         layout.addLayout(font_layout)
-        
+
         # Alignment
         alignment_layout = QHBoxLayout()
         alignment_layout.addWidget(QLabel("Alignment:"))
@@ -72,84 +78,76 @@ class TextEditDialog(QDialog):
         alignment_layout.addWidget(self.alignment_combo)
         alignment_layout.addStretch()
         layout.addLayout(alignment_layout)
-        
+
         # Buttons
         button_layout = QHBoxLayout()
         button_layout.addStretch()
-        
+
         cancel_button = QPushButton("Cancel")
         cancel_button.clicked.connect(self.reject)
         button_layout.addWidget(cancel_button)
-        
+
         ok_button = QPushButton("OK")
         ok_button.clicked.connect(self.accept)
         ok_button.setDefault(True)
         button_layout.addWidget(ok_button)
-        
+
         layout.addLayout(button_layout)
-        
+
         self.setLayout(layout)
-    
+
     def _load_values(self):
         """Load current values from text element"""
         # Load text content
         self.text_edit.setPlainText(self.text_element.text_content)
-        
+
         # Load font settings
-        font_family = self.text_element.font_settings.get('family', 'Arial')
+        font_family = self.text_element.font_settings.get("family", "Arial")
         index = self.font_combo.findText(font_family)
         if index >= 0:
             self.font_combo.setCurrentIndex(index)
-        
-        font_size = self.text_element.font_settings.get('size', 12)
+
+        font_size = self.text_element.font_settings.get("size", 12)
         self.font_size_spin.setValue(int(font_size))
-        
+
         # Load color
-        color = self.text_element.font_settings.get('color', (0, 0, 0))
+        color = self.text_element.font_settings.get("color", (0, 0, 0))
         if all(isinstance(c, int) and c > 1 for c in color):
             # Color in 0-255 range
             self.current_color = QColor(*color)
         else:
             # Color in 0-1 range
-            self.current_color = QColor(
-                int(color[0] * 255),
-                int(color[1] * 255),
-                int(color[2] * 255)
-            )
+            self.current_color = QColor(int(color[0] * 255), int(color[1] * 255), int(color[2] * 255))
         self._update_color_button()
-        
+
         # Load alignment
         alignment = self.text_element.alignment
         index = self.alignment_combo.findText(alignment)
         if index >= 0:
             self.alignment_combo.setCurrentIndex(index)
-    
+
     def _choose_color(self):
         """Open color picker dialog"""
         color = QColorDialog.getColor(self.current_color, self, "Choose Text Color")
         if color.isValid():
             self.current_color = color
             self._update_color_button()
-    
+
     def _update_color_button(self):
         """Update color button appearance"""
         self.color_button.setStyleSheet(
             f"background-color: {self.current_color.name()}; "
             f"color: {'white' if self.current_color.lightness() < 128 else 'black'};"
         )
-    
+
     def get_values(self):
         """Get the edited values"""
         return {
-            'text_content': self.text_edit.toPlainText(),
-            'font_settings': {
-                'family': self.font_combo.currentText(),
-                'size': self.font_size_spin.value(),
-                'color': (
-                    self.current_color.red(),
-                    self.current_color.green(),
-                    self.current_color.blue()
-                )
+            "text_content": self.text_edit.toPlainText(),
+            "font_settings": {
+                "family": self.font_combo.currentText(),
+                "size": self.font_size_spin.value(),
+                "color": (self.current_color.red(), self.current_color.green(), self.current_color.blue()),
             },
-            'alignment': self.alignment_combo.currentText()
+            "alignment": self.alignment_combo.currentText(),
         }
diff --git a/pyPhotoAlbum/version_manager.py b/pyPhotoAlbum/version_manager.py
index 84b073e..9062d84 100644
--- a/pyPhotoAlbum/version_manager.py
+++ b/pyPhotoAlbum/version_manager.py
@@ -24,7 +24,7 @@ VERSION_HISTORY = {
         "released": "2025-01-11",
         "breaking_changes": [
             "Asset paths changed from absolute/full-project-relative to project-relative",
-            "Added automatic path normalization for legacy projects"
+            "Added automatic path normalization for legacy projects",
         ],
         "compatible_with": ["1.0", "2.0"],  # 2.0 can read 1.0 with migration
     },
@@ -38,7 +38,7 @@ VERSION_HISTORY = {
             "Added deletion tracking (deleted flag and deleted_at timestamp)",
         ],
         "compatible_with": ["1.0", "2.0", "3.0"],  # 3.0 can read older versions with migration
-    }
+    },
 }
 
 
@@ -120,9 +120,11 @@ class DataMigration:
     @classmethod
     def register_migration(cls, from_version: str, to_version: str):
         """Decorator to register a migration function"""
+
         def decorator(func):
             cls._migrations[(from_version, to_version)] = func
             return func
+
         return decorator
 
     @classmethod
@@ -164,6 +166,7 @@ class DataMigration:
 
 # Register migrations
 
+
 @DataMigration.register_migration("1.0", "2.0")
 def migrate_1_0_to_2_0(data: Dict[str, Any]) -> Dict[str, Any]:
     """
@@ -176,7 +179,7 @@ def migrate_1_0_to_2_0(data: Dict[str, Any]) -> Dict[str, Any]:
     print("Migration 1.0 → 2.0: Asset paths will be normalized during load")
 
     # Update version in data
-    data['data_version'] = "2.0"
+    data["data_version"] = "2.0"
 
     # Note: Actual path normalization is handled in load_from_zip
     # This migration mainly updates the version number
@@ -249,7 +252,7 @@ def migrate_2_0_to_3_0(data: Dict[str, Any]) -> Dict[str, Any]:
                 element_data["deleted_at"] = None
 
     # Update version
-    data['data_version'] = "3.0"
+    data["data_version"] = "3.0"
 
     print(f"  Migrated {len(data.get('pages', []))} pages to v3.0")
 
@@ -287,7 +290,7 @@ def check_version_compatibility(file_version: str, file_path: str = "") -> tuple
         error_msg += f"File version info:\n"
         error_msg += f"  Description: {file_info.get('description', 'Unknown')}\n"
         error_msg += f"  Released: {file_info.get('released', 'Unknown')}\n"
-        breaking_changes = file_info.get('breaking_changes', [])
+        breaking_changes = file_info.get("breaking_changes", [])
         if breaking_changes:
             error_msg += f"  Breaking changes:\n"
             for change in breaking_changes:
@@ -312,7 +315,7 @@ def format_version_info() -> str:
         info.append(f"    Description: {version_info.get('description', 'Unknown')}")
         info.append(f"    Released: {version_info.get('released', 'Unknown')}")
 
-        breaking_changes = version_info.get('breaking_changes', [])
+        breaking_changes = version_info.get("breaking_changes", [])
         if breaking_changes:
             info.append(f"    Breaking changes:")
             for change in breaking_changes:
diff --git a/tests/conftest.py b/tests/conftest.py
index 801c5f3..20b4b39 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -15,9 +15,9 @@ from pyPhotoAlbum.project import Project, Page
 @pytest.fixture
 def temp_image_file():
     """Create a temporary test image file"""
-    with tempfile.NamedTemporaryFile(suffix='.png', delete=False) as f:
+    with tempfile.NamedTemporaryFile(suffix=".png", delete=False) as f:
         # Create a simple test image
-        img = Image.new('RGB', (100, 100), color='red')
+        img = Image.new("RGB", (100, 100), color="red")
         img.save(f.name)
         yield f.name
     # Cleanup
@@ -37,37 +37,19 @@ def temp_dir():
 @pytest.fixture
 def sample_image_data(temp_image_file):
     """Create a sample ImageData instance"""
-    return ImageData(
-        image_path=temp_image_file,
-        x=10.0,
-        y=20.0,
-        width=100.0,
-        height=150.0
-    )
+    return ImageData(image_path=temp_image_file, x=10.0, y=20.0, width=100.0, height=150.0)
 
 
 @pytest.fixture
 def sample_placeholder_data():
     """Create a sample PlaceholderData instance"""
-    return PlaceholderData(
-        placeholder_type="image",
-        x=50.0,
-        y=60.0,
-        width=200.0,
-        height=150.0
-    )
+    return PlaceholderData(placeholder_type="image", x=50.0, y=60.0, width=200.0, height=150.0)
 
 
 @pytest.fixture
 def sample_textbox_data():
     """Create a sample TextBoxData instance"""
-    return TextBoxData(
-        text_content="Sample Text",
-        x=30.0,
-        y=40.0,
-        width=150.0,
-        height=50.0
-    )
+    return TextBoxData(text_content="Sample Text", x=30.0, y=40.0, width=150.0, height=50.0)
 
 
 @pytest.fixture
@@ -119,10 +101,7 @@ def mock_main_window():
     window.project = Project(name="Test Project")
 
     # Add a test page
-    page = Page(
-        layout=PageLayout(width=210, height=297),  # A4 size in mm
-        page_number=1
-    )
+    page = Page(layout=PageLayout(width=210, height=297), page_number=1)  # A4 size in mm
     window.project.pages.append(page)
     window.project.working_dpi = 96
     window.project.page_size_mm = (210, 297)
@@ -139,39 +118,19 @@ def mock_main_window():
 @pytest.fixture
 def sample_image_element():
     """Create a sample ImageData element for testing"""
-    return ImageData(
-        image_path="test.jpg",
-        x=100,
-        y=100,
-        width=200,
-        height=150,
-        z_index=1
-    )
+    return ImageData(image_path="test.jpg", x=100, y=100, width=200, height=150, z_index=1)
 
 
 @pytest.fixture
 def sample_placeholder_element():
     """Create a sample PlaceholderData element for testing"""
-    return PlaceholderData(
-        x=50,
-        y=50,
-        width=100,
-        height=100,
-        z_index=0
-    )
+    return PlaceholderData(x=50, y=50, width=100, height=100, z_index=0)
 
 
 @pytest.fixture
 def sample_textbox_element():
     """Create a sample TextBoxData element for testing"""
-    return TextBoxData(
-        x=10,
-        y=10,
-        width=180,
-        height=50,
-        text_content="Test Text",
-        z_index=2
-    )
+    return TextBoxData(x=10, y=10, width=180, height=50, text_content="Test Text", z_index=2)
 
 
 @pytest.fixture
@@ -189,19 +148,19 @@ def mock_page_renderer():
 
     # Mock coordinate conversion methods
     def page_to_screen(x, y):
-        return (renderer.screen_x + x * renderer.zoom,
-                renderer.screen_y + y * renderer.zoom)
+        return (renderer.screen_x + x * renderer.zoom, renderer.screen_y + y * renderer.zoom)
 
     def screen_to_page(x, y):
-        return ((x - renderer.screen_x) / renderer.zoom,
-                (y - renderer.screen_y) / renderer.zoom)
+        return ((x - renderer.screen_x) / renderer.zoom, (y - renderer.screen_y) / renderer.zoom)
 
     def is_point_in_page(x, y):
         # Simple bounds check (assume 210mm x 297mm page at 96 DPI)
         page_width_px = 210 * 96 / 25.4
         page_height_px = 297 * 96 / 25.4
-        return (renderer.screen_x <= x <= renderer.screen_x + page_width_px * renderer.zoom and
-                renderer.screen_y <= y <= renderer.screen_y + page_height_px * renderer.zoom)
+        return (
+            renderer.screen_x <= x <= renderer.screen_x + page_width_px * renderer.zoom
+            and renderer.screen_y <= y <= renderer.screen_y + page_height_px * renderer.zoom
+        )
 
     renderer.page_to_screen = page_to_screen
     renderer.screen_to_page = screen_to_page
@@ -213,8 +172,8 @@ def mock_page_renderer():
 @pytest.fixture
 def create_mouse_event():
     """Factory fixture for creating QMouseEvent objects"""
-    def _create_event(event_type, x, y, button=Qt.MouseButton.LeftButton,
-                     modifiers=Qt.KeyboardModifier.NoModifier):
+
+    def _create_event(event_type, x, y, button=Qt.MouseButton.LeftButton, modifiers=Qt.KeyboardModifier.NoModifier):
         """Create a QMouseEvent for testing
 
         Args:
@@ -224,19 +183,15 @@ def create_mouse_event():
             modifiers: Keyboard modifiers
         """
         pos = QPointF(x, y)
-        return QMouseEvent(
-            event_type,
-            pos,
-            button,
-            button,
-            modifiers
-        )
+        return QMouseEvent(event_type, pos, button, button, modifiers)
+
     return _create_event
 
 
 @pytest.fixture
 def create_wheel_event():
     """Factory fixture for creating QWheelEvent objects"""
+
     def _create_event(x, y, delta_y=120, modifiers=Qt.KeyboardModifier.NoModifier):
         """Create a QWheelEvent for testing
 
@@ -257,38 +212,22 @@ def create_wheel_event():
             Qt.MouseButton.NoButton,
             modifiers,
             Qt.ScrollPhase.NoScrollPhase,
-            False
+            False,
         )
+
     return _create_event
 
 
 @pytest.fixture
 def populated_page():
     """Create a page with multiple elements for testing"""
-    page = Page(
-        layout=PageLayout(width=210, height=297),
-        page_number=1
-    )
+    page = Page(layout=PageLayout(width=210, height=297), page_number=1)
 
     # Add various elements
-    page.layout.add_element(ImageData(
-        image_path="img1.jpg",
-        x=10, y=10,
-        width=100, height=75,
-        z_index=0
-    ))
+    page.layout.add_element(ImageData(image_path="img1.jpg", x=10, y=10, width=100, height=75, z_index=0))
 
-    page.layout.add_element(PlaceholderData(
-        x=120, y=10,
-        width=80, height=60,
-        z_index=1
-    ))
+    page.layout.add_element(PlaceholderData(x=120, y=10, width=80, height=60, z_index=1))
 
-    page.layout.add_element(TextBoxData(
-        x=10, y=100,
-        width=190, height=40,
-        text_content="Sample Text",
-        z_index=2
-    ))
+    page.layout.add_element(TextBoxData(x=10, y=100, width=190, height=40, text_content="Sample Text", z_index=2))
 
     return page
diff --git a/tests/test_alignment.py b/tests/test_alignment.py
index f660d61..31dc115 100755
--- a/tests/test_alignment.py
+++ b/tests/test_alignment.py
@@ -20,7 +20,7 @@ class TestAlignmentManager:
         """Test get_bounds with single element"""
         elem = ImageData(x=10, y=20, width=100, height=50)
         bounds = AlignmentManager.get_bounds([elem])
-        
+
         # min_x, min_y, max_x, max_y
         assert bounds == (10, 20, 110, 70)
 
@@ -29,9 +29,9 @@ class TestAlignmentManager:
         elem1 = ImageData(x=10, y=20, width=100, height=50)
         elem2 = ImageData(x=50, y=10, width=80, height=60)
         elem3 = ImageData(x=5, y=30, width=90, height=40)
-        
+
         bounds = AlignmentManager.get_bounds([elem1, elem2, elem3])
-        
+
         # min_x = 5, min_y = 10, max_x = 130 (50+80), max_y = 70 (10+60 or 20+50)
         assert bounds[0] == 5  # min_x
         assert bounds[1] == 10  # min_y
@@ -55,14 +55,14 @@ class TestAlignmentManager:
         elem1 = ImageData(x=50, y=20, width=100, height=50)
         elem2 = ImageData(x=30, y=40, width=80, height=60)
         elem3 = ImageData(x=70, y=60, width=90, height=40)
-        
+
         changes = AlignmentManager.align_left([elem1, elem2, elem3])
-        
+
         # All should align to x=30 (leftmost)
         assert elem1.position == (30, 20)
         assert elem2.position == (30, 40)
         assert elem3.position == (30, 60)
-        
+
         # Check undo information
         assert len(changes) == 3
         assert changes[0] == (elem1, (50, 20))
@@ -72,16 +72,16 @@ class TestAlignmentManager:
     def test_align_right_multiple_elements(self):
         """Test align_right with multiple elements"""
         elem1 = ImageData(x=50, y=20, width=100, height=50)  # right edge at 150
-        elem2 = ImageData(x=30, y=40, width=80, height=60)   # right edge at 110
-        elem3 = ImageData(x=70, y=60, width=90, height=40)   # right edge at 160
-        
+        elem2 = ImageData(x=30, y=40, width=80, height=60)  # right edge at 110
+        elem3 = ImageData(x=70, y=60, width=90, height=40)  # right edge at 160
+
         changes = AlignmentManager.align_right([elem1, elem2, elem3])
-        
+
         # All right edges should align to x=160 (rightmost)
         assert elem1.position[0] == 60  # 160 - 100
         assert elem2.position[0] == 80  # 160 - 80
         assert elem3.position[0] == 70  # 160 - 90
-        
+
         # Y positions should not change
         assert elem1.position[1] == 20
         assert elem2.position[1] == 40
@@ -92,14 +92,14 @@ class TestAlignmentManager:
         elem1 = ImageData(x=50, y=30, width=100, height=50)
         elem2 = ImageData(x=30, y=20, width=80, height=60)
         elem3 = ImageData(x=70, y=40, width=90, height=40)
-        
+
         changes = AlignmentManager.align_top([elem1, elem2, elem3])
-        
+
         # All should align to y=20 (topmost)
         assert elem1.position[1] == 20
         assert elem2.position[1] == 20
         assert elem3.position[1] == 20
-        
+
         # X positions should not change
         assert elem1.position[0] == 50
         assert elem2.position[0] == 30
@@ -108,16 +108,16 @@ class TestAlignmentManager:
     def test_align_bottom_multiple_elements(self):
         """Test align_bottom with multiple elements"""
         elem1 = ImageData(x=50, y=30, width=100, height=50)  # bottom at 80
-        elem2 = ImageData(x=30, y=20, width=80, height=60)   # bottom at 80
-        elem3 = ImageData(x=70, y=40, width=90, height=50)   # bottom at 90
-        
+        elem2 = ImageData(x=30, y=20, width=80, height=60)  # bottom at 80
+        elem3 = ImageData(x=70, y=40, width=90, height=50)  # bottom at 90
+
         changes = AlignmentManager.align_bottom([elem1, elem2, elem3])
-        
+
         # All bottom edges should align to y=90 (bottommost)
         assert elem1.position[1] == 40  # 90 - 50
         assert elem2.position[1] == 30  # 90 - 60
         assert elem3.position[1] == 40  # 90 - 50
-        
+
         # X positions should not change
         assert elem1.position[0] == 50
         assert elem2.position[0] == 30
@@ -125,18 +125,18 @@ class TestAlignmentManager:
 
     def test_align_horizontal_center_multiple_elements(self):
         """Test align_horizontal_center with multiple elements"""
-        elem1 = ImageData(x=50, y=20, width=100, height=50)   # center at 100
-        elem2 = ImageData(x=30, y=40, width=80, height=60)    # center at 70
-        elem3 = ImageData(x=70, y=60, width=60, height=40)    # center at 100
-        
+        elem1 = ImageData(x=50, y=20, width=100, height=50)  # center at 100
+        elem2 = ImageData(x=30, y=40, width=80, height=60)  # center at 70
+        elem3 = ImageData(x=70, y=60, width=60, height=40)  # center at 100
+
         changes = AlignmentManager.align_horizontal_center([elem1, elem2, elem3])
-        
+
         # Average center = (100 + 70 + 100) / 3 = 90
         # All elements should center at x=90
-        assert abs(elem1.position[0] + elem1.size[0]/2 - 90) < 0.01
-        assert abs(elem2.position[0] + elem2.size[0]/2 - 90) < 0.01
-        assert abs(elem3.position[0] + elem3.size[0]/2 - 90) < 0.01
-        
+        assert abs(elem1.position[0] + elem1.size[0] / 2 - 90) < 0.01
+        assert abs(elem2.position[0] + elem2.size[0] / 2 - 90) < 0.01
+        assert abs(elem3.position[0] + elem3.size[0] / 2 - 90) < 0.01
+
         # Y positions should not change
         assert elem1.position[1] == 20
         assert elem2.position[1] == 40
@@ -144,18 +144,18 @@ class TestAlignmentManager:
 
     def test_align_vertical_center_multiple_elements(self):
         """Test align_vertical_center with multiple elements"""
-        elem1 = ImageData(x=50, y=20, width=100, height=50)   # center at 45
-        elem2 = ImageData(x=30, y=40, width=80, height=60)    # center at 70
-        elem3 = ImageData(x=70, y=30, width=60, height=40)    # center at 50
-        
+        elem1 = ImageData(x=50, y=20, width=100, height=50)  # center at 45
+        elem2 = ImageData(x=30, y=40, width=80, height=60)  # center at 70
+        elem3 = ImageData(x=70, y=30, width=60, height=40)  # center at 50
+
         changes = AlignmentManager.align_vertical_center([elem1, elem2, elem3])
-        
+
         # Average center = (45 + 70 + 50) / 3 = 55
         # All elements should center at y=55
-        assert abs(elem1.position[1] + elem1.size[1]/2 - 55) < 0.01
-        assert abs(elem2.position[1] + elem2.size[1]/2 - 55) < 0.01
-        assert abs(elem3.position[1] + elem3.size[1]/2 - 55) < 0.01
-        
+        assert abs(elem1.position[1] + elem1.size[1] / 2 - 55) < 0.01
+        assert abs(elem2.position[1] + elem2.size[1] / 2 - 55) < 0.01
+        assert abs(elem3.position[1] + elem3.size[1] / 2 - 55) < 0.01
+
         # X positions should not change
         assert elem1.position[0] == 50
         assert elem2.position[0] == 30
@@ -178,14 +178,14 @@ class TestAlignmentManager:
         elem1 = ImageData(x=50, y=20, width=100, height=50)
         elem2 = ImageData(x=30, y=40, width=80, height=60)
         elem3 = ImageData(x=70, y=60, width=90, height=40)
-        
+
         changes = AlignmentManager.make_same_size([elem1, elem2, elem3])
-        
+
         # All should match elem1's size
         assert elem1.size == (100, 50)
         assert elem2.size == (100, 50)
         assert elem3.size == (100, 50)
-        
+
         # Check undo information (only elem2 and elem3 change)
         assert len(changes) == 2
         assert changes[0][0] == elem2
@@ -198,14 +198,14 @@ class TestAlignmentManager:
         elem1 = ImageData(x=50, y=20, width=100, height=50)
         elem2 = ImageData(x=30, y=40, width=80, height=60)
         elem3 = ImageData(x=70, y=60, width=90, height=40)
-        
+
         changes = AlignmentManager.make_same_width([elem1, elem2, elem3])
-        
+
         # All widths should match elem1
         assert elem1.size[0] == 100
         assert elem2.size[0] == 100
         assert elem3.size[0] == 100
-        
+
         # Heights should not change
         assert elem1.size[1] == 50
         assert elem2.size[1] == 60
@@ -216,14 +216,14 @@ class TestAlignmentManager:
         elem1 = ImageData(x=50, y=20, width=100, height=50)
         elem2 = ImageData(x=30, y=40, width=80, height=60)
         elem3 = ImageData(x=70, y=60, width=90, height=40)
-        
+
         changes = AlignmentManager.make_same_height([elem1, elem2, elem3])
-        
+
         # All heights should match elem1
         assert elem1.size[1] == 50
         assert elem2.size[1] == 50
         assert elem3.size[1] == 50
-        
+
         # Widths should not change
         assert elem1.size[0] == 100
         assert elem2.size[0] == 80
@@ -233,7 +233,7 @@ class TestAlignmentManager:
         """Test distribute_horizontally with less than 3 elements"""
         elem1 = ImageData(x=50, y=20, width=100, height=50)
         elem2 = ImageData(x=30, y=40, width=80, height=60)
-        
+
         changes = AlignmentManager.distribute_horizontally([elem1, elem2])
         assert changes == []
 
@@ -242,15 +242,15 @@ class TestAlignmentManager:
         elem1 = ImageData(x=0, y=20, width=100, height=50)
         elem2 = ImageData(x=50, y=40, width=80, height=60)
         elem3 = ImageData(x=200, y=60, width=90, height=40)
-        
+
         changes = AlignmentManager.distribute_horizontally([elem1, elem2, elem3])
-        
+
         # Elements should be distributed evenly by their left edges
         # min_x = 0, max_x = 200, span = 200
         # spacing = 200 / (3-1) = 100
         positions = [elem.position[0] for elem in [elem1, elem2, elem3]]
         sorted_positions = sorted(positions)
-        
+
         assert sorted_positions[0] == 0
         assert sorted_positions[1] == 100
         assert sorted_positions[2] == 200
@@ -260,15 +260,15 @@ class TestAlignmentManager:
         elem1 = ImageData(x=20, y=0, width=100, height=50)
         elem2 = ImageData(x=40, y=50, width=80, height=60)
         elem3 = ImageData(x=60, y=300, width=90, height=40)
-        
+
         changes = AlignmentManager.distribute_vertically([elem1, elem2, elem3])
-        
+
         # Elements should be distributed evenly by their top edges
         # min_y = 0, max_y = 300, span = 300
         # spacing = 300 / (3-1) = 150
         positions = [elem.position[1] for elem in [elem1, elem2, elem3]]
         sorted_positions = sorted(positions)
-        
+
         assert sorted_positions[0] == 0
         assert sorted_positions[1] == 150
         assert sorted_positions[2] == 300
@@ -277,7 +277,7 @@ class TestAlignmentManager:
         """Test space_horizontally with less than 3 elements"""
         elem1 = ImageData(x=50, y=20, width=100, height=50)
         elem2 = ImageData(x=200, y=40, width=80, height=60)
-        
+
         changes = AlignmentManager.space_horizontally([elem1, elem2])
         assert changes == []
 
@@ -286,17 +286,17 @@ class TestAlignmentManager:
         elem1 = ImageData(x=0, y=20, width=100, height=50)
         elem2 = ImageData(x=150, y=40, width=50, height=60)
         elem3 = ImageData(x=250, y=60, width=100, height=40)
-        
+
         changes = AlignmentManager.space_horizontally([elem1, elem2, elem3])
-        
+
         # Total width = 100 + 50 + 100 = 250
         # Span = 0 to 350 (250 + 100 from elem3)
         # Available space = 350 - 0 - 250 = 100
         # Spacing = 100 / (3-1) = 50
-        
+
         # After sorting by x: elem1 at 0, elem2 after 100+50=150, elem3 after 150+50+50=250
         sorted_elements = sorted([elem1, elem2, elem3], key=lambda e: e.position[0])
-        
+
         assert sorted_elements[0].position[0] == 0
         assert sorted_elements[1].position[0] == 150  # 0 + 100 + 50
         assert sorted_elements[2].position[0] == 250  # 150 + 50 + 50
@@ -306,17 +306,17 @@ class TestAlignmentManager:
         elem1 = ImageData(x=20, y=0, width=100, height=50)
         elem2 = ImageData(x=40, y=100, width=80, height=30)
         elem3 = ImageData(x=60, y=200, width=90, height=50)
-        
+
         changes = AlignmentManager.space_vertically([elem1, elem2, elem3])
-        
+
         # Total height = 50 + 30 + 50 = 130
         # Span = 0 to 250 (200 + 50 from elem3)
         # Available space = 250 - 0 - 130 = 120
         # Spacing = 120 / (3-1) = 60
-        
+
         # After sorting by y: elem1 at 0, elem2 after 50+60=110, elem3 after 110+30+60=200
         sorted_elements = sorted([elem1, elem2, elem3], key=lambda e: e.position[1])
-        
+
         assert sorted_elements[0].position[1] == 0
         assert sorted_elements[1].position[1] == 110  # 0 + 50 + 60
         assert sorted_elements[2].position[1] == 200  # 110 + 30 + 60
@@ -326,10 +326,10 @@ class TestAlignmentManager:
         elem1 = ImageData(x=50, y=20, width=100, height=50)
         elem2 = PlaceholderData(placeholder_type="image", x=30, y=40, width=80, height=60)
         elem3 = TextBoxData(text_content="Test", x=70, y=60, width=90, height=40)
-        
+
         # Test align_left
         changes = AlignmentManager.align_left([elem1, elem2, elem3])
-        
+
         assert elem1.position[0] == 30
         assert elem2.position[0] == 30
         assert elem3.position[0] == 30
@@ -339,23 +339,23 @@ class TestAlignmentManager:
         elem1 = ImageData(x=50, y=20, width=100, height=50)
         elem2 = ImageData(x=30, y=40, width=80, height=60)
         elem3 = ImageData(x=70, y=60, width=90, height=40)
-        
+
         # Test position changes
         changes = AlignmentManager.align_left([elem1, elem2, elem3])
-        
+
         for change in changes:
             assert len(change) == 2  # (element, old_position)
             assert isinstance(change[0], ImageData)
             assert isinstance(change[1], tuple)
             assert len(change[1]) == 2  # (x, y)
-        
+
         # Test size changes
         elem1 = ImageData(x=50, y=20, width=100, height=50)
         elem2 = ImageData(x=30, y=40, width=80, height=60)
         elem3 = ImageData(x=70, y=60, width=90, height=40)
-        
+
         changes = AlignmentManager.make_same_size([elem1, elem2, elem3])
-        
+
         for change in changes:
             assert len(change) == 3  # (element, old_position, old_size)
             assert isinstance(change[0], ImageData)
@@ -368,15 +368,15 @@ class TestAlignmentManager:
         """Test that alignment operations only change intended properties"""
         elem1 = ImageData(x=50, y=20, width=100, height=50, rotation=45, z_index=5)
         elem2 = ImageData(x=30, y=40, width=80, height=60, rotation=90, z_index=3)
-        
+
         AlignmentManager.align_left([elem1, elem2])
-        
+
         # Rotation and z_index should not change
         assert elem1.rotation == 45
         assert elem1.z_index == 5
         assert elem2.rotation == 90
         assert elem2.z_index == 3
-        
+
         # Heights should not change
         assert elem1.size[1] == 50
         assert elem2.size[1] == 60
@@ -387,10 +387,10 @@ class TestAlignmentManager:
         elem3 = ImageData(x=200, y=60, width=90, height=40)
         elem1 = ImageData(x=0, y=20, width=100, height=50)
         elem2 = ImageData(x=100, y=40, width=80, height=60)
-        
+
         # Pass in random order
         changes = AlignmentManager.distribute_horizontally([elem3, elem1, elem2])
-        
+
         # Should still distribute correctly
         positions = sorted([elem1.position[0], elem2.position[0], elem3.position[0]])
         assert positions[0] == 0
@@ -402,21 +402,21 @@ class TestAlignmentManager:
         elem1 = ImageData(x=0, y=0, width=50, height=50)
         elem2 = ImageData(x=100, y=0, width=100, height=50)
         elem3 = ImageData(x=250, y=0, width=75, height=50)
-        
+
         changes = AlignmentManager.space_horizontally([elem1, elem2, elem3])
-        
+
         # Calculate expected spacing
         # Total width = 50 + 100 + 75 = 225
         # rightmost edge = 250 + 75 = 325
         # Available space = 325 - 0 - 225 = 100
         # Spacing = 100 / 2 = 50
-        
+
         sorted_elements = sorted([elem1, elem2, elem3], key=lambda e: e.position[0])
-        
+
         # Verify spacing between elements is equal
         gap1 = sorted_elements[1].position[0] - (sorted_elements[0].position[0] + sorted_elements[0].size[0])
         gap2 = sorted_elements[2].position[0] - (sorted_elements[1].position[0] + sorted_elements[1].size[0])
-        
+
         assert abs(gap1 - 50) < 0.01
         assert abs(gap2 - 50) < 0.01
 
@@ -452,7 +452,7 @@ class TestAlignmentManager:
         assert len(changes) == 1
         assert changes[0][0] == elem
         assert changes[0][1] == (100, 80)  # old position
-        assert changes[0][2] == (20, 15)   # old size
+        assert changes[0][2] == (20, 15)  # old size
 
     def test_maximize_pattern_two_elements_horizontal(self):
         """Test maximize_pattern with two elements side by side"""
@@ -469,11 +469,11 @@ class TestAlignmentManager:
         # Elements should not overlap (min_gap = 2.0)
         gap_x = max(
             elem2.position[0] - (elem1.position[0] + elem1.size[0]),
-            elem1.position[0] - (elem2.position[0] + elem2.size[0])
+            elem1.position[0] - (elem2.position[0] + elem2.size[0]),
         )
         gap_y = max(
             elem2.position[1] - (elem1.position[1] + elem1.size[1]),
-            elem1.position[1] - (elem2.position[1] + elem2.size[1])
+            elem1.position[1] - (elem2.position[1] + elem2.size[1]),
         )
 
         # Either horizontal or vertical gap should be >= min_gap
@@ -510,11 +510,11 @@ class TestAlignmentManager:
                 # Calculate gaps between rectangles
                 gap_x = max(
                     elem_b.position[0] - (elem_a.position[0] + elem_a.size[0]),
-                    elem_a.position[0] - (elem_b.position[0] + elem_b.size[0])
+                    elem_a.position[0] - (elem_b.position[0] + elem_b.size[0]),
                 )
                 gap_y = max(
                     elem_b.position[1] - (elem_a.position[1] + elem_a.size[1]),
-                    elem_a.position[1] - (elem_b.position[1] + elem_b.size[1])
+                    elem_a.position[1] - (elem_b.position[1] + elem_b.size[1]),
                 )
 
                 # At least one gap should be >= min_gap
@@ -564,11 +564,7 @@ class TestAlignmentManager:
         elem4 = ImageData(x=140, y=90, width=10, height=10)
         page_size = (160, 110)
 
-        changes = AlignmentManager.maximize_pattern(
-            [elem1, elem2, elem3, elem4],
-            page_size,
-            min_gap=2.0
-        )
+        changes = AlignmentManager.maximize_pattern([elem1, elem2, elem3, elem4], page_size, min_gap=2.0)
 
         # All elements should grow
         for elem in [elem1, elem2, elem3, elem4]:
@@ -584,11 +580,11 @@ class TestAlignmentManager:
 
                 gap_x = max(
                     elem_b.position[0] - (elem_a.position[0] + elem_a.size[0]),
-                    elem_a.position[0] - (elem_b.position[0] + elem_b.size[0])
+                    elem_a.position[0] - (elem_b.position[0] + elem_b.size[0]),
                 )
                 gap_y = max(
                     elem_b.position[1] - (elem_a.position[1] + elem_a.size[1]),
-                    elem_a.position[1] - (elem_b.position[1] + elem_b.size[1])
+                    elem_a.position[1] - (elem_b.position[1] + elem_b.size[1]),
                 )
 
                 assert gap_x >= 2.0 or gap_y >= 2.0
diff --git a/tests/test_alignment_ops_mixin.py b/tests/test_alignment_ops_mixin.py
index 86543d1..d9fb28c 100755
--- a/tests/test_alignment_ops_mixin.py
+++ b/tests/test_alignment_ops_mixin.py
@@ -81,7 +81,7 @@ class TestGetSelectedElementsList:
 class TestAlignLeft:
     """Test align_left method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager")
     def test_align_left_success(self, mock_manager, qtbot):
         """Test aligning elements to the left"""
         window = TestAlignmentWindow()
@@ -93,10 +93,7 @@ class TestAlignLeft:
         window.gl_widget.selected_elements = {element1, element2}
 
         # Mock AlignmentManager to return changes
-        mock_manager.align_left.return_value = [
-            (element1, (100, 0)),
-            (element2, (200, 100))
-        ]
+        mock_manager.align_left.return_value = [(element1, (100, 0)), (element2, (200, 100))]
 
         window.align_left()
 
@@ -106,7 +103,7 @@ class TestAlignLeft:
         assert "aligned" in window._status_message.lower()
         assert "left" in window._status_message.lower()
 
-    @patch('pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager")
     def test_align_left_no_changes(self, mock_manager, qtbot):
         """Test align left when no changes needed"""
         window = TestAlignmentWindow()
@@ -143,7 +140,7 @@ class TestAlignLeft:
 class TestAlignRight:
     """Test align_right method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager")
     def test_align_right_success(self, mock_manager, qtbot):
         """Test aligning elements to the right"""
         window = TestAlignmentWindow()
@@ -154,10 +151,7 @@ class TestAlignRight:
 
         window.gl_widget.selected_elements = {element1, element2}
 
-        mock_manager.align_right.return_value = [
-            (element1, (100, 0)),
-            (element2, (200, 100))
-        ]
+        mock_manager.align_right.return_value = [(element1, (100, 0)), (element2, (200, 100))]
 
         window.align_right()
 
@@ -169,7 +163,7 @@ class TestAlignRight:
 class TestAlignTop:
     """Test align_top method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager")
     def test_align_top_success(self, mock_manager, qtbot):
         """Test aligning elements to the top"""
         window = TestAlignmentWindow()
@@ -180,10 +174,7 @@ class TestAlignTop:
 
         window.gl_widget.selected_elements = {element1, element2}
 
-        mock_manager.align_top.return_value = [
-            (element1, (0, 50)),
-            (element2, (100, 100))
-        ]
+        mock_manager.align_top.return_value = [(element1, (0, 50)), (element2, (100, 100))]
 
         window.align_top()
 
@@ -195,7 +186,7 @@ class TestAlignTop:
 class TestAlignBottom:
     """Test align_bottom method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager")
     def test_align_bottom_success(self, mock_manager, qtbot):
         """Test aligning elements to the bottom"""
         window = TestAlignmentWindow()
@@ -206,10 +197,7 @@ class TestAlignBottom:
 
         window.gl_widget.selected_elements = {element1, element2}
 
-        mock_manager.align_bottom.return_value = [
-            (element1, (0, 50)),
-            (element2, (100, 100))
-        ]
+        mock_manager.align_bottom.return_value = [(element1, (0, 50)), (element2, (100, 100))]
 
         window.align_bottom()
 
@@ -221,7 +209,7 @@ class TestAlignBottom:
 class TestAlignHorizontalCenter:
     """Test align_horizontal_center method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager")
     def test_align_horizontal_center_success(self, mock_manager, qtbot):
         """Test aligning elements to horizontal center"""
         window = TestAlignmentWindow()
@@ -232,10 +220,7 @@ class TestAlignHorizontalCenter:
 
         window.gl_widget.selected_elements = {element1, element2}
 
-        mock_manager.align_horizontal_center.return_value = [
-            (element1, (0, 0)),
-            (element2, (200, 100))
-        ]
+        mock_manager.align_horizontal_center.return_value = [(element1, (0, 0)), (element2, (200, 100))]
 
         window.align_horizontal_center()
 
@@ -247,7 +232,7 @@ class TestAlignHorizontalCenter:
 class TestAlignVerticalCenter:
     """Test align_vertical_center method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager")
     def test_align_vertical_center_success(self, mock_manager, qtbot):
         """Test aligning elements to vertical center"""
         window = TestAlignmentWindow()
@@ -258,10 +243,7 @@ class TestAlignVerticalCenter:
 
         window.gl_widget.selected_elements = {element1, element2}
 
-        mock_manager.align_vertical_center.return_value = [
-            (element1, (0, 0)),
-            (element2, (100, 200))
-        ]
+        mock_manager.align_vertical_center.return_value = [(element1, (0, 0)), (element2, (100, 200))]
 
         window.align_vertical_center()
 
@@ -273,7 +255,7 @@ class TestAlignVerticalCenter:
 class TestAlignmentCommandPattern:
     """Test alignment operations with command pattern for undo/redo"""
 
-    @patch('pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager")
     def test_alignment_creates_command(self, mock_manager, qtbot):
         """Test that alignment creates a command for undo"""
         window = TestAlignmentWindow()
@@ -284,10 +266,7 @@ class TestAlignmentCommandPattern:
 
         window.gl_widget.selected_elements = {element1, element2}
 
-        mock_manager.align_left.return_value = [
-            (element1, (100, 0)),
-            (element2, (200, 100))
-        ]
+        mock_manager.align_left.return_value = [(element1, (100, 0)), (element2, (200, 100))]
 
         # Should have no commands initially
         assert not window.project.history.can_undo()
@@ -297,7 +276,7 @@ class TestAlignmentCommandPattern:
         # Should have created a command
         assert window.project.history.can_undo()
 
-    @patch('pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.alignment_ops.AlignmentManager")
     def test_alignment_undo_redo(self, mock_manager, qtbot):
         """Test that alignment can be undone and redone"""
         window = TestAlignmentWindow()
@@ -309,10 +288,7 @@ class TestAlignmentCommandPattern:
         window.gl_widget.selected_elements = {element1, element2}
 
         # Mock alignment to return changes (command will handle actual moves)
-        mock_manager.align_top.return_value = [
-            (element1, (100, 0)),
-            (element2, (200, 100))
-        ]
+        mock_manager.align_top.return_value = [(element1, (100, 0)), (element2, (200, 100))]
 
         # Execute alignment - command created
         window.align_top()
diff --git a/tests/test_asset_drop_mixin.py b/tests/test_asset_drop_mixin.py
index 83e3f66..ab7b4d8 100755
--- a/tests/test_asset_drop_mixin.py
+++ b/tests/test_asset_drop_mixin.py
@@ -28,8 +28,8 @@ class TestAssetDropWidget(AssetDropMixin, AssetPathMixin, PageNavigationMixin, V
     def _get_project_folder(self):
         """Override to access project via window mock"""
         main_window = self.window()
-        if hasattr(main_window, 'project') and main_window.project:
-            return getattr(main_window.project, 'folder_path', None)
+        if hasattr(main_window, "project") and main_window.project:
+            return getattr(main_window.project, "folder_path", None)
         return None
 
 
@@ -43,7 +43,7 @@ class TestAssetDropInitialization:
 
         # Should accept drops (set in GLWidget.__init__)
         # This is a property of the widget, not the mixin
-        assert hasattr(widget, 'acceptDrops')
+        assert hasattr(widget, "acceptDrops")
 
 
 class TestDragEnterEvent:
@@ -141,7 +141,7 @@ class TestDragMoveEvent:
 class TestDropEvent:
     """Test dropEvent method"""
 
-    @patch('pyPhotoAlbum.mixins.asset_drop.AddElementCommand')
+    @patch("pyPhotoAlbum.mixins.asset_drop.AddElementCommand")
     def test_drop_creates_image_element(self, mock_cmd_class, qtbot):
         """Test dropping image file creates ImageData element"""
         widget = TestAssetDropWidget()
@@ -239,7 +239,7 @@ class TestDropEvent:
 
         # Create a real test image file
         test_image = tmp_path / "test_image.jpg"
-        test_image.write_bytes(b'\xFF\xD8\xFF\xE0' + b'\x00' * 100)  # Minimal JPEG header
+        test_image.write_bytes(b"\xff\xd8\xff\xe0" + b"\x00" * 100)  # Minimal JPEG header
 
         # Setup project with page containing placeholder
         mock_window = Mock()
@@ -248,6 +248,7 @@ class TestDropEvent:
         page = Page(layout=PageLayout(width=210, height=297), page_number=1)
 
         from pyPhotoAlbum.models import PlaceholderData
+
         placeholder = PlaceholderData(x=100, y=100, width=200, height=150)
         page.layout.elements.append(placeholder)
 
@@ -280,7 +281,7 @@ class TestDropEvent:
         # Image path should now be in assets folder (imported)
         assert page.layout.elements[0].image_path.startswith("assets/")
 
-    @patch('pyPhotoAlbum.mixins.asset_drop.AddElementCommand')
+    @patch("pyPhotoAlbum.mixins.asset_drop.AddElementCommand")
     def test_drop_multiple_files(self, mock_cmd_class, qtbot):
         """Test dropping first image from multiple files"""
         widget = TestAssetDropWidget()
@@ -311,11 +312,13 @@ class TestDropEvent:
 
         # Create drop event with multiple files (only first is used)
         mime_data = QMimeData()
-        mime_data.setUrls([
-            QUrl.fromLocalFile("/path/to/image1.jpg"),
-            QUrl.fromLocalFile("/path/to/image2.png"),
-            QUrl.fromLocalFile("/path/to/image3.jpg")
-        ])
+        mime_data.setUrls(
+            [
+                QUrl.fromLocalFile("/path/to/image1.jpg"),
+                QUrl.fromLocalFile("/path/to/image2.png"),
+                QUrl.fromLocalFile("/path/to/image3.jpg"),
+            ]
+        )
 
         event = Mock()
         event.mimeData = Mock(return_value=mime_data)
@@ -364,7 +367,7 @@ class TestDropEvent:
 
         # Create a real test image file
         test_image = tmp_path / "new_image.jpg"
-        test_image.write_bytes(b'\xFF\xD8\xFF\xE0' + b'\x00' * 100)
+        test_image.write_bytes(b"\xff\xd8\xff\xe0" + b"\x00" * 100)
 
         # Setup project with page containing existing ImageData
         mock_window = Mock()
@@ -372,10 +375,7 @@ class TestDropEvent:
         mock_window.project.working_dpi = 96
         page = Page(layout=PageLayout(width=210, height=297), page_number=1)
 
-        existing_image = ImageData(
-            image_path="assets/old_image.jpg",
-            x=100, y=100, width=200, height=150
-        )
+        existing_image = ImageData(image_path="assets/old_image.jpg", x=100, y=100, width=200, height=150)
         page.layout.elements.append(existing_image)
         mock_window.project.pages = [page]
 
@@ -407,24 +407,19 @@ class TestDropEvent:
         widget.update = Mock()
 
         test_image = tmp_path / "test.jpg"
-        test_image.write_bytes(b'\xFF\xD8\xFF\xE0' + b'\x00' * 100)
+        test_image.write_bytes(b"\xff\xd8\xff\xe0" + b"\x00" * 100)
 
         mock_window = Mock()
         mock_window.project = Project(name="Test")
         page = Page(layout=PageLayout(width=210, height=297), page_number=1)
 
-        existing_image = ImageData(
-            image_path="assets/old.jpg",
-            x=100, y=100, width=200, height=150
-        )
+        existing_image = ImageData(image_path="assets/old.jpg", x=100, y=100, width=200, height=150)
         page.layout.elements.append(existing_image)
         mock_window.project.pages = [page]
 
         # Mock asset manager to raise exception
         mock_window.project.asset_manager = Mock()
-        mock_window.project.asset_manager.import_asset = Mock(
-            side_effect=Exception("Import failed")
-        )
+        mock_window.project.asset_manager.import_asset = Mock(side_effect=Exception("Import failed"))
 
         widget.window = Mock(return_value=mock_window)
         widget._get_element_at = Mock(return_value=existing_image)
@@ -454,7 +449,7 @@ class TestDropEvent:
 
         # Create a corrupted/invalid image file
         corrupted_image = tmp_path / "corrupted.jpg"
-        corrupted_image.write_bytes(b'not a valid image')
+        corrupted_image.write_bytes(b"not a valid image")
 
         mock_window = Mock()
         mock_window.project = Project(name="Test")
@@ -488,7 +483,8 @@ class TestDropEvent:
         # Should use default dimensions (200, 150) from _calculate_image_dimensions
         # Check that AddElementCommand was called with an ImageData
         from pyPhotoAlbum.commands import AddElementCommand
-        with patch('pyPhotoAlbum.mixins.asset_drop.AddElementCommand') as mock_cmd:
+
+        with patch("pyPhotoAlbum.mixins.asset_drop.AddElementCommand") as mock_cmd:
             # Re-run to check the call
             widget.dropEvent(event)
             assert mock_cmd.called
@@ -527,10 +523,7 @@ class TestExtractImagePathEdgeCases:
         widget.update = Mock()
 
         mime_data = QMimeData()
-        mime_data.setUrls([
-            QUrl.fromLocalFile("/path/to/document.pdf"),
-            QUrl.fromLocalFile("/path/to/file.txt")
-        ])
+        mime_data.setUrls([QUrl.fromLocalFile("/path/to/document.pdf"), QUrl.fromLocalFile("/path/to/file.txt")])
 
         event = Mock()
         event.mimeData = Mock(return_value=mime_data)
@@ -576,7 +569,7 @@ class TestPlaceholderReplacementEdgeCases:
         widget.update = Mock()
 
         test_image = tmp_path / "test.jpg"
-        test_image.write_bytes(b'\xFF\xD8\xFF\xE0' + b'\x00' * 100)
+        test_image.write_bytes(b"\xff\xd8\xff\xe0" + b"\x00" * 100)
 
         # Setup project WITHOUT pages
         mock_window = Mock()
@@ -585,6 +578,7 @@ class TestPlaceholderReplacementEdgeCases:
         mock_window.project.pages = []  # Empty pages list
 
         from pyPhotoAlbum.models import PlaceholderData
+
         placeholder = PlaceholderData(x=100, y=100, width=200, height=150)
 
         mock_window.project.asset_manager = Mock()
diff --git a/tests/test_asset_path_mixin.py b/tests/test_asset_path_mixin.py
new file mode 100644
index 0000000..64def84
--- /dev/null
+++ b/tests/test_asset_path_mixin.py
@@ -0,0 +1,183 @@
+"""
+Tests for asset_path mixin module
+"""
+
+import pytest
+import os
+from unittest.mock import Mock
+
+
+class TestAssetPathMixin:
+    """Tests for AssetPathMixin class"""
+
+    def test_resolve_asset_path_empty_path(self, tmp_path):
+        """Test resolve_asset_path with empty path returns None"""
+        from pyPhotoAlbum.mixins.asset_path import AssetPathMixin
+
+        class TestClass(AssetPathMixin):
+            def __init__(self):
+                self.project = Mock()
+                self.project.folder_path = str(tmp_path)
+
+        obj = TestClass()
+        assert obj.resolve_asset_path("") is None
+        assert obj.resolve_asset_path(None) is None
+
+    def test_resolve_asset_path_absolute_exists(self, tmp_path):
+        """Test resolve_asset_path with existing absolute path"""
+        from pyPhotoAlbum.mixins.asset_path import AssetPathMixin
+
+        # Create a test file
+        test_file = tmp_path / "test_image.jpg"
+        test_file.write_text("test")
+
+        class TestClass(AssetPathMixin):
+            def __init__(self):
+                self.project = Mock()
+                self.project.folder_path = str(tmp_path)
+
+        obj = TestClass()
+        result = obj.resolve_asset_path(str(test_file))
+
+        assert result == str(test_file)
+
+    def test_resolve_asset_path_absolute_not_exists(self, tmp_path):
+        """Test resolve_asset_path with non-existing absolute path"""
+        from pyPhotoAlbum.mixins.asset_path import AssetPathMixin
+
+        class TestClass(AssetPathMixin):
+            def __init__(self):
+                self.project = Mock()
+                self.project.folder_path = str(tmp_path)
+
+        obj = TestClass()
+        result = obj.resolve_asset_path("/nonexistent/path/image.jpg")
+
+        assert result is None
+
+    def test_resolve_asset_path_relative_exists(self, tmp_path):
+        """Test resolve_asset_path with existing relative path"""
+        from pyPhotoAlbum.mixins.asset_path import AssetPathMixin
+
+        # Create assets folder and test file
+        assets_dir = tmp_path / "assets"
+        assets_dir.mkdir()
+        test_file = assets_dir / "photo.jpg"
+        test_file.write_text("test")
+
+        class TestClass(AssetPathMixin):
+            def __init__(self):
+                self.project = Mock()
+                self.project.folder_path = str(tmp_path)
+
+        obj = TestClass()
+        result = obj.resolve_asset_path("assets/photo.jpg")
+
+        assert result == str(test_file)
+
+    def test_resolve_asset_path_relative_not_exists(self, tmp_path):
+        """Test resolve_asset_path with non-existing relative path"""
+        from pyPhotoAlbum.mixins.asset_path import AssetPathMixin
+
+        class TestClass(AssetPathMixin):
+            def __init__(self):
+                self.project = Mock()
+                self.project.folder_path = str(tmp_path)
+
+        obj = TestClass()
+        result = obj.resolve_asset_path("assets/nonexistent.jpg")
+
+        assert result is None
+
+    def test_resolve_asset_path_no_project_folder(self):
+        """Test resolve_asset_path when project folder is not available"""
+        from pyPhotoAlbum.mixins.asset_path import AssetPathMixin
+
+        class TestClass(AssetPathMixin):
+            def __init__(self):
+                self.project = None
+
+        obj = TestClass()
+        result = obj.resolve_asset_path("assets/photo.jpg")
+
+        assert result is None
+
+    def test_get_asset_full_path_with_project(self, tmp_path):
+        """Test get_asset_full_path returns correct path"""
+        from pyPhotoAlbum.mixins.asset_path import AssetPathMixin
+
+        class TestClass(AssetPathMixin):
+            def __init__(self):
+                self.project = Mock()
+                self.project.folder_path = str(tmp_path)
+
+        obj = TestClass()
+        result = obj.get_asset_full_path("assets/photo.jpg")
+
+        expected = os.path.join(str(tmp_path), "assets/photo.jpg")
+        assert result == expected
+
+    def test_get_asset_full_path_no_project(self):
+        """Test get_asset_full_path without project returns None"""
+        from pyPhotoAlbum.mixins.asset_path import AssetPathMixin
+
+        class TestClass(AssetPathMixin):
+            def __init__(self):
+                self.project = None
+
+        obj = TestClass()
+        result = obj.get_asset_full_path("assets/photo.jpg")
+
+        assert result is None
+
+    def test_get_asset_full_path_empty_path(self, tmp_path):
+        """Test get_asset_full_path with empty path returns None"""
+        from pyPhotoAlbum.mixins.asset_path import AssetPathMixin
+
+        class TestClass(AssetPathMixin):
+            def __init__(self):
+                self.project = Mock()
+                self.project.folder_path = str(tmp_path)
+
+        obj = TestClass()
+        assert obj.get_asset_full_path("") is None
+        assert obj.get_asset_full_path(None) is None
+
+    def test_get_project_folder_with_project(self, tmp_path):
+        """Test _get_project_folder returns project folder"""
+        from pyPhotoAlbum.mixins.asset_path import AssetPathMixin
+
+        class TestClass(AssetPathMixin):
+            def __init__(self):
+                self.project = Mock()
+                self.project.folder_path = str(tmp_path)
+
+        obj = TestClass()
+        result = obj._get_project_folder()
+
+        assert result == str(tmp_path)
+
+    def test_get_project_folder_no_project(self):
+        """Test _get_project_folder without project returns None"""
+        from pyPhotoAlbum.mixins.asset_path import AssetPathMixin
+
+        class TestClass(AssetPathMixin):
+            pass
+
+        obj = TestClass()
+        result = obj._get_project_folder()
+
+        assert result is None
+
+    def test_get_project_folder_project_without_folder_path(self):
+        """Test _get_project_folder with project missing folder_path"""
+        from pyPhotoAlbum.mixins.asset_path import AssetPathMixin
+
+        class TestClass(AssetPathMixin):
+            def __init__(self):
+                self.project = Mock(spec=[])  # No folder_path attribute
+
+        obj = TestClass()
+        result = obj._get_project_folder()
+
+        assert result is None
diff --git a/tests/test_async_loading_mixin.py b/tests/test_async_loading_mixin.py
new file mode 100644
index 0000000..e40f307
--- /dev/null
+++ b/tests/test_async_loading_mixin.py
@@ -0,0 +1,635 @@
+"""
+Tests for async_loading mixin module
+"""
+
+import pytest
+from pathlib import Path
+from unittest.mock import Mock, MagicMock, patch, PropertyMock
+
+
+class TestAsyncLoadingMixinInit:
+    """Tests for AsyncLoadingMixin initialization"""
+
+    def test_init_async_loading_creates_cache(self):
+        """Test that _init_async_loading creates image cache"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        with (
+            patch("pyPhotoAlbum.mixins.async_loading.ImageCache") as mock_cache,
+            patch("pyPhotoAlbum.mixins.async_loading.AsyncImageLoader") as mock_loader,
+            patch("pyPhotoAlbum.mixins.async_loading.AsyncPDFGenerator") as mock_pdf,
+        ):
+
+            mock_loader_instance = Mock()
+            mock_loader.return_value = mock_loader_instance
+            mock_pdf_instance = Mock()
+            mock_pdf.return_value = mock_pdf_instance
+
+            class TestClass(AsyncLoadingMixin):
+                pass
+
+            obj = TestClass()
+            obj._init_async_loading()
+
+            mock_cache.assert_called_once_with(max_memory_mb=512)
+            assert hasattr(obj, "image_cache")
+
+    def test_init_async_loading_creates_image_loader(self):
+        """Test that _init_async_loading creates async image loader"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        with (
+            patch("pyPhotoAlbum.mixins.async_loading.ImageCache") as mock_cache,
+            patch("pyPhotoAlbum.mixins.async_loading.AsyncImageLoader") as mock_loader,
+            patch("pyPhotoAlbum.mixins.async_loading.AsyncPDFGenerator") as mock_pdf,
+        ):
+
+            mock_loader_instance = Mock()
+            mock_loader.return_value = mock_loader_instance
+            mock_pdf_instance = Mock()
+            mock_pdf.return_value = mock_pdf_instance
+
+            class TestClass(AsyncLoadingMixin):
+                pass
+
+            obj = TestClass()
+            obj._init_async_loading()
+
+            mock_loader.assert_called_once()
+            assert hasattr(obj, "async_image_loader")
+            mock_loader_instance.start.assert_called_once()
+
+    def test_init_async_loading_creates_pdf_generator(self):
+        """Test that _init_async_loading creates async PDF generator"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        with (
+            patch("pyPhotoAlbum.mixins.async_loading.ImageCache") as mock_cache,
+            patch("pyPhotoAlbum.mixins.async_loading.AsyncImageLoader") as mock_loader,
+            patch("pyPhotoAlbum.mixins.async_loading.AsyncPDFGenerator") as mock_pdf,
+        ):
+
+            mock_loader_instance = Mock()
+            mock_loader.return_value = mock_loader_instance
+            mock_pdf_instance = Mock()
+            mock_pdf.return_value = mock_pdf_instance
+
+            class TestClass(AsyncLoadingMixin):
+                pass
+
+            obj = TestClass()
+            obj._init_async_loading()
+
+            mock_pdf.assert_called_once()
+            assert hasattr(obj, "async_pdf_generator")
+            mock_pdf_instance.start.assert_called_once()
+
+
+class TestAsyncLoadingMixinCleanup:
+    """Tests for AsyncLoadingMixin cleanup"""
+
+    def test_cleanup_stops_image_loader(self):
+        """Test that _cleanup_async_loading stops image loader"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        obj.async_image_loader = Mock()
+        obj.async_pdf_generator = Mock()
+        obj.image_cache = Mock()
+
+        obj._cleanup_async_loading()
+
+        obj.async_image_loader.stop.assert_called_once()
+
+    def test_cleanup_stops_pdf_generator(self):
+        """Test that _cleanup_async_loading stops PDF generator"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        obj.async_image_loader = Mock()
+        obj.async_pdf_generator = Mock()
+        obj.image_cache = Mock()
+
+        obj._cleanup_async_loading()
+
+        obj.async_pdf_generator.stop.assert_called_once()
+
+    def test_cleanup_clears_cache(self):
+        """Test that _cleanup_async_loading clears image cache"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        obj.async_image_loader = Mock()
+        obj.async_pdf_generator = Mock()
+        obj.image_cache = Mock()
+
+        obj._cleanup_async_loading()
+
+        obj.image_cache.clear.assert_called_once()
+
+    def test_cleanup_handles_missing_components(self):
+        """Test that _cleanup_async_loading handles missing components gracefully"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        # Don't set any async components
+
+        # Should not raise
+        obj._cleanup_async_loading()
+
+
+class TestOnImageLoaded:
+    """Tests for _on_image_loaded callback"""
+
+    def test_on_image_loaded_calls_element_callback(self):
+        """Test that _on_image_loaded calls element's callback"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            def update(self):
+                pass
+
+        obj = TestClass()
+
+        mock_image = Mock()
+        mock_user_data = Mock()
+        mock_user_data._on_async_image_loaded = Mock()
+
+        obj._on_image_loaded(Path("/test/image.jpg"), mock_image, mock_user_data)
+
+        mock_user_data._on_async_image_loaded.assert_called_once_with(mock_image)
+
+    def test_on_image_loaded_triggers_update(self):
+        """Test that _on_image_loaded triggers widget update"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            def __init__(self):
+                self.update_called = False
+
+            def update(self):
+                self.update_called = True
+
+        obj = TestClass()
+
+        obj._on_image_loaded(Path("/test/image.jpg"), Mock(), None)
+
+        assert obj.update_called
+
+    def test_on_image_loaded_handles_none_user_data(self):
+        """Test that _on_image_loaded handles None user_data"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            def update(self):
+                pass
+
+        obj = TestClass()
+
+        # Should not raise
+        obj._on_image_loaded(Path("/test/image.jpg"), Mock(), None)
+
+
+class TestOnImageLoadFailed:
+    """Tests for _on_image_load_failed callback"""
+
+    def test_on_image_load_failed_calls_element_callback(self):
+        """Test that _on_image_load_failed calls element's callback"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+
+        mock_user_data = Mock()
+        mock_user_data._on_async_image_load_failed = Mock()
+
+        obj._on_image_load_failed(Path("/test/image.jpg"), "Error message", mock_user_data)
+
+        mock_user_data._on_async_image_load_failed.assert_called_once_with("Error message")
+
+    def test_on_image_load_failed_handles_none_user_data(self):
+        """Test that _on_image_load_failed handles None user_data"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+
+        # Should not raise
+        obj._on_image_load_failed(Path("/test/image.jpg"), "Error", None)
+
+
+class TestOnPdfProgress:
+    """Tests for _on_pdf_progress callback"""
+
+    def test_on_pdf_progress_updates_dialog(self):
+        """Test that _on_pdf_progress updates progress dialog"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        obj._pdf_progress_dialog = Mock()
+
+        obj._on_pdf_progress(5, 10, "Processing page 5")
+
+        obj._pdf_progress_dialog.setValue.assert_called_once_with(5)
+        obj._pdf_progress_dialog.setLabelText.assert_called_once_with("Processing page 5")
+
+    def test_on_pdf_progress_handles_no_dialog(self):
+        """Test that _on_pdf_progress handles missing dialog"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        # No _pdf_progress_dialog attribute
+
+        # Should not raise
+        obj._on_pdf_progress(5, 10, "Processing")
+
+
+class TestOnPdfComplete:
+    """Tests for _on_pdf_complete callback"""
+
+    def test_on_pdf_complete_closes_dialog(self):
+        """Test that _on_pdf_complete closes progress dialog"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            def window(self):
+                return Mock(spec=[])
+
+        obj = TestClass()
+        mock_dialog = Mock()
+        obj._pdf_progress_dialog = mock_dialog
+
+        obj._on_pdf_complete(True, [])
+
+        mock_dialog.close.assert_called_once()
+        assert obj._pdf_progress_dialog is None
+
+    def test_on_pdf_complete_shows_success_status(self):
+        """Test that _on_pdf_complete shows success status"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        mock_main_window = Mock()
+
+        class TestClass(AsyncLoadingMixin):
+            def window(self):
+                return mock_main_window
+
+        obj = TestClass()
+
+        obj._on_pdf_complete(True, [])
+
+        mock_main_window.show_status.assert_called_once()
+        call_args = mock_main_window.show_status.call_args[0]
+        assert "successfully" in call_args[0]
+
+    def test_on_pdf_complete_shows_warnings(self):
+        """Test that _on_pdf_complete shows warning count"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        mock_main_window = Mock()
+
+        class TestClass(AsyncLoadingMixin):
+            def window(self):
+                return mock_main_window
+
+        obj = TestClass()
+
+        obj._on_pdf_complete(True, ["warning1", "warning2"])
+
+        mock_main_window.show_status.assert_called_once()
+        call_args = mock_main_window.show_status.call_args[0]
+        assert "2 warnings" in call_args[0]
+
+    def test_on_pdf_complete_shows_failure_status(self):
+        """Test that _on_pdf_complete shows failure status"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        mock_main_window = Mock()
+
+        class TestClass(AsyncLoadingMixin):
+            def window(self):
+                return mock_main_window
+
+        obj = TestClass()
+
+        obj._on_pdf_complete(False, [])
+
+        mock_main_window.show_status.assert_called_once()
+        call_args = mock_main_window.show_status.call_args[0]
+        assert "failed" in call_args[0]
+
+
+class TestOnPdfFailed:
+    """Tests for _on_pdf_failed callback"""
+
+    def test_on_pdf_failed_closes_dialog(self):
+        """Test that _on_pdf_failed closes progress dialog"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            def window(self):
+                return Mock(spec=[])
+
+        obj = TestClass()
+        mock_dialog = Mock()
+        obj._pdf_progress_dialog = mock_dialog
+
+        obj._on_pdf_failed("Error occurred")
+
+        mock_dialog.close.assert_called_once()
+        assert obj._pdf_progress_dialog is None
+
+    def test_on_pdf_failed_shows_error_status(self):
+        """Test that _on_pdf_failed shows error status"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        mock_main_window = Mock()
+
+        class TestClass(AsyncLoadingMixin):
+            def window(self):
+                return mock_main_window
+
+        obj = TestClass()
+
+        obj._on_pdf_failed("Something went wrong")
+
+        mock_main_window.show_status.assert_called_once()
+        call_args = mock_main_window.show_status.call_args[0]
+        assert "failed" in call_args[0]
+        assert "Something went wrong" in call_args[0]
+
+
+class TestRequestImageLoad:
+    """Tests for request_image_load method"""
+
+    def test_request_image_load_no_loader(self):
+        """Test request_image_load when loader not initialized"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        mock_image_data = Mock()
+
+        # Should not raise
+        obj.request_image_load(mock_image_data)
+
+    def test_request_image_load_empty_path(self):
+        """Test request_image_load with empty image path"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        obj.async_image_loader = Mock()
+
+        mock_image_data = Mock()
+        mock_image_data.image_path = ""
+
+        obj.request_image_load(mock_image_data)
+
+        obj.async_image_loader.request_load.assert_not_called()
+
+    def test_request_image_load_non_assets_path_skipped(self):
+        """Test request_image_load skips paths outside assets folder"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        obj.async_image_loader = Mock()
+
+        mock_image_data = Mock()
+        mock_image_data.image_path = "/absolute/path/image.jpg"
+
+        obj.request_image_load(mock_image_data)
+
+        obj.async_image_loader.request_load.assert_not_called()
+
+    def test_request_image_load_path_not_resolved(self):
+        """Test request_image_load when path resolution fails"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        obj.async_image_loader = Mock()
+
+        mock_image_data = Mock()
+        mock_image_data.image_path = "assets/missing.jpg"
+        mock_image_data.resolve_image_path.return_value = None
+
+        obj.request_image_load(mock_image_data)
+
+        obj.async_image_loader.request_load.assert_not_called()
+
+    def test_request_image_load_success(self, tmp_path):
+        """Test successful request_image_load"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin, LoadPriority
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        obj.async_image_loader = Mock()
+
+        # Create actual file
+        asset_path = tmp_path / "assets" / "photo.jpg"
+        asset_path.parent.mkdir(parents=True)
+        asset_path.write_text("test")
+
+        mock_image_data = Mock()
+        mock_image_data.image_path = "assets/photo.jpg"
+        mock_image_data.resolve_image_path.return_value = str(asset_path)
+
+        obj.request_image_load(mock_image_data, priority=LoadPriority.HIGH)
+
+        obj.async_image_loader.request_load.assert_called_once()
+        call_kwargs = obj.async_image_loader.request_load.call_args[1]
+        assert call_kwargs["priority"] == LoadPriority.HIGH
+        assert call_kwargs["user_data"] == mock_image_data
+
+
+class TestExportPdfAsync:
+    """Tests for export_pdf_async method"""
+
+    def test_export_pdf_async_no_generator(self):
+        """Test export_pdf_async when generator not initialized"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        mock_project = Mock()
+
+        result = obj.export_pdf_async(mock_project, "/output.pdf")
+
+        assert result is False
+
+    def test_export_pdf_async_creates_progress_dialog(self, qtbot):
+        """Test export_pdf_async creates progress dialog"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+        from PyQt6.QtWidgets import QWidget
+
+        class TestWidget(QWidget, AsyncLoadingMixin):
+            pass
+
+        widget = TestWidget()
+        qtbot.addWidget(widget)
+
+        widget.async_pdf_generator = Mock()
+        widget.async_pdf_generator.export_pdf.return_value = True
+
+        mock_project = Mock()
+        mock_project.pages = [Mock(is_cover=False, is_double_spread=False)]
+
+        widget.export_pdf_async(mock_project, "/output.pdf")
+
+        assert hasattr(widget, "_pdf_progress_dialog")
+        assert widget._pdf_progress_dialog is not None
+
+    def test_export_pdf_async_calls_generator(self, qtbot):
+        """Test export_pdf_async calls the PDF generator"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+        from PyQt6.QtWidgets import QWidget
+
+        class TestWidget(QWidget, AsyncLoadingMixin):
+            pass
+
+        widget = TestWidget()
+        qtbot.addWidget(widget)
+
+        widget.async_pdf_generator = Mock()
+        widget.async_pdf_generator.export_pdf.return_value = True
+
+        mock_project = Mock()
+        mock_project.pages = []
+
+        result = widget.export_pdf_async(mock_project, "/output.pdf", export_dpi=150)
+
+        widget.async_pdf_generator.export_pdf.assert_called_once_with(mock_project, "/output.pdf", 150)
+        assert result is True
+
+
+class TestOnPdfCancel:
+    """Tests for _on_pdf_cancel callback"""
+
+    def test_on_pdf_cancel_cancels_export(self):
+        """Test that _on_pdf_cancel cancels the export"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        obj.async_pdf_generator = Mock()
+
+        obj._on_pdf_cancel()
+
+        obj.async_pdf_generator.cancel_export.assert_called_once()
+
+    def test_on_pdf_cancel_handles_no_generator(self):
+        """Test that _on_pdf_cancel handles missing generator"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        # No async_pdf_generator
+
+        # Should not raise
+        obj._on_pdf_cancel()
+
+
+class TestGetAsyncStats:
+    """Tests for get_async_stats method"""
+
+    def test_get_async_stats_empty(self):
+        """Test get_async_stats with no components initialized"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        stats = obj.get_async_stats()
+
+        assert stats == {}
+
+    def test_get_async_stats_with_loader(self):
+        """Test get_async_stats includes loader stats"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        obj.async_image_loader = Mock()
+        obj.async_image_loader.get_stats.return_value = {"loaded": 10}
+
+        stats = obj.get_async_stats()
+
+        assert "image_loader" in stats
+        assert stats["image_loader"]["loaded"] == 10
+
+    def test_get_async_stats_with_pdf_generator(self):
+        """Test get_async_stats includes PDF generator stats"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        obj.async_pdf_generator = Mock()
+        obj.async_pdf_generator.get_stats.return_value = {"exports": 5}
+
+        stats = obj.get_async_stats()
+
+        assert "pdf_generator" in stats
+        assert stats["pdf_generator"]["exports"] == 5
+
+    def test_get_async_stats_with_all_components(self):
+        """Test get_async_stats includes all component stats"""
+        from pyPhotoAlbum.mixins.async_loading import AsyncLoadingMixin
+
+        class TestClass(AsyncLoadingMixin):
+            pass
+
+        obj = TestClass()
+        obj.async_image_loader = Mock()
+        obj.async_image_loader.get_stats.return_value = {"loaded": 10}
+        obj.async_pdf_generator = Mock()
+        obj.async_pdf_generator.get_stats.return_value = {"exports": 5}
+
+        stats = obj.get_async_stats()
+
+        assert "image_loader" in stats
+        assert "pdf_generator" in stats
diff --git a/tests/test_autosave_manager.py b/tests/test_autosave_manager.py
new file mode 100644
index 0000000..a108a61
--- /dev/null
+++ b/tests/test_autosave_manager.py
@@ -0,0 +1,511 @@
+"""
+Tests for AutosaveManager
+"""
+
+import pytest
+import json
+import tempfile
+import shutil
+from pathlib import Path
+from datetime import datetime, timedelta
+from unittest.mock import Mock, patch, MagicMock
+
+from pyPhotoAlbum.autosave_manager import AutosaveManager
+
+
+class TestAutosaveManagerInit:
+    """Tests for AutosaveManager initialization"""
+
+    def test_init_creates_checkpoint_directory(self, tmp_path, monkeypatch):
+        """Test that init creates the checkpoint directory"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+
+        assert checkpoint_dir.exists()
+
+    def test_init_with_existing_directory(self, tmp_path, monkeypatch):
+        """Test init when checkpoint directory already exists"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+
+        assert checkpoint_dir.exists()
+
+
+class TestGetCheckpointPath:
+    """Tests for _get_checkpoint_path method"""
+
+    def test_get_checkpoint_path_basic(self, tmp_path, monkeypatch):
+        """Test basic checkpoint path generation"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+        path = manager._get_checkpoint_path("MyProject")
+
+        assert path.parent == checkpoint_dir
+        assert path.suffix == ".ppz"
+        assert "checkpoint_MyProject_" in path.name
+
+    def test_get_checkpoint_path_with_timestamp(self, tmp_path, monkeypatch):
+        """Test checkpoint path with specific timestamp"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+        timestamp = datetime(2024, 1, 15, 10, 30, 45)
+        path = manager._get_checkpoint_path("TestProject", timestamp)
+
+        assert "20240115_103045" in path.name
+
+    def test_get_checkpoint_path_sanitizes_name(self, tmp_path, monkeypatch):
+        """Test that special characters in project name are sanitized"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+        path = manager._get_checkpoint_path("My Project!@#$%")
+
+        # Should not contain special characters except - and _
+        name_without_ext = path.stem
+        for char in name_without_ext:
+            assert char.isalnum() or char in "-_", f"Invalid char: {char}"
+
+
+class TestCreateCheckpoint:
+    """Tests for create_checkpoint method"""
+
+    def test_create_checkpoint_success(self, tmp_path, monkeypatch):
+        """Test successful checkpoint creation"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+
+        # Mock save_to_zip - note the return value format
+        with patch("pyPhotoAlbum.autosave_manager.save_to_zip") as mock_save:
+            mock_save.return_value = (True, "Success")
+
+            mock_project = Mock()
+            mock_project.name = "TestProject"
+            mock_project.file_path = "/path/to/project.ppz"
+
+            success, message = manager.create_checkpoint(mock_project)
+
+            assert success is True
+            assert "Checkpoint created" in message
+            mock_save.assert_called_once()
+
+    def test_create_checkpoint_failure(self, tmp_path, monkeypatch):
+        """Test checkpoint creation failure"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+
+        with patch("pyPhotoAlbum.autosave_manager.save_to_zip") as mock_save:
+            mock_save.return_value = (False, "Disk full")
+
+            mock_project = Mock()
+            mock_project.name = "TestProject"
+
+            success, message = manager.create_checkpoint(mock_project)
+
+            assert success is False
+            assert "Checkpoint failed" in message
+
+    def test_create_checkpoint_exception(self, tmp_path, monkeypatch):
+        """Test checkpoint creation with exception"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+
+        with patch("pyPhotoAlbum.autosave_manager.save_to_zip") as mock_save:
+            mock_save.side_effect = Exception("IO Error")
+
+            mock_project = Mock()
+            mock_project.name = "TestProject"
+
+            success, message = manager.create_checkpoint(mock_project)
+
+            assert success is False
+            assert "Checkpoint error" in message
+
+
+class TestSaveCheckpointMetadata:
+    """Tests for _save_checkpoint_metadata method"""
+
+    def test_save_metadata(self, tmp_path, monkeypatch):
+        """Test saving checkpoint metadata"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+
+        mock_project = Mock()
+        mock_project.name = "TestProject"
+        mock_project.file_path = "/path/to/original.ppz"
+
+        checkpoint_path = checkpoint_dir / "checkpoint_TestProject_20240115_103045.ppz"
+        checkpoint_path.touch()
+
+        manager._save_checkpoint_metadata(mock_project, checkpoint_path)
+
+        metadata_path = checkpoint_path.with_suffix(".json")
+        assert metadata_path.exists()
+
+        with open(metadata_path, "r") as f:
+            metadata = json.load(f)
+
+        assert metadata["project_name"] == "TestProject"
+        assert metadata["original_path"] == "/path/to/original.ppz"
+        assert "timestamp" in metadata
+
+
+class TestListCheckpoints:
+    """Tests for list_checkpoints method"""
+
+    def test_list_checkpoints_empty(self, tmp_path, monkeypatch):
+        """Test listing checkpoints when none exist"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+        checkpoints = manager.list_checkpoints()
+
+        assert checkpoints == []
+
+    def test_list_checkpoints_with_files(self, tmp_path, monkeypatch):
+        """Test listing checkpoints with existing files"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        # Create some checkpoint files
+        cp1 = checkpoint_dir / "checkpoint_Project1_20240115_100000.ppz"
+        cp2 = checkpoint_dir / "checkpoint_Project2_20240115_110000.ppz"
+        cp1.touch()
+        cp2.touch()
+
+        # Create metadata for first checkpoint
+        metadata1 = {"project_name": "Project1", "timestamp": "2024-01-15T10:00:00"}
+        with open(cp1.with_suffix(".json"), "w") as f:
+            json.dump(metadata1, f)
+
+        manager = AutosaveManager()
+        checkpoints = manager.list_checkpoints()
+
+        assert len(checkpoints) == 2
+
+    def test_list_checkpoints_filter_by_project(self, tmp_path, monkeypatch):
+        """Test listing checkpoints filtered by project name"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        # Create checkpoint files with metadata
+        cp1 = checkpoint_dir / "checkpoint_Project1_20240115_100000.ppz"
+        cp2 = checkpoint_dir / "checkpoint_Project2_20240115_110000.ppz"
+        cp1.touch()
+        cp2.touch()
+
+        metadata1 = {"project_name": "Project1", "timestamp": "2024-01-15T10:00:00"}
+        metadata2 = {"project_name": "Project2", "timestamp": "2024-01-15T11:00:00"}
+
+        with open(cp1.with_suffix(".json"), "w") as f:
+            json.dump(metadata1, f)
+        with open(cp2.with_suffix(".json"), "w") as f:
+            json.dump(metadata2, f)
+
+        manager = AutosaveManager()
+        checkpoints = manager.list_checkpoints("Project1")
+
+        assert len(checkpoints) == 1
+        assert checkpoints[0][1]["project_name"] == "Project1"
+
+    def test_list_checkpoints_sorted_by_timestamp(self, tmp_path, monkeypatch):
+        """Test that checkpoints are sorted by timestamp (newest first)"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        # Create checkpoints with different timestamps
+        cp1 = checkpoint_dir / "checkpoint_Project_20240115_080000.ppz"
+        cp2 = checkpoint_dir / "checkpoint_Project_20240115_120000.ppz"
+        cp3 = checkpoint_dir / "checkpoint_Project_20240115_100000.ppz"
+        cp1.touch()
+        cp2.touch()
+        cp3.touch()
+
+        for cp, hour in [(cp1, "08"), (cp2, "12"), (cp3, "10")]:
+            metadata = {"project_name": "Project", "timestamp": f"2024-01-15T{hour}:00:00"}
+            with open(cp.with_suffix(".json"), "w") as f:
+                json.dump(metadata, f)
+
+        manager = AutosaveManager()
+        checkpoints = manager.list_checkpoints()
+
+        # Should be sorted newest first: 12:00, 10:00, 08:00
+        assert "12:00:00" in checkpoints[0][1]["timestamp"]
+        assert "10:00:00" in checkpoints[1][1]["timestamp"]
+        assert "08:00:00" in checkpoints[2][1]["timestamp"]
+
+
+class TestLoadCheckpoint:
+    """Tests for load_checkpoint method"""
+
+    def test_load_checkpoint_success(self, tmp_path, monkeypatch):
+        """Test successful checkpoint loading"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+
+        with patch("pyPhotoAlbum.autosave_manager.load_from_zip") as mock_load:
+            mock_project = Mock()
+            mock_load.return_value = mock_project
+
+            checkpoint_path = checkpoint_dir / "checkpoint_Test.ppz"
+            success, result = manager.load_checkpoint(checkpoint_path)
+
+            assert success is True
+            assert result == mock_project
+
+    def test_load_checkpoint_failure(self, tmp_path, monkeypatch):
+        """Test checkpoint loading failure"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+
+        with patch("pyPhotoAlbum.autosave_manager.load_from_zip") as mock_load:
+            mock_load.side_effect = Exception("Corrupt file")
+
+            checkpoint_path = checkpoint_dir / "checkpoint_Test.ppz"
+            success, result = manager.load_checkpoint(checkpoint_path)
+
+            assert success is False
+            assert "Failed to load checkpoint" in result
+
+
+class TestDeleteCheckpoint:
+    """Tests for delete_checkpoint method"""
+
+    def test_delete_checkpoint_success(self, tmp_path, monkeypatch):
+        """Test successful checkpoint deletion"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        # Create checkpoint and metadata files
+        cp = checkpoint_dir / "checkpoint_Test.ppz"
+        cp.touch()
+        metadata = cp.with_suffix(".json")
+        metadata.touch()
+
+        manager = AutosaveManager()
+        result = manager.delete_checkpoint(cp)
+
+        assert result is True
+        assert not cp.exists()
+        assert not metadata.exists()
+
+    def test_delete_checkpoint_nonexistent(self, tmp_path, monkeypatch):
+        """Test deleting nonexistent checkpoint"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+        cp = checkpoint_dir / "nonexistent.ppz"
+        result = manager.delete_checkpoint(cp)
+
+        assert result is True  # Should succeed even if file doesn't exist
+
+
+class TestDeleteAllCheckpoints:
+    """Tests for delete_all_checkpoints method"""
+
+    def test_delete_all_checkpoints(self, tmp_path, monkeypatch):
+        """Test deleting all checkpoints"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        # Create multiple checkpoints
+        for i in range(3):
+            cp = checkpoint_dir / f"checkpoint_Project_{i}.ppz"
+            cp.touch()
+            metadata = {"project_name": "Project", "timestamp": f"2024-01-15T{i}:00:00"}
+            with open(cp.with_suffix(".json"), "w") as f:
+                json.dump(metadata, f)
+
+        manager = AutosaveManager()
+        manager.delete_all_checkpoints()
+
+        remaining = list(checkpoint_dir.glob("checkpoint_*.ppz"))
+        assert len(remaining) == 0
+
+    def test_delete_all_checkpoints_filtered(self, tmp_path, monkeypatch):
+        """Test deleting all checkpoints for specific project"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        # Create checkpoints for different projects
+        for name in ["ProjectA", "ProjectB", "ProjectA"]:
+            cp = checkpoint_dir / f"checkpoint_{name}_{datetime.now().strftime('%Y%m%d_%H%M%S%f')}.ppz"
+            cp.touch()
+            metadata = {"project_name": name, "timestamp": datetime.now().isoformat()}
+            with open(cp.with_suffix(".json"), "w") as f:
+                json.dump(metadata, f)
+
+        manager = AutosaveManager()
+        manager.delete_all_checkpoints("ProjectA")
+
+        # Only ProjectB should remain
+        remaining = list(checkpoint_dir.glob("checkpoint_*.ppz"))
+        assert len(remaining) == 1
+        assert "ProjectB" in remaining[0].name
+
+
+class TestCleanupOldCheckpoints:
+    """Tests for cleanup_old_checkpoints method"""
+
+    def test_cleanup_old_checkpoints_by_age(self, tmp_path, monkeypatch):
+        """Test cleanup of old checkpoints by age"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        # Create old and new checkpoints
+        old_time = datetime.now() - timedelta(hours=48)
+        new_time = datetime.now() - timedelta(hours=1)
+
+        old_cp = checkpoint_dir / "checkpoint_Project_old.ppz"
+        new_cp = checkpoint_dir / "checkpoint_Project_new.ppz"
+        old_cp.touch()
+        new_cp.touch()
+
+        old_metadata = {"project_name": "Project", "timestamp": old_time.isoformat()}
+        new_metadata = {"project_name": "Project", "timestamp": new_time.isoformat()}
+
+        with open(old_cp.with_suffix(".json"), "w") as f:
+            json.dump(old_metadata, f)
+        with open(new_cp.with_suffix(".json"), "w") as f:
+            json.dump(new_metadata, f)
+
+        manager = AutosaveManager()
+        manager.cleanup_old_checkpoints(max_age_hours=24)
+
+        # Only new checkpoint should remain
+        remaining = list(checkpoint_dir.glob("checkpoint_*.ppz"))
+        assert len(remaining) == 1
+        assert "new" in remaining[0].name
+
+    def test_cleanup_old_checkpoints_by_count(self, tmp_path, monkeypatch):
+        """Test cleanup of checkpoints by count"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        # Create many recent checkpoints
+        for i in range(5):
+            timestamp = datetime.now() - timedelta(hours=i)
+            cp = checkpoint_dir / f"checkpoint_Project_{i:02d}.ppz"
+            cp.touch()
+            metadata = {"project_name": "Project", "timestamp": timestamp.isoformat()}
+            with open(cp.with_suffix(".json"), "w") as f:
+                json.dump(metadata, f)
+
+        manager = AutosaveManager()
+        manager.cleanup_old_checkpoints(max_age_hours=24 * 7, max_count=3)
+
+        # Should only keep 3 most recent
+        remaining = list(checkpoint_dir.glob("checkpoint_*.ppz"))
+        assert len(remaining) == 3
+
+
+class TestHasCheckpoints:
+    """Tests for has_checkpoints method"""
+
+    def test_has_checkpoints_true(self, tmp_path, monkeypatch):
+        """Test has_checkpoints returns True when checkpoints exist"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        cp = checkpoint_dir / "checkpoint_Test.ppz"
+        cp.touch()
+
+        manager = AutosaveManager()
+        assert manager.has_checkpoints() is True
+
+    def test_has_checkpoints_false(self, tmp_path, monkeypatch):
+        """Test has_checkpoints returns False when no checkpoints"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+        assert manager.has_checkpoints() is False
+
+
+class TestGetLatestCheckpoint:
+    """Tests for get_latest_checkpoint method"""
+
+    def test_get_latest_checkpoint(self, tmp_path, monkeypatch):
+        """Test getting the latest checkpoint"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        # Create checkpoints with different timestamps
+        for hour in [8, 10, 12]:
+            cp = checkpoint_dir / f"checkpoint_Project_{hour:02d}.ppz"
+            cp.touch()
+            metadata = {"project_name": "Project", "timestamp": f"2024-01-15T{hour:02d}:00:00"}
+            with open(cp.with_suffix(".json"), "w") as f:
+                json.dump(metadata, f)
+
+        manager = AutosaveManager()
+        result = manager.get_latest_checkpoint()
+
+        assert result is not None
+        assert "12:00:00" in result[1]["timestamp"]
+
+    def test_get_latest_checkpoint_none(self, tmp_path, monkeypatch):
+        """Test getting latest checkpoint when none exist"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        manager = AutosaveManager()
+        result = manager.get_latest_checkpoint()
+
+        assert result is None
+
+    def test_get_latest_checkpoint_filtered(self, tmp_path, monkeypatch):
+        """Test getting latest checkpoint for specific project"""
+        checkpoint_dir = tmp_path / "checkpoints"
+        checkpoint_dir.mkdir(parents=True)
+        monkeypatch.setattr(AutosaveManager, "CHECKPOINT_DIR", checkpoint_dir)
+
+        # Create checkpoints for different projects
+        for name, hour in [("ProjectA", 10), ("ProjectB", 12), ("ProjectA", 8)]:
+            cp = checkpoint_dir / f"checkpoint_{name}_{hour:02d}.ppz"
+            cp.touch()
+            metadata = {"project_name": name, "timestamp": f"2024-01-15T{hour:02d}:00:00"}
+            with open(cp.with_suffix(".json"), "w") as f:
+                json.dump(metadata, f)
+
+        manager = AutosaveManager()
+        result = manager.get_latest_checkpoint("ProjectA")
+
+        assert result is not None
+        assert result[1]["project_name"] == "ProjectA"
+        assert "10:00:00" in result[1]["timestamp"]  # Latest for ProjectA
diff --git a/tests/test_base_mixin.py b/tests/test_base_mixin.py
index aea24dd..9db9655 100755
--- a/tests/test_base_mixin.py
+++ b/tests/test_base_mixin.py
@@ -249,7 +249,7 @@ class TestDialogMethods:
         qtbot.addWidget(window)
 
         mock_critical = Mock()
-        monkeypatch.setattr(QMessageBox, 'critical', mock_critical)
+        monkeypatch.setattr(QMessageBox, "critical", mock_critical)
 
         window.show_error("Error Title", "Error message")
 
@@ -260,7 +260,7 @@ class TestDialogMethods:
         qtbot.addWidget(window)
 
         mock_warning = Mock()
-        monkeypatch.setattr(QMessageBox, 'warning', mock_warning)
+        monkeypatch.setattr(QMessageBox, "warning", mock_warning)
 
         window.show_warning("Warning Title", "Warning message")
 
@@ -271,7 +271,7 @@ class TestDialogMethods:
         qtbot.addWidget(window)
 
         mock_info = Mock()
-        monkeypatch.setattr(QMessageBox, 'information', mock_info)
+        monkeypatch.setattr(QMessageBox, "information", mock_info)
 
         window.show_info("Info Title", "Info message")
 
@@ -309,7 +309,7 @@ class TestRequirePage:
         window._gl_widget = Mock()
 
         mock_warning = Mock()
-        monkeypatch.setattr(QMessageBox, 'warning', mock_warning)
+        monkeypatch.setattr(QMessageBox, "warning", mock_warning)
 
         result = window.require_page(show_warning=True)
 
@@ -366,7 +366,7 @@ class TestRequireSelection:
         window._gl_widget = gl_widget
 
         mock_info = Mock()
-        monkeypatch.setattr(QMessageBox, 'information', mock_info)
+        monkeypatch.setattr(QMessageBox, "information", mock_info)
 
         result = window.require_selection(min_count=1, show_warning=True)
 
@@ -386,7 +386,7 @@ class TestRequireSelection:
         window._gl_widget = gl_widget
 
         mock_info = Mock()
-        monkeypatch.setattr(QMessageBox, 'information', mock_info)
+        monkeypatch.setattr(QMessageBox, "information", mock_info)
 
         result = window.require_selection(min_count=3, show_warning=True)
 
diff --git a/tests/test_commands.py b/tests/test_commands.py
index 9fbd140..70ec2eb 100755
--- a/tests/test_commands.py
+++ b/tests/test_commands.py
@@ -16,7 +16,7 @@ from pyPhotoAlbum.commands import (
     ChangeZOrderCommand,
     StateChangeCommand,
     CommandHistory,
-    _normalize_asset_path
+    _normalize_asset_path,
 )
 from pyPhotoAlbum.models import ImageData, TextBoxData, PlaceholderData
 from pyPhotoAlbum.page_layout import PageLayout
@@ -107,9 +107,9 @@ class TestAddElementCommand:
 
         data = cmd.serialize()
 
-        assert data['type'] == 'add_element'
-        assert 'element' in data
-        assert data['executed'] is True
+        assert data["type"] == "add_element"
+        assert "element" in data
+        assert data["executed"] is True
 
     def test_add_element_with_asset_manager(self):
         """Test add element with asset manager reference"""
@@ -164,8 +164,8 @@ class TestDeleteElementCommand:
         cmd = DeleteElementCommand(layout, element)
         data = cmd.serialize()
 
-        assert data['type'] == 'delete_element'
-        assert 'element' in data
+        assert data["type"] == "delete_element"
+        assert "element" in data
 
 
 class TestMoveElementCommand:
@@ -198,9 +198,9 @@ class TestMoveElementCommand:
         cmd = MoveElementCommand(element, old_position=(100, 100), new_position=(200, 200))
         data = cmd.serialize()
 
-        assert data['type'] == 'move_element'
-        assert data['old_position'] == (100, 100)
-        assert data['new_position'] == (200, 200)
+        assert data["type"] == "move_element"
+        assert data["old_position"] == (100, 100)
+        assert data["new_position"] == (200, 200)
 
 
 class TestResizeElementCommand:
@@ -211,11 +211,7 @@ class TestResizeElementCommand:
         element = ImageData(image_path="/test.jpg", x=100, y=100, width=200, height=150)
 
         cmd = ResizeElementCommand(
-            element,
-            old_position=(100, 100),
-            old_size=(200, 150),
-            new_position=(100, 100),
-            new_size=(300, 225)
+            element, old_position=(100, 100), old_size=(200, 150), new_position=(100, 100), new_size=(300, 225)
         )
         cmd.execute()
 
@@ -226,11 +222,7 @@ class TestResizeElementCommand:
         element = ImageData(image_path="/test.jpg", x=100, y=100, width=200, height=150)
 
         cmd = ResizeElementCommand(
-            element,
-            old_position=(100, 100),
-            old_size=(200, 150),
-            new_position=(100, 100),
-            new_size=(300, 225)
+            element, old_position=(100, 100), old_size=(200, 150), new_position=(100, 100), new_size=(300, 225)
         )
         cmd.execute()
 
@@ -243,11 +235,7 @@ class TestResizeElementCommand:
         element = ImageData(image_path="/test.jpg", x=100, y=100, width=200, height=150)
 
         cmd = ResizeElementCommand(
-            element,
-            old_position=(100, 100),
-            old_size=(200, 150),
-            new_position=(90, 90),
-            new_size=(220, 165)
+            element, old_position=(100, 100), old_size=(200, 150), new_position=(90, 90), new_size=(220, 165)
         )
         cmd.execute()
 
@@ -298,9 +286,9 @@ class TestRotateElementCommand:
         cmd = RotateElementCommand(element, old_rotation=0, new_rotation=45)
         data = cmd.serialize()
 
-        assert data['type'] == 'rotate_element'
-        assert data['old_rotation'] == 0
-        assert data['new_rotation'] == 45
+        assert data["type"] == "rotate_element"
+        assert data["old_rotation"] == 0
+        assert data["new_rotation"] == 45
 
 
 class TestAdjustImageCropCommand:
@@ -310,32 +298,25 @@ class TestAdjustImageCropCommand:
         """Test adjusting image crop"""
         element = ImageData(
             image_path="/test.jpg",
-            x=100, y=100,
-            width=200, height=150,
-            crop_info={'x': 0.0, 'y': 0.0, 'width': 1.0, 'height': 1.0}
+            x=100,
+            y=100,
+            width=200,
+            height=150,
+            crop_info={"x": 0.0, "y": 0.0, "width": 1.0, "height": 1.0},
         )
 
-        new_crop = {'x': 0.1, 'y': 0.1, 'width': 0.8, 'height': 0.8}
-        cmd = AdjustImageCropCommand(
-            element,
-            old_crop_info=element.crop_info.copy(),
-            new_crop_info=new_crop
-        )
+        new_crop = {"x": 0.1, "y": 0.1, "width": 0.8, "height": 0.8}
+        cmd = AdjustImageCropCommand(element, old_crop_info=element.crop_info.copy(), new_crop_info=new_crop)
         cmd.execute()
 
         assert element.crop_info == new_crop
 
     def test_adjust_crop_undo(self):
         """Test undoing crop adjustment"""
-        old_crop = {'x': 0.0, 'y': 0.0, 'width': 1.0, 'height': 1.0}
-        element = ImageData(
-            image_path="/test.jpg",
-            x=100, y=100,
-            width=200, height=150,
-            crop_info=old_crop.copy()
-        )
+        old_crop = {"x": 0.0, "y": 0.0, "width": 1.0, "height": 1.0}
+        element = ImageData(image_path="/test.jpg", x=100, y=100, width=200, height=150, crop_info=old_crop.copy())
 
-        new_crop = {'x': 0.1, 'y': 0.1, 'width': 0.8, 'height': 0.8}
+        new_crop = {"x": 0.1, "y": 0.1, "width": 0.8, "height": 0.8}
         cmd = AdjustImageCropCommand(element, old_crop_info=old_crop, new_crop_info=new_crop)
         cmd.execute()
 
@@ -399,10 +380,7 @@ class TestResizeElementsCommand:
         element2.size = (300, 300)
 
         # Command expects list of (element, old_position, old_size) tuples
-        changes = [
-            (element1, (100, 100), (100, 100)),
-            (element2, (200, 200), (150, 150))
-        ]
+        changes = [(element1, (100, 100), (100, 100)), (element2, (200, 200), (150, 150))]
 
         cmd = ResizeElementsCommand(changes)
         cmd.execute()
@@ -421,10 +399,7 @@ class TestResizeElementsCommand:
         element2.size = (300, 300)
 
         # Command expects list of (element, old_position, old_size) tuples
-        changes = [
-            (element1, (100, 100), (100, 100)),
-            (element2, (200, 200), (150, 150))
-        ]
+        changes = [(element1, (100, 100), (100, 100)), (element2, (200, 200), (150, 150))]
 
         cmd = ResizeElementsCommand(changes)
         cmd.execute()
@@ -476,81 +451,68 @@ class TestStateChangeCommand:
 
     def test_state_change_undo(self):
         """Test undoing state change"""
-        element = TextBoxData(
-            text_content="Old Text",
-            x=100, y=100,
-            width=200, height=100
-        )
+        element = TextBoxData(text_content="Old Text", x=100, y=100, width=200, height=100)
 
         # Define restore function
         def restore_state(state):
-            element.text_content = state['text_content']
+            element.text_content = state["text_content"]
 
-        old_state = {'text_content': 'Old Text'}
-        new_state = {'text_content': 'New Text'}
+        old_state = {"text_content": "Old Text"}
+        new_state = {"text_content": "New Text"}
 
         # Apply new state first
-        element.text_content = 'New Text'
+        element.text_content = "New Text"
 
         cmd = StateChangeCommand(
-            description="Change text",
-            restore_func=restore_state,
-            before_state=old_state,
-            after_state=new_state
+            description="Change text", restore_func=restore_state, before_state=old_state, after_state=new_state
         )
 
         # Undo should restore old state
         cmd.undo()
-        assert element.text_content == 'Old Text'
+        assert element.text_content == "Old Text"
 
     def test_state_change_redo(self):
         """Test redoing state change"""
-        element = TextBoxData(
-            text_content="Old Text",
-            x=100, y=100,
-            width=200, height=100
-        )
+        element = TextBoxData(text_content="Old Text", x=100, y=100, width=200, height=100)
 
         # Define restore function
         def restore_state(state):
-            element.text_content = state['text_content']
+            element.text_content = state["text_content"]
 
-        old_state = {'text_content': 'Old Text'}
-        new_state = {'text_content': 'New Text'}
+        old_state = {"text_content": "Old Text"}
+        new_state = {"text_content": "New Text"}
 
         # Apply new state first
-        element.text_content = 'New Text'
+        element.text_content = "New Text"
 
         cmd = StateChangeCommand(
-            description="Change text",
-            restore_func=restore_state,
-            before_state=old_state,
-            after_state=new_state
+            description="Change text", restore_func=restore_state, before_state=old_state, after_state=new_state
         )
 
         # Undo then redo
         cmd.undo()
-        assert element.text_content == 'Old Text'
+        assert element.text_content == "Old Text"
 
         cmd.redo()
-        assert element.text_content == 'New Text'
+        assert element.text_content == "New Text"
 
     def test_state_change_serialization(self):
         """Test serializing state change command"""
+
         def restore_func(state):
             pass
 
         cmd = StateChangeCommand(
             description="Test operation",
             restore_func=restore_func,
-            before_state={'test': 'before'},
-            after_state={'test': 'after'}
+            before_state={"test": "before"},
+            after_state={"test": "after"},
         )
 
         data = cmd.serialize()
 
-        assert data['type'] == 'state_change'
-        assert data['description'] == 'Test operation'
+        assert data["type"] == "state_change"
+        assert data["description"] == "Test operation"
 
 
 class TestCommandHistory:
@@ -656,7 +618,7 @@ class TestCommandHistory:
         layout = PageLayout(width=210, height=297)
 
         for i in range(5):
-            element = ImageData(image_path=f"/test{i}.jpg", x=i*10, y=i*10, width=100, height=100)
+            element = ImageData(image_path=f"/test{i}.jpg", x=i * 10, y=i * 10, width=100, height=100)
             history.execute(AddElementCommand(layout, element))
 
         # Should only have 3 commands in history (max_history)
@@ -678,8 +640,8 @@ class TestCommandHistory:
 
         # Serialize
         data = history.serialize()
-        assert len(data['undo_stack']) == 1
-        assert data['undo_stack'][0]['type'] == 'add_element'
+        assert len(data["undo_stack"]) == 1
+        assert data["undo_stack"][0]["type"] == "add_element"
 
         # Create mock project for deserialization
         mock_project = Mock()
@@ -734,7 +696,7 @@ class TestCommandHistory:
 
         # Manually build serialized history data
         data = {
-            'undo_stack': [
+            "undo_stack": [
                 cmd1.serialize(),
                 cmd2.serialize(),
                 cmd3.serialize(),
@@ -745,8 +707,8 @@ class TestCommandHistory:
                 cmd8.serialize(),
                 cmd9.serialize(),
             ],
-            'redo_stack': [],
-            'max_history': 100
+            "redo_stack": [],
+            "max_history": 100,
         }
 
         # Create mock project
@@ -758,15 +720,15 @@ class TestCommandHistory:
         new_history.deserialize(data, mock_project)
 
         assert len(new_history.undo_stack) == 9
-        assert new_history.undo_stack[0].__class__.__name__ == 'AddElementCommand'
-        assert new_history.undo_stack[1].__class__.__name__ == 'DeleteElementCommand'
-        assert new_history.undo_stack[2].__class__.__name__ == 'MoveElementCommand'
-        assert new_history.undo_stack[3].__class__.__name__ == 'ResizeElementCommand'
-        assert new_history.undo_stack[4].__class__.__name__ == 'RotateElementCommand'
-        assert new_history.undo_stack[5].__class__.__name__ == 'AdjustImageCropCommand'
-        assert new_history.undo_stack[6].__class__.__name__ == 'AlignElementsCommand'
-        assert new_history.undo_stack[7].__class__.__name__ == 'ResizeElementsCommand'
-        assert new_history.undo_stack[8].__class__.__name__ == 'ChangeZOrderCommand'
+        assert new_history.undo_stack[0].__class__.__name__ == "AddElementCommand"
+        assert new_history.undo_stack[1].__class__.__name__ == "DeleteElementCommand"
+        assert new_history.undo_stack[2].__class__.__name__ == "MoveElementCommand"
+        assert new_history.undo_stack[3].__class__.__name__ == "ResizeElementCommand"
+        assert new_history.undo_stack[4].__class__.__name__ == "RotateElementCommand"
+        assert new_history.undo_stack[5].__class__.__name__ == "AdjustImageCropCommand"
+        assert new_history.undo_stack[6].__class__.__name__ == "AlignElementsCommand"
+        assert new_history.undo_stack[7].__class__.__name__ == "ResizeElementsCommand"
+        assert new_history.undo_stack[8].__class__.__name__ == "ChangeZOrderCommand"
 
     def test_history_deserialize_unknown_command_type(self):
         """Test deserializing unknown command type returns None and continues"""
@@ -774,12 +736,12 @@ class TestCommandHistory:
         mock_project = Mock()
 
         data = {
-            'undo_stack': [
-                {'type': 'unknown_command', 'data': 'test'},
-                {'type': 'add_element', 'element': ImageData().serialize(), 'executed': True}
+            "undo_stack": [
+                {"type": "unknown_command", "data": "test"},
+                {"type": "add_element", "element": ImageData().serialize(), "executed": True},
             ],
-            'redo_stack': [],
-            'max_history': 100
+            "redo_stack": [],
+            "max_history": 100,
         }
 
         # Should not raise exception, just skip unknown command
@@ -787,7 +749,7 @@ class TestCommandHistory:
 
         # Should only have the valid command
         assert len(history.undo_stack) == 1
-        assert history.undo_stack[0].__class__.__name__ == 'AddElementCommand'
+        assert history.undo_stack[0].__class__.__name__ == "AddElementCommand"
 
     def test_history_deserialize_malformed_command(self):
         """Test deserializing malformed command handles exception gracefully"""
@@ -795,13 +757,17 @@ class TestCommandHistory:
         mock_project = Mock()
 
         data = {
-            'undo_stack': [
-                {'type': 'add_element'},  # Missing required 'element' field
-                {'type': 'move_element', 'element': ImageData().serialize(),
-                 'old_position': (0, 0), 'new_position': (10, 10)}
+            "undo_stack": [
+                {"type": "add_element"},  # Missing required 'element' field
+                {
+                    "type": "move_element",
+                    "element": ImageData().serialize(),
+                    "old_position": (0, 0),
+                    "new_position": (10, 10),
+                },
             ],
-            'redo_stack': [],
-            'max_history': 100
+            "redo_stack": [],
+            "max_history": 100,
         }
 
         # Should not raise exception, just skip malformed command
@@ -809,7 +775,7 @@ class TestCommandHistory:
 
         # Should only have the valid command
         assert len(history.undo_stack) == 1
-        assert history.undo_stack[0].__class__.__name__ == 'MoveElementCommand'
+        assert history.undo_stack[0].__class__.__name__ == "MoveElementCommand"
 
     def test_history_serialize_deserialize_with_redo_stack(self):
         """Test serializing and deserializing with items in redo stack"""
@@ -826,8 +792,8 @@ class TestCommandHistory:
 
         # Serialize
         data = history.serialize()
-        assert len(data['undo_stack']) == 1
-        assert len(data['redo_stack']) == 1
+        assert len(data["undo_stack"]) == 1
+        assert len(data["redo_stack"]) == 1
 
         # Deserialize
         mock_project = Mock()
diff --git a/tests/test_distribution_ops_mixin.py b/tests/test_distribution_ops_mixin.py
index 83d2498..7b5dd8e 100755
--- a/tests/test_distribution_ops_mixin.py
+++ b/tests/test_distribution_ops_mixin.py
@@ -56,7 +56,7 @@ class TestGetSelectedElementsList:
 class TestDistributeHorizontally:
     """Test distribute_horizontally method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.distribution_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.distribution_ops.AlignmentManager")
     def test_distribute_horizontally_success(self, mock_manager, qtbot):
         window = TestDistributionWindow()
         qtbot.addWidget(window)
@@ -70,7 +70,7 @@ class TestDistributeHorizontally:
         mock_manager.distribute_horizontally.return_value = [
             (element1, (0, 0)),
             (element2, (150, 0)),
-            (element3, (500, 0))
+            (element3, (500, 0)),
         ]
 
         window.distribute_horizontally()
@@ -98,7 +98,7 @@ class TestDistributeHorizontally:
 class TestDistributeVertically:
     """Test distribute_vertically method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.distribution_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.distribution_ops.AlignmentManager")
     def test_distribute_vertically_success(self, mock_manager, qtbot):
         window = TestDistributionWindow()
         qtbot.addWidget(window)
@@ -112,7 +112,7 @@ class TestDistributeVertically:
         mock_manager.distribute_vertically.return_value = [
             (element1, (0, 0)),
             (element2, (0, 150)),
-            (element3, (0, 500))
+            (element3, (0, 500)),
         ]
 
         window.distribute_vertically()
@@ -125,7 +125,7 @@ class TestDistributeVertically:
 class TestSpaceHorizontally:
     """Test space_horizontally method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.distribution_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.distribution_ops.AlignmentManager")
     def test_space_horizontally_success(self, mock_manager, qtbot):
         window = TestDistributionWindow()
         qtbot.addWidget(window)
@@ -136,11 +136,7 @@ class TestSpaceHorizontally:
 
         window.gl_widget.selected_elements = {element1, element2, element3}
 
-        mock_manager.space_horizontally.return_value = [
-            (element1, (0, 0)),
-            (element2, (100, 0)),
-            (element3, (200, 0))
-        ]
+        mock_manager.space_horizontally.return_value = [(element1, (0, 0)), (element2, (100, 0)), (element3, (200, 0))]
 
         window.space_horizontally()
 
@@ -152,7 +148,7 @@ class TestSpaceHorizontally:
 class TestSpaceVertically:
     """Test space_vertically method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.distribution_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.distribution_ops.AlignmentManager")
     def test_space_vertically_success(self, mock_manager, qtbot):
         window = TestDistributionWindow()
         qtbot.addWidget(window)
@@ -163,11 +159,7 @@ class TestSpaceVertically:
 
         window.gl_widget.selected_elements = {element1, element2, element3}
 
-        mock_manager.space_vertically.return_value = [
-            (element1, (0, 0)),
-            (element2, (0, 100)),
-            (element3, (0, 200))
-        ]
+        mock_manager.space_vertically.return_value = [(element1, (0, 0)), (element2, (0, 100)), (element3, (0, 200))]
 
         window.space_vertically()
 
@@ -178,7 +170,7 @@ class TestSpaceVertically:
 class TestDistributionCommandPattern:
     """Test distribution operations with command pattern"""
 
-    @patch('pyPhotoAlbum.mixins.operations.distribution_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.distribution_ops.AlignmentManager")
     def test_distribution_creates_command(self, mock_manager, qtbot):
         window = TestDistributionWindow()
         qtbot.addWidget(window)
@@ -192,7 +184,7 @@ class TestDistributionCommandPattern:
         mock_manager.distribute_horizontally.return_value = [
             (element1, (0, 0)),
             (element2, (100, 0)),
-            (element3, (200, 0))
+            (element3, (200, 0)),
         ]
 
         assert not window.project.history.can_undo()
diff --git a/tests/test_edit_ops_mixin.py b/tests/test_edit_ops_mixin.py
index cd5afcd..d0df1b4 100755
--- a/tests/test_edit_ops_mixin.py
+++ b/tests/test_edit_ops_mixin.py
@@ -31,7 +31,7 @@ class TestEditWindow(EditOperationsMixin, QMainWindow):
         return len(self.gl_widget.selected_elements) >= min_count
 
     def get_current_page(self):
-        if hasattr(self, '_current_page'):
+        if hasattr(self, "_current_page"):
             return self._current_page
         return None
 
diff --git a/tests/test_element_manipulation_mixin.py b/tests/test_element_manipulation_mixin.py
index af9989c..859a0fd 100755
--- a/tests/test_element_manipulation_mixin.py
+++ b/tests/test_element_manipulation_mixin.py
@@ -15,6 +15,7 @@ from pyPhotoAlbum.page_layout import PageLayout
 # Create test widget combining necessary mixins
 class TestManipulationWidget(ElementManipulationMixin, ElementSelectionMixin, QOpenGLWidget):
     """Test widget combining manipulation and selection mixins"""
+
     def __init__(self):
         super().__init__()
         self._page_renderers = []
@@ -36,11 +37,7 @@ class TestElementManipulationInitialization:
         assert widget.rotation_mode is False
         assert widget.rotation_start_angle is None
         assert widget.rotation_snap_angle == 15
-        assert widget.snap_state == {
-            'is_snapped': False,
-            'last_position': None,
-            'last_size': None
-        }
+        assert widget.snap_state == {"is_snapped": False, "last_position": None, "last_size": None}
 
     def test_rotation_mode_is_mutable(self, qtbot):
         """Test that rotation mode can be toggled"""
@@ -72,7 +69,7 @@ class TestResizeElementNoSnap:
 
         elem = ImageData(image_path="test.jpg", x=100, y=100, width=200, height=150)
         widget.selected_element = elem
-        widget.resize_handle = 'se'
+        widget.resize_handle = "se"
         widget.resize_start_pos = (100, 100)
         widget.resize_start_size = (200, 150)
 
@@ -89,7 +86,7 @@ class TestResizeElementNoSnap:
 
         elem = ImageData(image_path="test.jpg", x=100, y=100, width=200, height=150)
         widget.selected_element = elem
-        widget.resize_handle = 'nw'
+        widget.resize_handle = "nw"
         widget.resize_start_pos = (100, 100)
         widget.resize_start_size = (200, 150)
 
@@ -106,7 +103,7 @@ class TestResizeElementNoSnap:
 
         elem = ImageData(image_path="test.jpg", x=100, y=100, width=200, height=150)
         widget.selected_element = elem
-        widget.resize_handle = 'ne'
+        widget.resize_handle = "ne"
         widget.resize_start_pos = (100, 100)
         widget.resize_start_size = (200, 150)
 
@@ -123,7 +120,7 @@ class TestResizeElementNoSnap:
 
         elem = ImageData(image_path="test.jpg", x=100, y=100, width=200, height=150)
         widget.selected_element = elem
-        widget.resize_handle = 'sw'
+        widget.resize_handle = "sw"
         widget.resize_start_pos = (100, 100)
         widget.resize_start_size = (200, 150)
 
@@ -140,7 +137,7 @@ class TestResizeElementNoSnap:
 
         elem = ImageData(image_path="test.jpg", x=100, y=100, width=50, height=50)
         widget.selected_element = elem
-        widget.resize_handle = 'se'
+        widget.resize_handle = "se"
         widget.resize_start_pos = (100, 100)
         widget.resize_start_size = (50, 50)
 
@@ -157,7 +154,7 @@ class TestResizeElementNoSnap:
 
         elem = ImageData(image_path="test.jpg", x=100, y=100, width=200, height=150)
         widget.selected_element = elem
-        widget.resize_handle = 'se'
+        widget.resize_handle = "se"
         # Don't set resize_start_pos or resize_start_size
 
         original_pos = elem.position
@@ -185,7 +182,7 @@ class TestResizeElementWithSnap:
         elem._parent_page = page
 
         widget.selected_element = elem
-        widget.resize_handle = 'se'
+        widget.resize_handle = "se"
         widget.resize_start_pos = (100, 100)
         widget.resize_start_size = (200, 150)
 
@@ -208,7 +205,7 @@ class TestResizeElementWithSnap:
         params = call_args[0][0]
         assert params.dx == 50
         assert params.dy == 30
-        assert params.resize_handle == 'se'
+        assert params.resize_handle == "se"
 
         # Verify element was updated
         assert elem.size == (250, 180)
@@ -220,7 +217,7 @@ class TestResizeElementWithSnap:
 
         elem = ImageData(image_path="test.jpg", x=100, y=100, width=200, height=150)
         widget.selected_element = elem
-        widget.resize_handle = 'se'
+        widget.resize_handle = "se"
         widget.resize_start_pos = (100, 100)
         widget.resize_start_size = (200, 150)
 
@@ -241,7 +238,7 @@ class TestResizeElementWithSnap:
         elem._parent_page = page
 
         widget.selected_element = elem
-        widget.resize_handle = 'se'
+        widget.resize_handle = "se"
         widget.resize_start_pos = (100, 100)
         widget.resize_start_size = (50, 50)
 
@@ -344,20 +341,20 @@ class TestManipulationStateManagement:
         widget = TestManipulationWidget()
         qtbot.addWidget(widget)
 
-        assert 'is_snapped' in widget.snap_state
-        assert 'last_position' in widget.snap_state
-        assert 'last_size' in widget.snap_state
+        assert "is_snapped" in widget.snap_state
+        assert "last_position" in widget.snap_state
+        assert "last_size" in widget.snap_state
 
     def test_resize_state_can_be_set(self, qtbot):
         """Test resize state variables can be set"""
         widget = TestManipulationWidget()
         qtbot.addWidget(widget)
 
-        widget.resize_handle = 'nw'
+        widget.resize_handle = "nw"
         widget.resize_start_pos = (10, 20)
         widget.resize_start_size = (100, 200)
 
-        assert widget.resize_handle == 'nw'
+        assert widget.resize_handle == "nw"
         assert widget.resize_start_pos == (10, 20)
         assert widget.resize_start_size == (100, 200)
 
diff --git a/tests/test_element_maximizer.py b/tests/test_element_maximizer.py
index 72c8191..e8497dc 100644
--- a/tests/test_element_maximizer.py
+++ b/tests/test_element_maximizer.py
@@ -258,6 +258,7 @@ class TestElementMaximizer:
     def test_maximize_empty_elements(self):
         """Test maximize with empty element list."""
         from pyPhotoAlbum.alignment import AlignmentManager
+
         result = AlignmentManager.maximize_pattern([], (200.0, 200.0))
         assert result == []
 
diff --git a/tests/test_element_ops_mixin.py b/tests/test_element_ops_mixin.py
index dcae6b4..34340ff 100755
--- a/tests/test_element_ops_mixin.py
+++ b/tests/test_element_ops_mixin.py
@@ -43,11 +43,11 @@ class TestElementWindow(ElementOperationsMixin, AssetPathMixin, QMainWindow):
     def require_page(self):
         """Track require_page calls"""
         self._require_page_called = True
-        return self._current_page is not None if hasattr(self, '_current_page') else False
+        return self._current_page is not None if hasattr(self, "_current_page") else False
 
     def get_current_page(self):
         """Return mock current page"""
-        if hasattr(self, '_current_page'):
+        if hasattr(self, "_current_page"):
             return self._current_page
         return None
 
@@ -71,8 +71,8 @@ class TestElementWindow(ElementOperationsMixin, AssetPathMixin, QMainWindow):
 class TestAddImage:
     """Test add_image method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.element_ops.QFileDialog.getOpenFileName')
-    @patch('pyPhotoAlbum.mixins.operations.element_ops.get_image_dimensions')
+    @patch("pyPhotoAlbum.mixins.operations.element_ops.QFileDialog.getOpenFileName")
+    @patch("pyPhotoAlbum.mixins.operations.element_ops.get_image_dimensions")
     def test_add_image_success(self, mock_get_dims, mock_file_dialog, qtbot):
         """Test successfully adding an image"""
         window = TestElementWindow()
@@ -106,7 +106,7 @@ class TestAddImage:
         assert window._update_view_called
         assert "added image" in window._status_message.lower()
 
-    @patch('pyPhotoAlbum.mixins.operations.element_ops.QFileDialog.getOpenFileName')
+    @patch("pyPhotoAlbum.mixins.operations.element_ops.QFileDialog.getOpenFileName")
     def test_add_image_cancelled(self, mock_file_dialog, qtbot):
         """Test cancelling image selection"""
         window = TestElementWindow()
@@ -139,8 +139,8 @@ class TestAddImage:
         assert window._require_page_called
         assert not window._update_view_called
 
-    @patch('pyPhotoAlbum.mixins.operations.element_ops.QFileDialog.getOpenFileName')
-    @patch('pyPhotoAlbum.mixins.operations.element_ops.get_image_dimensions')
+    @patch("pyPhotoAlbum.mixins.operations.element_ops.QFileDialog.getOpenFileName")
+    @patch("pyPhotoAlbum.mixins.operations.element_ops.get_image_dimensions")
     def test_add_image_scales_large_image(self, mock_get_dims, mock_file_dialog, qtbot):
         """Test that large images are scaled down"""
         window = TestElementWindow()
@@ -164,8 +164,8 @@ class TestAddImage:
         # Image should be added (scaled down by get_image_dimensions)
         assert window._update_view_called
 
-    @patch('pyPhotoAlbum.mixins.operations.element_ops.QFileDialog.getOpenFileName')
-    @patch('pyPhotoAlbum.mixins.operations.element_ops.get_image_dimensions')
+    @patch("pyPhotoAlbum.mixins.operations.element_ops.QFileDialog.getOpenFileName")
+    @patch("pyPhotoAlbum.mixins.operations.element_ops.get_image_dimensions")
     def test_add_image_fallback_dimensions(self, mock_get_dims, mock_file_dialog, qtbot):
         """Test fallback dimensions when get_image_dimensions returns None"""
         window = TestElementWindow()
@@ -294,8 +294,8 @@ class TestAddPlaceholder:
 class TestElementOperationsIntegration:
     """Test integration between element operations"""
 
-    @patch('pyPhotoAlbum.mixins.operations.element_ops.QFileDialog.getOpenFileName')
-    @patch('pyPhotoAlbum.mixins.operations.element_ops.get_image_dimensions')
+    @patch("pyPhotoAlbum.mixins.operations.element_ops.QFileDialog.getOpenFileName")
+    @patch("pyPhotoAlbum.mixins.operations.element_ops.get_image_dimensions")
     def test_add_multiple_elements(self, mock_get_dims, mock_file_dialog, qtbot):
         """Test adding multiple different element types"""
         window = TestElementWindow()
@@ -326,8 +326,8 @@ class TestElementOperationsIntegration:
         # Should have added all three elements
         assert window._update_view_called
 
-    @patch('pyPhotoAlbum.mixins.operations.element_ops.QFileDialog.getOpenFileName')
-    @patch('pyPhotoAlbum.mixins.operations.element_ops.get_image_dimensions')
+    @patch("pyPhotoAlbum.mixins.operations.element_ops.QFileDialog.getOpenFileName")
+    @patch("pyPhotoAlbum.mixins.operations.element_ops.get_image_dimensions")
     def test_add_image_with_undo(self, mock_get_dims, mock_file_dialog, qtbot):
         """Test that adding image can be undone"""
         window = TestElementWindow()
diff --git a/tests/test_element_selection_mixin.py b/tests/test_element_selection_mixin.py
index e80a978..464ef03 100755
--- a/tests/test_element_selection_mixin.py
+++ b/tests/test_element_selection_mixin.py
@@ -23,19 +23,19 @@ def mock_page_renderer():
 
     # Mock coordinate conversion methods
     def page_to_screen(x, y):
-        return (renderer.screen_x + x * renderer.zoom,
-                renderer.screen_y + y * renderer.zoom)
+        return (renderer.screen_x + x * renderer.zoom, renderer.screen_y + y * renderer.zoom)
 
     def screen_to_page(x, y):
-        return ((x - renderer.screen_x) / renderer.zoom,
-                (y - renderer.screen_y) / renderer.zoom)
+        return ((x - renderer.screen_x) / renderer.zoom, (y - renderer.screen_y) / renderer.zoom)
 
     def is_point_in_page(x, y):
         # Simple bounds check (assume 210mm x 297mm page at 96 DPI)
         page_width_px = 210 * 96 / 25.4
         page_height_px = 297 * 96 / 25.4
-        return (renderer.screen_x <= x <= renderer.screen_x + page_width_px * renderer.zoom and
-                renderer.screen_y <= y <= renderer.screen_y + page_height_px * renderer.zoom)
+        return (
+            renderer.screen_x <= x <= renderer.screen_x + page_width_px * renderer.zoom
+            and renderer.screen_y <= y <= renderer.screen_y + page_height_px * renderer.zoom
+        )
 
     renderer.page_to_screen = page_to_screen
     renderer.screen_to_page = screen_to_page
@@ -47,6 +47,7 @@ def mock_page_renderer():
 # Create a minimal test widget class
 class TestSelectionWidget(ElementSelectionMixin, QOpenGLWidget):
     """Test widget combining ElementSelectionMixin with QOpenGLWidget"""
+
     def __init__(self):
         super().__init__()
         self._page_renderers = []
@@ -60,7 +61,7 @@ class TestElementSelectionInitialization:
         widget = TestSelectionWidget()
         qtbot.addWidget(widget)
 
-        assert hasattr(widget, 'selected_elements')
+        assert hasattr(widget, "selected_elements")
         assert isinstance(widget.selected_elements, set)
         assert len(widget.selected_elements) == 0
 
@@ -172,8 +173,8 @@ class TestGetElementAt:
 
         assert result is not None
         assert result == elem
-        assert hasattr(result, '_page_renderer')
-        assert hasattr(result, '_parent_page')
+        assert hasattr(result, "_page_renderer")
+        assert hasattr(result, "_parent_page")
 
     def test_get_element_at_finds_topmost_element(self, qtbot, mock_page_renderer):
         """Test _get_element_at returns topmost element when overlapping"""
@@ -246,8 +247,8 @@ class TestGetElementAt:
         # Screen coords: (50 + 200, 50 + 175) = (250, 225)
         result = widget._get_element_at(250, 225)
         assert result == elem
-        assert hasattr(result, '_page_renderer')
-        assert hasattr(result, '_parent_page')
+        assert hasattr(result, "_page_renderer")
+        assert hasattr(result, "_parent_page")
 
     def test_get_element_at_rotated_element_outside(self, qtbot, mock_page_renderer):
         """Test _get_element_at correctly rejects clicks outside rotated element"""
@@ -288,8 +289,8 @@ class TestGetElementAt:
         # Should be able to select the element even though it's off the page
         assert result is not None
         assert result == elem
-        assert hasattr(result, '_page_renderer')
-        assert hasattr(result, '_parent_page')
+        assert hasattr(result, "_page_renderer")
+        assert hasattr(result, "_parent_page")
 
 
 class TestGetResizeHandleAt:
@@ -330,6 +331,7 @@ class TestGetResizeHandleAt:
         # Mock window with project
         from pyPhotoAlbum.project import Project, Page
         from pyPhotoAlbum.page_layout import PageLayout
+
         mock_window = Mock()
         mock_window.project = Project(name="Test")
         page = Page(layout=PageLayout(width=210, height=297), page_number=1)
@@ -351,6 +353,7 @@ class TestGetResizeHandleAt:
         # Mock window with project
         from pyPhotoAlbum.project import Project, Page
         from pyPhotoAlbum.page_layout import PageLayout
+
         mock_window = Mock()
         mock_window.project = Project(name="Test")
         page = Page(layout=PageLayout(width=210, height=297), page_number=1)
@@ -359,7 +362,7 @@ class TestGetResizeHandleAt:
 
         # Click on NW handle (screen: 50 + 100 = 150, 50 + 100 = 150)
         result = widget._get_resize_handle_at(150, 150)
-        assert result == 'nw'
+        assert result == "nw"
 
     def test_get_resize_handle_detects_all_corners(self, qtbot, mock_page_renderer):
         """Test _get_resize_handle_at detects all four corners"""
@@ -373,6 +376,7 @@ class TestGetResizeHandleAt:
         # Mock window
         from pyPhotoAlbum.project import Project, Page
         from pyPhotoAlbum.page_layout import PageLayout
+
         mock_window = Mock()
         mock_window.project = Project(name="Test")
         page = Page(layout=PageLayout(width=210, height=297), page_number=1)
@@ -380,16 +384,16 @@ class TestGetResizeHandleAt:
         widget.window = Mock(return_value=mock_window)
 
         # NW corner (screen: 50 + 100 = 150, 50 + 100 = 150)
-        assert widget._get_resize_handle_at(150, 150) == 'nw'
+        assert widget._get_resize_handle_at(150, 150) == "nw"
 
         # NE corner (screen: 50 + 300 = 350, 50 + 100 = 150)
-        assert widget._get_resize_handle_at(350, 150) == 'ne'
+        assert widget._get_resize_handle_at(350, 150) == "ne"
 
         # SW corner (screen: 50 + 100 = 150, 50 + 250 = 300)
-        assert widget._get_resize_handle_at(150, 300) == 'sw'
+        assert widget._get_resize_handle_at(150, 300) == "sw"
 
         # SE corner (screen: 50 + 300 = 350, 50 + 250 = 300)
-        assert widget._get_resize_handle_at(350, 300) == 'se'
+        assert widget._get_resize_handle_at(350, 300) == "se"
 
     def test_get_resize_handle_returns_none_for_center(self, qtbot, mock_page_renderer):
         """Test _get_resize_handle_at returns None for element center"""
@@ -403,6 +407,7 @@ class TestGetResizeHandleAt:
         # Mock window
         from pyPhotoAlbum.project import Project, Page
         from pyPhotoAlbum.page_layout import PageLayout
+
         mock_window = Mock()
         mock_window.project = Project(name="Test")
         page = Page(layout=PageLayout(width=210, height=297), page_number=1)
@@ -426,6 +431,7 @@ class TestGetResizeHandleAt:
         # Mock window
         from pyPhotoAlbum.project import Project, Page
         from pyPhotoAlbum.page_layout import PageLayout
+
         mock_window = Mock()
         mock_window.project = Project(name="Test")
         page = Page(layout=PageLayout(width=210, height=297), page_number=1)
@@ -436,7 +442,7 @@ class TestGetResizeHandleAt:
         # For rotated element, the handle positions are transformed
         result = widget._get_resize_handle_at(150, 150)
         # Should detect a handle (exact handle depends on rotation transform)
-        assert result is None or result in ['nw', 'ne', 'sw', 'se']
+        assert result is None or result in ["nw", "ne", "sw", "se"]
 
     def test_get_resize_handle_rotated_90_degrees(self, qtbot, mock_page_renderer):
         """Test _get_resize_handle_at handles 90-degree rotated elements"""
@@ -451,6 +457,7 @@ class TestGetResizeHandleAt:
         # Mock window
         from pyPhotoAlbum.project import Project, Page
         from pyPhotoAlbum.page_layout import PageLayout
+
         mock_window = Mock()
         mock_window.project = Project(name="Test")
         page = Page(layout=PageLayout(width=210, height=297), page_number=1)
@@ -460,7 +467,7 @@ class TestGetResizeHandleAt:
         # Test clicking at various positions - rotation code should handle them
         # Just verify the method runs without crashing
         result = widget._get_resize_handle_at(200, 200)
-        assert result is None or result in ['nw', 'ne', 'sw', 'se']
+        assert result is None or result in ["nw", "ne", "sw", "se"]
 
 
 class TestMultiSelect:
diff --git a/tests/test_embedded_templates.py b/tests/test_embedded_templates.py
index 18b14a0..eb04c4b 100755
--- a/tests/test_embedded_templates.py
+++ b/tests/test_embedded_templates.py
@@ -15,21 +15,18 @@ def test_embed_template_in_project():
     """Test embedding a template in a project"""
     # Create a project
     project = Project(name="Test Project")
-    
+
     # Create a template manager with the project
     template_manager = TemplateManager(project=project)
-    
+
     # Create a simple template
     template = Template(name="Test Template", description="A test template")
-    placeholder = PlaceholderData(
-        placeholder_type="image",
-        x=10, y=10, width=100, height=100
-    )
+    placeholder = PlaceholderData(placeholder_type="image", x=10, y=10, width=100, height=100)
     template.add_element(placeholder)
-    
+
     # Embed the template
     template_manager.embed_template(template)
-    
+
     # Verify it's embedded
     assert "Test Template" in project.embedded_templates
     assert project.embedded_templates["Test Template"]["name"] == "Test Template"
@@ -40,22 +37,19 @@ def test_load_embedded_template():
     """Test loading an embedded template"""
     # Create a project
     project = Project(name="Test Project")
-    
+
     # Create a template manager with the project
     template_manager = TemplateManager(project=project)
-    
+
     # Create and embed a template
     template = Template(name="Test Template", description="A test template")
-    placeholder = PlaceholderData(
-        placeholder_type="image",
-        x=10, y=10, width=100, height=100
-    )
+    placeholder = PlaceholderData(placeholder_type="image", x=10, y=10, width=100, height=100)
     template.add_element(placeholder)
     template_manager.embed_template(template)
-    
+
     # Load the embedded template
     loaded_template = template_manager.load_template("Test Template")
-    
+
     assert loaded_template.name == "Test Template"
     assert loaded_template.description == "A test template"
     assert len(loaded_template.elements) == 1
@@ -65,18 +59,18 @@ def test_list_embedded_templates():
     """Test listing embedded templates alongside filesystem templates"""
     # Create a project
     project = Project(name="Test Project")
-    
+
     # Create a template manager with the project
     template_manager = TemplateManager(project=project)
-    
+
     # Embed some templates
     for i in range(3):
         template = Template(name=f"Embedded_{i}")
         template_manager.embed_template(template)
-    
+
     # List all templates
     templates = template_manager.list_templates()
-    
+
     # Check embedded templates are listed with prefix
     embedded_templates = [t for t in templates if t.startswith("[Embedded]")]
     assert len(embedded_templates) == 3
@@ -89,14 +83,14 @@ def test_embedded_template_priority():
     """Test that embedded templates take priority over filesystem templates"""
     # Create a project
     project = Project(name="Test Project")
-    
+
     # Create a template manager with the project
     template_manager = TemplateManager(project=project)
-    
+
     # Embed a template with a common name
     embedded_template = Template(name="Common", description="Embedded version")
     template_manager.embed_template(embedded_template)
-    
+
     # Load by name without prefix (should get embedded version)
     loaded = template_manager.load_template("Common")
     assert loaded.description == "Embedded version"
@@ -106,22 +100,19 @@ def test_serialize_project_with_embedded_templates():
     """Test serializing a project with embedded templates"""
     # Create a project
     project = Project(name="Test Project")
-    
+
     # Create a template manager with the project
     template_manager = TemplateManager(project=project)
-    
+
     # Create and embed a template
     template = Template(name="Test Template", description="A test template")
-    placeholder = PlaceholderData(
-        placeholder_type="image",
-        x=10, y=10, width=100, height=100
-    )
+    placeholder = PlaceholderData(placeholder_type="image", x=10, y=10, width=100, height=100)
     template.add_element(placeholder)
     template_manager.embed_template(template)
-    
+
     # Serialize the project
     serialized = project.serialize()
-    
+
     # Verify embedded templates are in serialization
     assert "embedded_templates" in serialized
     assert "Test Template" in serialized["embedded_templates"]
@@ -133,26 +124,23 @@ def test_deserialize_project_with_embedded_templates():
     # Create a project with embedded template
     project = Project(name="Test Project")
     template_manager = TemplateManager(project=project)
-    
+
     template = Template(name="Test Template", description="A test template")
-    placeholder = PlaceholderData(
-        placeholder_type="image",
-        x=10, y=10, width=100, height=100
-    )
+    placeholder = PlaceholderData(placeholder_type="image", x=10, y=10, width=100, height=100)
     template.add_element(placeholder)
     template_manager.embed_template(template)
-    
+
     # Serialize the project
     serialized = project.serialize()
-    
+
     # Create a new project and deserialize
     new_project = Project(name="New Project")
     new_project.deserialize(serialized)
-    
+
     # Verify embedded templates were restored
     assert "Test Template" in new_project.embedded_templates
     assert new_project.embedded_templates["Test Template"]["name"] == "Test Template"
-    
+
     # Verify we can load the template from the new project
     new_template_manager = TemplateManager(project=new_project)
     loaded_template = new_template_manager.load_template("Test Template")
@@ -166,21 +154,18 @@ def test_auto_embed_on_apply():
     project = Project(name="Test Project")
     page = Page()
     project.add_page(page)
-    
+
     # Create a template manager with the project
     template_manager = TemplateManager(project=project)
-    
+
     # Create a template (not embedded yet)
     template = Template(name="Auto Embed Test", description="Should auto-embed")
-    placeholder = PlaceholderData(
-        placeholder_type="image",
-        x=10, y=10, width=100, height=100
-    )
+    placeholder = PlaceholderData(placeholder_type="image", x=10, y=10, width=100, height=100)
     template.add_element(placeholder)
-    
+
     # Apply template with auto_embed=True (default)
     template_manager.apply_template_to_page(template, page)
-    
+
     # Verify template was auto-embedded
     assert "Auto Embed Test" in project.embedded_templates
 
@@ -189,21 +174,18 @@ def test_auto_embed_on_create_page():
     """Test that templates are automatically embedded when creating pages"""
     # Create a project
     project = Project(name="Test Project")
-    
+
     # Create a template manager with the project
     template_manager = TemplateManager(project=project)
-    
+
     # Create a template (not embedded yet)
     template = Template(name="Auto Embed Page Test", description="Should auto-embed")
-    placeholder = PlaceholderData(
-        placeholder_type="image",
-        x=10, y=10, width=100, height=100
-    )
+    placeholder = PlaceholderData(placeholder_type="image", x=10, y=10, width=100, height=100)
     template.add_element(placeholder)
-    
+
     # Create page from template with auto_embed=True (default)
     page = template_manager.create_page_from_template(template, page_number=1)
-    
+
     # Verify template was auto-embedded
     assert "Auto Embed Page Test" in project.embedded_templates
 
@@ -212,19 +194,19 @@ def test_delete_embedded_template():
     """Test deleting an embedded template"""
     # Create a project
     project = Project(name="Test Project")
-    
+
     # Create a template manager with the project
     template_manager = TemplateManager(project=project)
-    
+
     # Embed a template
     template = Template(name="To Delete")
     template_manager.embed_template(template)
-    
+
     assert "To Delete" in project.embedded_templates
-    
+
     # Delete the embedded template
     template_manager.delete_template("[Embedded] To Delete")
-    
+
     assert "To Delete" not in project.embedded_templates
 
 
@@ -232,22 +214,19 @@ def test_embedded_template_with_text():
     """Test embedding template with text elements"""
     # Create a project
     project = Project(name="Test Project")
-    
+
     # Create a template manager with the project
     template_manager = TemplateManager(project=project)
-    
+
     # Create a template with text
     template = Template(name="Text Template")
-    textbox = TextBoxData(
-        text_content="Sample Text",
-        x=10, y=10, width=200, height=50
-    )
+    textbox = TextBoxData(text_content="Sample Text", x=10, y=10, width=200, height=50)
     template.add_element(textbox)
-    
+
     # Embed and reload
     template_manager.embed_template(template)
     loaded = template_manager.load_template("Text Template")
-    
+
     assert len(loaded.elements) == 1
     assert isinstance(loaded.elements[0], TextBoxData)
     assert loaded.elements[0].text_content == "Sample Text"
@@ -258,46 +237,38 @@ def test_roundtrip_serialization():
     # Create a project with pages and embedded template
     project = Project(name="Roundtrip Test")
     template_manager = TemplateManager(project=project)
-    
+
     # Create a template
     template = Template(name="Roundtrip Template", page_size_mm=(200, 300))
-    placeholder1 = PlaceholderData(
-        placeholder_type="image",
-        x=10, y=10, width=80, height=80
-    )
-    placeholder2 = PlaceholderData(
-        placeholder_type="image",
-        x=110, y=10, width=80, height=80
-    )
+    placeholder1 = PlaceholderData(placeholder_type="image", x=10, y=10, width=80, height=80)
+    placeholder2 = PlaceholderData(placeholder_type="image", x=110, y=10, width=80, height=80)
     template.add_element(placeholder1)
     template.add_element(placeholder2)
-    
+
     # Create a page from this template
     page = template_manager.create_page_from_template(template, page_number=1)
     project.add_page(page)
-    
+
     # Serialize
     serialized = project.serialize()
-    
+
     # Create new project and deserialize
     new_project = Project(name="New Roundtrip")
     new_project.deserialize(serialized)
-    
+
     # Verify embedded template
     assert "Roundtrip Template" in new_project.embedded_templates
-    
+
     # Verify we can use the template
     new_template_manager = TemplateManager(project=new_project)
     loaded_template = new_template_manager.load_template("Roundtrip Template")
-    
+
     assert loaded_template.name == "Roundtrip Template"
     assert loaded_template.page_size_mm == (200, 300)
     assert len(loaded_template.elements) == 2
-    
+
     # Create another page from the loaded template
     new_page = new_template_manager.create_page_from_template(
-        loaded_template, 
-        page_number=2,
-        auto_embed=False  # Don't embed again
+        loaded_template, page_number=2, auto_embed=False  # Don't embed again
     )
     assert len(new_page.layout.elements) == 2
diff --git a/tests/test_gl_widget_integration.py b/tests/test_gl_widget_integration.py
index 2de157a..e4cf8d6 100755
--- a/tests/test_gl_widget_integration.py
+++ b/tests/test_gl_widget_integration.py
@@ -21,13 +21,13 @@ class TestGLWidgetInitialization:
         qtbot.addWidget(widget)
 
         # Verify mixin state is initialized
-        assert hasattr(widget, 'zoom_level')
-        assert hasattr(widget, 'pan_offset')
-        assert hasattr(widget, 'selected_elements')
-        assert hasattr(widget, 'drag_start_pos')
-        assert hasattr(widget, 'is_dragging')
-        assert hasattr(widget, 'is_panning')
-        assert hasattr(widget, 'rotation_mode')
+        assert hasattr(widget, "zoom_level")
+        assert hasattr(widget, "pan_offset")
+        assert hasattr(widget, "selected_elements")
+        assert hasattr(widget, "drag_start_pos")
+        assert hasattr(widget, "is_dragging")
+        assert hasattr(widget, "is_panning")
+        assert hasattr(widget, "rotation_mode")
 
     def test_gl_widget_accepts_drops(self, qtbot):
         """Test GLWidget is configured to accept drops"""
@@ -105,7 +105,7 @@ class TestGLWidgetMixinIntegration:
             QPointF(75, 75),
             Qt.MouseButton.LeftButton,
             Qt.MouseButton.LeftButton,
-            Qt.KeyboardModifier.NoModifier
+            Qt.KeyboardModifier.NoModifier,
         )
 
         widget.mousePressEvent(event)
@@ -125,7 +125,7 @@ class TestGLWidgetMixinIntegration:
         # Begin operation (should be tracked for undo)
         widget._begin_move(element)
         assert widget._interaction_state.element is not None
-        assert widget._interaction_state.interaction_type == 'move'
+        assert widget._interaction_state.interaction_type == "move"
         assert widget._interaction_state.position == (100, 100)
 
         # End operation
@@ -152,11 +152,8 @@ class TestGLWidgetKeyEvents:
 
         # Create key press event for Escape
         from PyQt6.QtGui import QKeyEvent
-        event = QKeyEvent(
-            QKeyEvent.Type.KeyPress,
-            Qt.Key.Key_Escape,
-            Qt.KeyboardModifier.NoModifier
-        )
+
+        event = QKeyEvent(QKeyEvent.Type.KeyPress, Qt.Key.Key_Escape, Qt.KeyboardModifier.NoModifier)
 
         widget.keyPressEvent(event)
 
@@ -186,11 +183,8 @@ class TestGLWidgetKeyEvents:
 
         # Create key press event for Tab
         from PyQt6.QtGui import QKeyEvent
-        event = QKeyEvent(
-            QKeyEvent.Type.KeyPress,
-            Qt.Key.Key_Tab,
-            Qt.KeyboardModifier.NoModifier
-        )
+
+        event = QKeyEvent(QKeyEvent.Type.KeyPress, Qt.Key.Key_Tab, Qt.KeyboardModifier.NoModifier)
 
         widget.keyPressEvent(event)
 
@@ -220,11 +214,8 @@ class TestGLWidgetKeyEvents:
 
         # Create key press event for Delete
         from PyQt6.QtGui import QKeyEvent
-        event = QKeyEvent(
-            QKeyEvent.Type.KeyPress,
-            Qt.Key.Key_Delete,
-            Qt.KeyboardModifier.NoModifier
-        )
+
+        event = QKeyEvent(QKeyEvent.Type.KeyPress, Qt.Key.Key_Delete, Qt.KeyboardModifier.NoModifier)
 
         widget.keyPressEvent(event)
 
@@ -257,7 +248,7 @@ class TestGLWidgetWithProject:
 
         # Verify we can access project through widget
         main_window = widget.window()
-        assert hasattr(main_window, 'project')
+        assert hasattr(main_window, "project")
         assert main_window.project.name == "Test Project"
         assert len(main_window.project.pages) == 1
         assert len(main_window.project.pages[0].layout.elements) == 1
@@ -321,6 +312,7 @@ class TestGLWidgetOpenGL:
 
         # Should have NoPartialUpdate set
         from PyQt6.QtOpenGLWidgets import QOpenGLWidget
+
         assert widget.updateBehavior() == QOpenGLWidget.UpdateBehavior.NoPartialUpdate
 
 
diff --git a/tests/test_image_pan_mixin.py b/tests/test_image_pan_mixin.py
index cc81232..0743195 100755
--- a/tests/test_image_pan_mixin.py
+++ b/tests/test_image_pan_mixin.py
@@ -14,6 +14,7 @@ from pyPhotoAlbum.models import ImageData, PlaceholderData
 # Create test widget combining necessary mixins
 class TestImagePanWidget(ImagePanMixin, ElementSelectionMixin, ViewportMixin, QOpenGLWidget):
     """Test widget combining image pan, selection, and viewport mixins"""
+
     def __init__(self):
         super().__init__()
         self.drag_start_pos = None
diff --git a/tests/test_interaction_command_builders.py b/tests/test_interaction_command_builders.py
index 2b4dcc8..c7933ef 100644
--- a/tests/test_interaction_command_builders.py
+++ b/tests/test_interaction_command_builders.py
@@ -8,7 +8,7 @@ from pyPhotoAlbum.mixins.interaction_command_builders import (
     MoveCommandBuilder,
     ResizeCommandBuilder,
     RotateCommandBuilder,
-    ImagePanCommandBuilder
+    ImagePanCommandBuilder,
 )
 from pyPhotoAlbum.mixins.interaction_validators import InteractionChangeDetector
 
@@ -22,7 +22,7 @@ class TestMoveCommandBuilder:
         element = Mock()
         element.position = (10.0, 10.0)
 
-        start_state = {'position': (0.0, 0.0)}
+        start_state = {"position": (0.0, 0.0)}
 
         assert builder.can_build(element, start_state)
 
@@ -32,7 +32,7 @@ class TestMoveCommandBuilder:
         element = Mock()
         element.position = (0.05, 0.05)
 
-        start_state = {'position': (0.0, 0.0)}
+        start_state = {"position": (0.0, 0.0)}
 
         assert not builder.can_build(element, start_state)
 
@@ -52,7 +52,7 @@ class TestMoveCommandBuilder:
         element = Mock()
         element.position = (10.0, 10.0)
 
-        start_state = {'position': (0.0, 0.0)}
+        start_state = {"position": (0.0, 0.0)}
 
         command = builder.build(element, start_state)
 
@@ -65,7 +65,7 @@ class TestMoveCommandBuilder:
         element = Mock()
         element.position = (0.05, 0.05)
 
-        start_state = {'position': (0.0, 0.0)}
+        start_state = {"position": (0.0, 0.0)}
 
         command = builder.build(element, start_state)
 
@@ -82,10 +82,7 @@ class TestResizeCommandBuilder:
         element.position = (0.0, 0.0)
         element.size = (200.0, 200.0)
 
-        start_state = {
-            'position': (0.0, 0.0),
-            'size': (100.0, 100.0)
-        }
+        start_state = {"position": (0.0, 0.0), "size": (100.0, 100.0)}
 
         assert builder.can_build(element, start_state)
 
@@ -96,10 +93,7 @@ class TestResizeCommandBuilder:
         element.position = (10.0, 10.0)
         element.size = (100.0, 100.0)
 
-        start_state = {
-            'position': (0.0, 0.0),
-            'size': (100.0, 100.0)
-        }
+        start_state = {"position": (0.0, 0.0), "size": (100.0, 100.0)}
 
         assert builder.can_build(element, start_state)
 
@@ -110,10 +104,7 @@ class TestResizeCommandBuilder:
         element.position = (10.0, 10.0)
         element.size = (200.0, 200.0)
 
-        start_state = {
-            'position': (0.0, 0.0),
-            'size': (100.0, 100.0)
-        }
+        start_state = {"position": (0.0, 0.0), "size": (100.0, 100.0)}
 
         assert builder.can_build(element, start_state)
 
@@ -124,10 +115,7 @@ class TestResizeCommandBuilder:
         element.position = (0.0, 0.0)
         element.size = (100.0, 100.0)
 
-        start_state = {
-            'position': (0.0, 0.0),
-            'size': (100.0, 100.0)
-        }
+        start_state = {"position": (0.0, 0.0), "size": (100.0, 100.0)}
 
         assert not builder.can_build(element, start_state)
 
@@ -138,10 +126,7 @@ class TestResizeCommandBuilder:
         element.position = (10.0, 10.0)
         element.size = (200.0, 200.0)
 
-        start_state = {
-            'position': (0.0, 0.0),
-            'size': (100.0, 100.0)
-        }
+        start_state = {"position": (0.0, 0.0), "size": (100.0, 100.0)}
 
         command = builder.build(element, start_state)
 
@@ -158,7 +143,7 @@ class TestRotateCommandBuilder:
         element = Mock()
         element.rotation = 45.0
 
-        start_state = {'rotation': 0.0}
+        start_state = {"rotation": 0.0}
 
         assert builder.can_build(element, start_state)
 
@@ -168,7 +153,7 @@ class TestRotateCommandBuilder:
         element = Mock()
         element.rotation = 0.05
 
-        start_state = {'rotation': 0.0}
+        start_state = {"rotation": 0.0}
 
         assert not builder.can_build(element, start_state)
 
@@ -178,7 +163,7 @@ class TestRotateCommandBuilder:
         element = Mock()
         element.rotation = 45.0
 
-        start_state = {'rotation': 0.0}
+        start_state = {"rotation": 0.0}
 
         command = builder.build(element, start_state)
 
@@ -197,7 +182,7 @@ class TestImagePanCommandBuilder:
         element = Mock(spec=ImageData)
         element.crop_info = (0.1, 0.1, 0.9, 0.9)
 
-        start_state = {'crop_info': (0.0, 0.0, 1.0, 1.0)}
+        start_state = {"crop_info": (0.0, 0.0, 1.0, 1.0)}
 
         assert builder.can_build(element, start_state)
 
@@ -207,7 +192,7 @@ class TestImagePanCommandBuilder:
         element = Mock()
         element.crop_info = (0.1, 0.1, 0.9, 0.9)
 
-        start_state = {'crop_info': (0.0, 0.0, 1.0, 1.0)}
+        start_state = {"crop_info": (0.0, 0.0, 1.0, 1.0)}
 
         assert not builder.can_build(element, start_state)
 
@@ -219,7 +204,7 @@ class TestImagePanCommandBuilder:
         element = Mock(spec=ImageData)
         element.crop_info = (0.0001, 0.0001, 1.0, 1.0)
 
-        start_state = {'crop_info': (0.0, 0.0, 1.0, 1.0)}
+        start_state = {"crop_info": (0.0, 0.0, 1.0, 1.0)}
 
         assert not builder.can_build(element, start_state)
 
@@ -231,7 +216,7 @@ class TestImagePanCommandBuilder:
         element = Mock(spec=ImageData)
         element.crop_info = (0.1, 0.1, 0.9, 0.9)
 
-        start_state = {'crop_info': (0.0, 0.0, 1.0, 1.0)}
+        start_state = {"crop_info": (0.0, 0.0, 1.0, 1.0)}
 
         command = builder.build(element, start_state)
 
@@ -250,7 +235,7 @@ class TestCommandBuilderIntegration:
         element = Mock()
         element.position = (5.0, 5.0)
 
-        start_state = {'position': (0.0, 0.0)}
+        start_state = {"position": (0.0, 0.0)}
 
         # With high threshold, this should not build
         assert not builder.can_build(element, start_state)
@@ -261,7 +246,7 @@ class TestCommandBuilderIntegration:
         element = Mock()
         element.position = (10.0, 10.0)
 
-        start_state = {'position': (0.0, 0.0)}
+        start_state = {"position": (0.0, 0.0)}
 
         builder.build(element, start_state)
 
diff --git a/tests/test_interaction_command_factory.py b/tests/test_interaction_command_factory.py
index d924c1e..60c7837 100644
--- a/tests/test_interaction_command_factory.py
+++ b/tests/test_interaction_command_factory.py
@@ -4,10 +4,7 @@ Unit tests for interaction command factory.
 
 import pytest
 from unittest.mock import Mock
-from pyPhotoAlbum.mixins.interaction_command_factory import (
-    InteractionCommandFactory,
-    InteractionState
-)
+from pyPhotoAlbum.mixins.interaction_command_factory import InteractionCommandFactory, InteractionState
 from pyPhotoAlbum.mixins.interaction_command_builders import CommandBuilder
 
 
@@ -18,71 +15,49 @@ class TestInteractionState:
         """Test that InteractionState initializes correctly."""
         element = Mock()
         state = InteractionState(
-            element=element,
-            interaction_type='move',
-            position=(0.0, 0.0),
-            size=(100.0, 100.0),
-            rotation=0.0
+            element=element, interaction_type="move", position=(0.0, 0.0), size=(100.0, 100.0), rotation=0.0
         )
 
         assert state.element == element
-        assert state.interaction_type == 'move'
+        assert state.interaction_type == "move"
         assert state.position == (0.0, 0.0)
         assert state.size == (100.0, 100.0)
         assert state.rotation == 0.0
 
     def test_to_dict(self):
         """Test that to_dict returns correct dictionary."""
-        state = InteractionState(
-            position=(0.0, 0.0),
-            size=(100.0, 100.0)
-        )
+        state = InteractionState(position=(0.0, 0.0), size=(100.0, 100.0))
 
         result = state.to_dict()
 
-        assert result == {
-            'position': (0.0, 0.0),
-            'size': (100.0, 100.0)
-        }
+        assert result == {"position": (0.0, 0.0), "size": (100.0, 100.0)}
 
     def test_to_dict_excludes_none(self):
         """Test that to_dict excludes None values."""
-        state = InteractionState(
-            position=(0.0, 0.0),
-            size=None
-        )
+        state = InteractionState(position=(0.0, 0.0), size=None)
 
         result = state.to_dict()
 
-        assert 'position' in result
-        assert 'size' not in result
+        assert "position" in result
+        assert "size" not in result
 
     def test_is_valid_with_required_fields(self):
         """Test that is_valid returns True when required fields are present."""
         element = Mock()
-        state = InteractionState(
-            element=element,
-            interaction_type='move'
-        )
+        state = InteractionState(element=element, interaction_type="move")
 
         assert state.is_valid()
 
     def test_is_valid_without_element(self):
         """Test that is_valid returns False without element."""
-        state = InteractionState(
-            element=None,
-            interaction_type='move'
-        )
+        state = InteractionState(element=None, interaction_type="move")
 
         assert not state.is_valid()
 
     def test_is_valid_without_interaction_type(self):
         """Test that is_valid returns False without interaction_type."""
         element = Mock()
-        state = InteractionState(
-            element=element,
-            interaction_type=None
-        )
+        state = InteractionState(element=element, interaction_type=None)
 
         assert not state.is_valid()
 
@@ -90,11 +65,7 @@ class TestInteractionState:
         """Test that clear resets all fields."""
         element = Mock()
         state = InteractionState(
-            element=element,
-            interaction_type='move',
-            position=(0.0, 0.0),
-            size=(100.0, 100.0),
-            rotation=0.0
+            element=element, interaction_type="move", position=(0.0, 0.0), size=(100.0, 100.0), rotation=0.0
         )
 
         state.clear()
@@ -113,19 +84,19 @@ class TestInteractionCommandFactory:
         """Test that factory initializes with default builders."""
         factory = InteractionCommandFactory()
 
-        assert factory.has_builder('move')
-        assert factory.has_builder('resize')
-        assert factory.has_builder('rotate')
-        assert factory.has_builder('image_pan')
+        assert factory.has_builder("move")
+        assert factory.has_builder("resize")
+        assert factory.has_builder("rotate")
+        assert factory.has_builder("image_pan")
 
     def test_register_builder(self):
         """Test registering a custom builder."""
         factory = InteractionCommandFactory()
         custom_builder = Mock(spec=CommandBuilder)
 
-        factory.register_builder('custom', custom_builder)
+        factory.register_builder("custom", custom_builder)
 
-        assert factory.has_builder('custom')
+        assert factory.has_builder("custom")
 
     def test_get_supported_types(self):
         """Test getting list of supported types."""
@@ -133,10 +104,10 @@ class TestInteractionCommandFactory:
 
         types = factory.get_supported_types()
 
-        assert 'move' in types
-        assert 'resize' in types
-        assert 'rotate' in types
-        assert 'image_pan' in types
+        assert "move" in types
+        assert "resize" in types
+        assert "rotate" in types
+        assert "image_pan" in types
 
     def test_create_command_move(self):
         """Test creating a move command."""
@@ -144,9 +115,9 @@ class TestInteractionCommandFactory:
         element = Mock()
         element.position = (10.0, 10.0)
 
-        start_state = {'position': (0.0, 0.0)}
+        start_state = {"position": (0.0, 0.0)}
 
-        command = factory.create_command('move', element, start_state)
+        command = factory.create_command("move", element, start_state)
 
         assert command is not None
 
@@ -157,12 +128,9 @@ class TestInteractionCommandFactory:
         element.position = (10.0, 10.0)
         element.size = (200.0, 200.0)
 
-        start_state = {
-            'position': (0.0, 0.0),
-            'size': (100.0, 100.0)
-        }
+        start_state = {"position": (0.0, 0.0), "size": (100.0, 100.0)}
 
-        command = factory.create_command('resize', element, start_state)
+        command = factory.create_command("resize", element, start_state)
 
         assert command is not None
 
@@ -172,9 +140,9 @@ class TestInteractionCommandFactory:
         element = Mock()
         element.rotation = 45.0
 
-        start_state = {'rotation': 0.0}
+        start_state = {"rotation": 0.0}
 
-        command = factory.create_command('rotate', element, start_state)
+        command = factory.create_command("rotate", element, start_state)
 
         assert command is not None
 
@@ -183,7 +151,7 @@ class TestInteractionCommandFactory:
         factory = InteractionCommandFactory()
         element = Mock()
 
-        command = factory.create_command('unknown', element, {})
+        command = factory.create_command("unknown", element, {})
 
         assert command is None
         captured = capsys.readouterr()
@@ -195,9 +163,9 @@ class TestInteractionCommandFactory:
         element = Mock()
         element.position = (0.05, 0.05)
 
-        start_state = {'position': (0.0, 0.0)}
+        start_state = {"position": (0.0, 0.0)}
 
-        command = factory.create_command('move', element, start_state)
+        command = factory.create_command("move", element, start_state)
 
         assert command is None
 
@@ -211,12 +179,12 @@ class TestInteractionCommandFactory:
         custom_builder.can_build.return_value = True
         custom_builder.build.return_value = mock_command
 
-        factory.register_builder('custom', custom_builder)
+        factory.register_builder("custom", custom_builder)
 
         element = Mock()
-        start_state = {'position': (0.0, 0.0)}
+        start_state = {"position": (0.0, 0.0)}
 
-        command = factory.create_command('custom', element, start_state)
+        command = factory.create_command("custom", element, start_state)
 
         assert command == mock_command
         custom_builder.can_build.assert_called_once()
@@ -232,17 +200,9 @@ class TestInteractionStateIntegration:
         element = Mock()
         element.position = (10.0, 10.0)
 
-        state = InteractionState(
-            element=element,
-            interaction_type='move',
-            position=(0.0, 0.0)
-        )
+        state = InteractionState(element=element, interaction_type="move", position=(0.0, 0.0))
 
-        command = factory.create_command(
-            state.interaction_type,
-            state.element,
-            state.to_dict()
-        )
+        command = factory.create_command(state.interaction_type, state.element, state.to_dict())
 
         assert command is not None
 
@@ -254,7 +214,7 @@ class TestInteractionStateIntegration:
         # Begin interaction
         state = InteractionState()
         state.element = element
-        state.interaction_type = 'move'
+        state.interaction_type = "move"
         state.position = element.position
 
         assert state.is_valid()
@@ -264,11 +224,7 @@ class TestInteractionStateIntegration:
 
         # Create command
         factory = InteractionCommandFactory()
-        command = factory.create_command(
-            state.interaction_type,
-            state.element,
-            state.to_dict()
-        )
+        command = factory.create_command(state.interaction_type, state.element, state.to_dict())
 
         assert command is not None
 
diff --git a/tests/test_interaction_undo_mixin.py b/tests/test_interaction_undo_mixin.py
index d6a4c8f..f20dc52 100755
--- a/tests/test_interaction_undo_mixin.py
+++ b/tests/test_interaction_undo_mixin.py
@@ -29,8 +29,8 @@ class TestUndoableInteractionInitialization:
         qtbot.addWidget(widget)
 
         # Should have initialized tracking state object
-        assert hasattr(widget, '_interaction_state')
-        assert hasattr(widget, '_command_factory')
+        assert hasattr(widget, "_interaction_state")
+        assert hasattr(widget, "_command_factory")
 
         # State should be clear initially
         assert widget._interaction_state.element is None
@@ -53,7 +53,7 @@ class TestBeginMove:
         widget._begin_move(element)
 
         assert widget._interaction_state.element is element
-        assert widget._interaction_state.interaction_type == 'move'
+        assert widget._interaction_state.interaction_type == "move"
         assert widget._interaction_state.position == (100, 100)
         assert widget._interaction_state.size is None
         assert widget._interaction_state.rotation is None
@@ -87,7 +87,7 @@ class TestBeginResize:
         widget._begin_resize(element)
 
         assert widget._interaction_state.element is element
-        assert widget._interaction_state.interaction_type == 'resize'
+        assert widget._interaction_state.interaction_type == "resize"
         assert widget._interaction_state.position == (100, 100)
         assert widget._interaction_state.size == (200, 150)
         assert widget._interaction_state.rotation is None
@@ -107,7 +107,7 @@ class TestBeginRotate:
         widget._begin_rotate(element)
 
         assert widget._interaction_state.element is element
-        assert widget._interaction_state.interaction_type == 'rotate'
+        assert widget._interaction_state.interaction_type == "rotate"
         assert widget._interaction_state.position is None
         assert widget._interaction_state.size is None
         assert widget._interaction_state.rotation == 45.0
@@ -121,17 +121,12 @@ class TestBeginImagePan:
         widget = TestUndoableWidget()
         qtbot.addWidget(widget)
 
-        element = ImageData(
-            image_path="/test.jpg",
-            x=100, y=100,
-            width=200, height=150,
-            crop_info=(0.1, 0.2, 0.8, 0.7)
-        )
+        element = ImageData(image_path="/test.jpg", x=100, y=100, width=200, height=150, crop_info=(0.1, 0.2, 0.8, 0.7))
 
         widget._begin_image_pan(element)
 
         assert widget._interaction_state.element is element
-        assert widget._interaction_state.interaction_type == 'image_pan'
+        assert widget._interaction_state.interaction_type == "image_pan"
         assert widget._interaction_state.crop_info == (0.1, 0.2, 0.8, 0.7)
 
     def test_begin_image_pan_ignores_non_image(self, qtbot):
@@ -151,7 +146,7 @@ class TestBeginImagePan:
 class TestEndInteraction:
     """Test _end_interaction method"""
 
-    @patch('pyPhotoAlbum.commands.MoveElementCommand')
+    @patch("pyPhotoAlbum.commands.MoveElementCommand")
     def test_end_interaction_creates_move_command(self, mock_cmd_class, qtbot):
         """Test that ending move interaction creates MoveElementCommand"""
         widget = TestUndoableWidget()
@@ -177,7 +172,7 @@ class TestEndInteraction:
         mock_cmd_class.assert_called_once_with(element, (100, 100), (150, 160))
         assert mock_window.project.history.execute.called
 
-    @patch('pyPhotoAlbum.commands.ResizeElementCommand')
+    @patch("pyPhotoAlbum.commands.ResizeElementCommand")
     def test_end_interaction_creates_resize_command(self, mock_cmd_class, qtbot):
         """Test that ending resize interaction creates ResizeElementCommand"""
         widget = TestUndoableWidget()
@@ -204,12 +199,12 @@ class TestEndInteraction:
             element,
             (100, 100),  # old position
             (200, 150),  # old size
-            (90, 90),    # new position
-            (250, 200)   # new size
+            (90, 90),  # new position
+            (250, 200),  # new size
         )
         assert mock_window.project.history.execute.called
 
-    @patch('pyPhotoAlbum.commands.RotateElementCommand')
+    @patch("pyPhotoAlbum.commands.RotateElementCommand")
     def test_end_interaction_creates_rotate_command(self, mock_cmd_class, qtbot):
         """Test that ending rotate interaction creates RotateElementCommand"""
         widget = TestUndoableWidget()
@@ -235,7 +230,7 @@ class TestEndInteraction:
         mock_cmd_class.assert_called_once_with(element, 0, 90)
         assert mock_window.project.history.execute.called
 
-    @patch('pyPhotoAlbum.commands.AdjustImageCropCommand')
+    @patch("pyPhotoAlbum.commands.AdjustImageCropCommand")
     def test_end_interaction_creates_crop_command(self, mock_cmd_class, qtbot):
         """Test that ending image pan interaction creates AdjustImageCropCommand"""
         widget = TestUndoableWidget()
@@ -248,9 +243,11 @@ class TestEndInteraction:
 
         element = ImageData(
             image_path="/test.jpg",
-            x=100, y=100,
-            width=200, height=150,
-            crop_info=(0.0, 0.0, 1.0, 1.0)  # Tuple format used in code
+            x=100,
+            y=100,
+            width=200,
+            height=150,
+            crop_info=(0.0, 0.0, 1.0, 1.0),  # Tuple format used in code
         )
 
         widget._begin_image_pan(element)
@@ -391,12 +388,7 @@ class TestClearInteractionState:
         widget = TestUndoableWidget()
         qtbot.addWidget(widget)
 
-        element = ImageData(
-            image_path="/test.jpg",
-            x=100, y=100,
-            width=200, height=150,
-            crop_info=(0.0, 0.0, 1.0, 1.0)
-        )
+        element = ImageData(image_path="/test.jpg", x=100, y=100, width=200, height=150, crop_info=(0.0, 0.0, 1.0, 1.0))
 
         widget._begin_image_pan(element)
         # After begin_image_pan, crop_info should be stored
@@ -452,10 +444,10 @@ class TestInteractionEdgeCases:
         widget._begin_rotate(element)
 
         # Should have rotate state (last call wins)
-        assert widget._interaction_state.interaction_type == 'rotate'
+        assert widget._interaction_state.interaction_type == "rotate"
         assert widget._interaction_state.rotation == 0
 
-    @patch('pyPhotoAlbum.commands.ResizeElementCommand')
+    @patch("pyPhotoAlbum.commands.ResizeElementCommand")
     def test_resize_with_only_size_change(self, mock_cmd_class, qtbot):
         """Test resize command when only size changes (position same)"""
         widget = TestUndoableWidget()
@@ -479,7 +471,7 @@ class TestInteractionEdgeCases:
         assert mock_cmd_class.called
         assert mock_window.project.history.execute.called
 
-    @patch('pyPhotoAlbum.commands.ResizeElementCommand')
+    @patch("pyPhotoAlbum.commands.ResizeElementCommand")
     def test_resize_with_only_position_change(self, mock_cmd_class, qtbot):
         """Test resize command when only position changes (size same)"""
         widget = TestUndoableWidget()
diff --git a/tests/test_interaction_undo_refactored.py b/tests/test_interaction_undo_refactored.py
index c9496db..a39417a 100644
--- a/tests/test_interaction_undo_refactored.py
+++ b/tests/test_interaction_undo_refactored.py
@@ -31,8 +31,8 @@ class TestUndoableInteractionMixinRefactored:
         """Test that mixin initializes correctly."""
         widget = MockWidget()
 
-        assert hasattr(widget, '_command_factory')
-        assert hasattr(widget, '_interaction_state')
+        assert hasattr(widget, "_command_factory")
+        assert hasattr(widget, "_interaction_state")
 
     def test_begin_move(self):
         """Test beginning a move interaction."""
@@ -43,7 +43,7 @@ class TestUndoableInteractionMixinRefactored:
         widget._begin_move(element)
 
         assert widget._interaction_state.element == element
-        assert widget._interaction_state.interaction_type == 'move'
+        assert widget._interaction_state.interaction_type == "move"
         assert widget._interaction_state.position == (0.0, 0.0)
 
     def test_begin_resize(self):
@@ -56,7 +56,7 @@ class TestUndoableInteractionMixinRefactored:
         widget._begin_resize(element)
 
         assert widget._interaction_state.element == element
-        assert widget._interaction_state.interaction_type == 'resize'
+        assert widget._interaction_state.interaction_type == "resize"
         assert widget._interaction_state.position == (0.0, 0.0)
         assert widget._interaction_state.size == (100.0, 100.0)
 
@@ -69,7 +69,7 @@ class TestUndoableInteractionMixinRefactored:
         widget._begin_rotate(element)
 
         assert widget._interaction_state.element == element
-        assert widget._interaction_state.interaction_type == 'rotate'
+        assert widget._interaction_state.interaction_type == "rotate"
         assert widget._interaction_state.rotation == 0.0
 
     def test_begin_image_pan(self):
@@ -83,7 +83,7 @@ class TestUndoableInteractionMixinRefactored:
         widget._begin_image_pan(element)
 
         assert widget._interaction_state.element == element
-        assert widget._interaction_state.interaction_type == 'image_pan'
+        assert widget._interaction_state.interaction_type == "image_pan"
         assert widget._interaction_state.crop_info == (0.0, 0.0, 1.0, 1.0)
 
     def test_begin_image_pan_non_image_element(self):
@@ -211,7 +211,7 @@ class TestUndoableInteractionMixinRefactored:
         """Test that ending interaction without project is safe."""
         widget = MockWidget()
         # Remove the project attribute entirely
-        delattr(widget._mock_window, 'project')
+        delattr(widget._mock_window, "project")
 
         element = Mock(spec=BaseLayoutElement)
         element.position = (0.0, 0.0)
diff --git a/tests/test_interaction_validators.py b/tests/test_interaction_validators.py
index 733bc7c..5c8fa85 100644
--- a/tests/test_interaction_validators.py
+++ b/tests/test_interaction_validators.py
@@ -3,10 +3,7 @@ Unit tests for interaction validators and change detection.
 """
 
 import pytest
-from pyPhotoAlbum.mixins.interaction_validators import (
-    ChangeValidator,
-    InteractionChangeDetector
-)
+from pyPhotoAlbum.mixins.interaction_validators import ChangeValidator, InteractionChangeDetector
 
 
 class TestChangeValidator:
@@ -104,10 +101,10 @@ class TestInteractionChangeDetector:
         change = detector.detect_position_change(old_pos, new_pos)
 
         assert change is not None
-        assert change['old_position'] == old_pos
-        assert change['new_position'] == new_pos
-        assert change['delta_x'] == 5.0
-        assert change['delta_y'] == 3.0
+        assert change["old_position"] == old_pos
+        assert change["new_position"] == new_pos
+        assert change["delta_x"] == 5.0
+        assert change["delta_y"] == 3.0
 
     def test_detect_position_change_insignificant(self):
         """Test that insignificant position changes return None."""
@@ -128,10 +125,10 @@ class TestInteractionChangeDetector:
         change = detector.detect_size_change(old_size, new_size)
 
         assert change is not None
-        assert change['old_size'] == old_size
-        assert change['new_size'] == new_size
-        assert change['delta_width'] == 50.0
-        assert change['delta_height'] == 20.0
+        assert change["old_size"] == old_size
+        assert change["new_size"] == new_size
+        assert change["delta_width"] == 50.0
+        assert change["delta_height"] == 20.0
 
     def test_detect_rotation_change_significant(self):
         """Test detecting significant rotation changes."""
@@ -142,9 +139,9 @@ class TestInteractionChangeDetector:
         change = detector.detect_rotation_change(old_rotation, new_rotation)
 
         assert change is not None
-        assert change['old_rotation'] == old_rotation
-        assert change['new_rotation'] == new_rotation
-        assert change['delta_angle'] == 45.0
+        assert change["old_rotation"] == old_rotation
+        assert change["new_rotation"] == new_rotation
+        assert change["delta_angle"] == 45.0
 
     def test_detect_crop_change_significant(self):
         """Test detecting significant crop changes."""
@@ -155,13 +152,13 @@ class TestInteractionChangeDetector:
         change = detector.detect_crop_change(old_crop, new_crop)
 
         assert change is not None
-        assert change['old_crop'] == old_crop
-        assert change['new_crop'] == new_crop
+        assert change["old_crop"] == old_crop
+        assert change["new_crop"] == new_crop
         # Use approximate comparison for floating point
-        assert abs(change['delta'][0] - 0.1) < 0.001
-        assert abs(change['delta'][1] - 0.1) < 0.001
-        assert abs(change['delta'][2] - (-0.1)) < 0.001
-        assert abs(change['delta'][3] - (-0.1)) < 0.001
+        assert abs(change["delta"][0] - 0.1) < 0.001
+        assert abs(change["delta"][1] - 0.1) < 0.001
+        assert abs(change["delta"][2] - (-0.1)) < 0.001
+        assert abs(change["delta"][3] - (-0.1)) < 0.001
 
     def test_custom_threshold(self):
         """Test using custom threshold values."""
diff --git a/tests/test_merge.py b/tests/test_merge.py
index 0f4a2c0..99cdedf 100755
--- a/tests/test_merge.py
+++ b/tests/test_merge.py
@@ -26,10 +26,7 @@ def create_base_project():
 
     # Add a page with text
     page = Page(page_number=1)
-    text = TextBoxData(
-        text_content="Original Text",
-        x=10, y=10, width=100, height=50
-    )
+    text = TextBoxData(text_content="Original Text", x=10, y=10, width=100, height=50)
     page.layout.add_element(text)
     project.add_page(page)
 
@@ -145,7 +142,7 @@ def test_different_project_concatenation():
         print("\n3. Concatenating projects...")
         merged_data = concatenate_projects(data_a, data_b)
 
-        assert len(merged_data['pages']) == 2, "Should have 2 pages"
+        assert len(merged_data["pages"]) == 2, "Should have 2 pages"
         print(f"   ✓ Concatenated project has {len(merged_data['pages'])} pages")
         print(f"   ✓ Combined name: {merged_data['name']}")
 
@@ -252,6 +249,7 @@ def run_all_tests():
         except Exception as e:
             print(f"\n❌ Test '{name}' FAILED with exception: {e}")
             import traceback
+
             traceback.print_exc()
             results.append((name, False))
 
@@ -293,20 +291,20 @@ def test_merge_helper_add_missing_pages():
     data_b = project_b.serialize()
 
     # Make them same project
-    data_b['project_id'] = data_a['project_id']
+    data_b["project_id"] = data_a["project_id"]
 
     merge_manager = MergeManager()
     merge_manager.detect_conflicts(data_a, data_b)
 
     # Test _add_missing_pages
     merged_data = data_a.copy()
-    merged_data['pages'] = list(data_a['pages'])
-    initial_page_count = len(merged_data['pages'])
+    merged_data["pages"] = list(data_a["pages"])
+    initial_page_count = len(merged_data["pages"])
 
     merge_manager._add_missing_pages(merged_data, data_b)
 
     # Should have added only page_b2 since page_b1 has same UUID as page_a1
-    assert len(merged_data['pages']) == initial_page_count + 1
+    assert len(merged_data["pages"]) == initial_page_count + 1
     print(f"   ✓ Added missing page: {len(merged_data['pages'])} total pages")
 
     print(f"\n{'=' * 60}")
@@ -332,7 +330,7 @@ def test_merge_helper_is_element_in_conflict():
         element_uuid="elem-456",
         our_version={},
         their_version={},
-        description="Test conflict"
+        description="Test conflict",
     )
     merge_manager.conflicts.append(conflict)
 
@@ -365,50 +363,24 @@ def test_merge_helper_merge_by_timestamp():
     older = (now - timedelta(hours=1)).isoformat()
     newer = (now + timedelta(hours=1)).isoformat()
 
-    our_page = {
-        'layout': {
-            'elements': [
-                {
-                    'uuid': 'elem-1',
-                    'text_content': 'Older version',
-                    'last_modified': older
-                }
-            ]
-        }
-    }
+    our_page = {"layout": {"elements": [{"uuid": "elem-1", "text_content": "Older version", "last_modified": older}]}}
 
-    our_elem = our_page['layout']['elements'][0]
-    their_elem = {
-        'uuid': 'elem-1',
-        'text_content': 'Newer version',
-        'last_modified': newer
-    }
+    our_elem = our_page["layout"]["elements"][0]
+    their_elem = {"uuid": "elem-1", "text_content": "Newer version", "last_modified": newer}
 
     # Test: their version is newer, should replace
-    merge_manager._merge_by_timestamp(our_page, 'elem-1', their_elem, our_elem)
+    merge_manager._merge_by_timestamp(our_page, "elem-1", their_elem, our_elem)
 
-    assert our_page['layout']['elements'][0]['text_content'] == 'Newer version'
+    assert our_page["layout"]["elements"][0]["text_content"] == "Newer version"
     print(f"   ✓ Correctly replaced with newer version")
 
     # Test: our version is newer, should not replace
-    our_page['layout']['elements'][0] = {
-        'uuid': 'elem-2',
-        'text_content': 'Our newer version',
-        'last_modified': newer
-    }
-    their_elem_older = {
-        'uuid': 'elem-2',
-        'text_content': 'Their older version',
-        'last_modified': older
-    }
+    our_page["layout"]["elements"][0] = {"uuid": "elem-2", "text_content": "Our newer version", "last_modified": newer}
+    their_elem_older = {"uuid": "elem-2", "text_content": "Their older version", "last_modified": older}
 
-    merge_manager._merge_by_timestamp(
-        our_page, 'elem-2',
-        their_elem_older,
-        our_page['layout']['elements'][0]
-    )
+    merge_manager._merge_by_timestamp(our_page, "elem-2", their_elem_older, our_page["layout"]["elements"][0])
 
-    assert our_page['layout']['elements'][0]['text_content'] == 'Our newer version'
+    assert our_page["layout"]["elements"][0]["text_content"] == "Our newer version"
     print(f"   ✓ Correctly kept our newer version")
 
     print(f"\n{'=' * 60}")
@@ -430,73 +402,49 @@ def test_merge_helper_merge_element():
 
     # Setup: page with one element
     our_page = {
-        'uuid': 'page-1',
-        'layout': {
-            'elements': [
-                {
-                    'uuid': 'elem-existing',
-                    'text_content': 'Existing',
-                    'last_modified': now
-                }
-            ]
-        }
+        "uuid": "page-1",
+        "layout": {"elements": [{"uuid": "elem-existing", "text_content": "Existing", "last_modified": now}]},
     }
 
-    our_elements = {
-        'elem-existing': our_page['layout']['elements'][0]
-    }
+    our_elements = {"elem-existing": our_page["layout"]["elements"][0]}
 
     # Test 1: Adding new element
-    their_new_elem = {
-        'uuid': 'elem-new',
-        'text_content': 'New element',
-        'last_modified': now
-    }
+    their_new_elem = {"uuid": "elem-new", "text_content": "New element", "last_modified": now}
 
     merge_manager._merge_element(
-        our_page=our_page,
-        page_uuid='page-1',
-        their_elem=their_new_elem,
-        our_elements=our_elements
+        our_page=our_page, page_uuid="page-1", their_elem=their_new_elem, our_elements=our_elements
     )
 
-    assert len(our_page['layout']['elements']) == 2
-    assert our_page['layout']['elements'][1]['uuid'] == 'elem-new'
+    assert len(our_page["layout"]["elements"]) == 2
+    assert our_page["layout"]["elements"][1]["uuid"] == "elem-new"
     print(f"   ✓ Correctly added new element")
 
     # Test 2: Element in conflict should be skipped
     from pyPhotoAlbum.merge_manager import ConflictInfo, ConflictType
 
-    conflict_elem = {
-        'uuid': 'elem-conflict',
-        'text_content': 'Conflict element',
-        'last_modified': now
-    }
+    conflict_elem = {"uuid": "elem-conflict", "text_content": "Conflict element", "last_modified": now}
 
     conflict = ConflictInfo(
         conflict_type=ConflictType.ELEMENT_MODIFIED_BOTH,
-        page_uuid='page-1',
-        element_uuid='elem-conflict',
+        page_uuid="page-1",
+        element_uuid="elem-conflict",
         our_version={},
         their_version={},
-        description="Test"
+        description="Test",
     )
     merge_manager.conflicts.append(conflict)
 
-    our_elements['elem-conflict'] = {'uuid': 'elem-conflict', 'text_content': 'Ours'}
-    our_page['layout']['elements'].append(our_elements['elem-conflict'])
+    our_elements["elem-conflict"] = {"uuid": "elem-conflict", "text_content": "Ours"}
+    our_page["layout"]["elements"].append(our_elements["elem-conflict"])
 
-    initial_count = len(our_page['layout']['elements'])
+    initial_count = len(our_page["layout"]["elements"])
 
     merge_manager._merge_element(
-        our_page=our_page,
-        page_uuid='page-1',
-        their_elem=conflict_elem,
-        our_elements=our_elements
+        our_page=our_page, page_uuid="page-1", their_elem=conflict_elem, our_elements=our_elements
     )
 
     # Should not change anything since it's in conflict
-    assert len(our_page['layout']['elements']) == initial_count
+    assert len(our_page["layout"]["elements"]) == initial_count
     print(f"   ✓ Correctly skipped conflicting element")
 
     print(f"\n{'=' * 60}")
diff --git a/tests/test_migration.py b/tests/test_migration.py
index b771c6a..bc0c8c0 100755
--- a/tests/test_migration.py
+++ b/tests/test_migration.py
@@ -49,29 +49,16 @@ def create_v2_project_json():
                             "rotation": 0,
                             "z_index": 0,
                             "text_content": "Hello v2.0",
-                            "font_settings": {
-                                "family": "Arial",
-                                "size": 12,
-                                "color": [0, 0, 0]
-                            },
-                            "alignment": "left"
+                            "font_settings": {"family": "Arial", "size": 12, "color": [0, 0, 0]},
+                            "alignment": "left",
                         }
                     ],
-                    "snapping_system": {
-                        "snap_threshold_mm": 5.0,
-                        "grid_size_mm": 10.0
-                    }
-                }
+                    "snapping_system": {"snap_threshold_mm": 5.0, "grid_size_mm": 10.0},
+                },
             }
         ],
-        "history": {
-            "undo_stack": [],
-            "redo_stack": [],
-            "max_history": 100
-        },
-        "asset_manager": {
-            "reference_counts": {}
-        }
+        "history": {"undo_stack": [], "redo_stack": [], "max_history": 100},
+        "asset_manager": {"reference_counts": {}},
     }
 
 
@@ -88,9 +75,9 @@ def test_migration():
         print(f"\n1. Creating v2.0 project file: {v2_file}")
         v2_data = create_v2_project_json()
 
-        with zipfile.ZipFile(v2_file, 'w', zipfile.ZIP_DEFLATED) as zipf:
+        with zipfile.ZipFile(v2_file, "w", zipfile.ZIP_DEFLATED) as zipf:
             project_json = json.dumps(v2_data, indent=2)
-            zipf.writestr('project.json', project_json)
+            zipf.writestr("project.json", project_json)
 
         print(f"   ✓ Created v2.0 project with {len(v2_data['pages'])} page(s)")
         print(f"   ✓ Version: {v2_data['data_version']}")
@@ -107,9 +94,9 @@ def test_migration():
             print(f"\n3. Verifying migration to v3.0...")
 
             # Check project-level fields
-            assert hasattr(project, 'project_id'), "Missing project_id"
-            assert hasattr(project, 'created'), "Missing created timestamp"
-            assert hasattr(project, 'last_modified'), "Missing last_modified timestamp"
+            assert hasattr(project, "project_id"), "Missing project_id"
+            assert hasattr(project, "created"), "Missing created timestamp"
+            assert hasattr(project, "last_modified"), "Missing last_modified timestamp"
             print(f"   ✓ Project has project_id: {project.project_id}")
             print(f"   ✓ Project has created: {project.created}")
             print(f"   ✓ Project has last_modified: {project.last_modified}")
@@ -117,20 +104,20 @@ def test_migration():
             # Check page-level fields
             assert len(project.pages) > 0, "No pages in project"
             page = project.pages[0]
-            assert hasattr(page, 'uuid'), "Page missing uuid"
-            assert hasattr(page, 'created'), "Page missing created"
-            assert hasattr(page, 'last_modified'), "Page missing last_modified"
-            assert hasattr(page, 'deleted'), "Page missing deleted flag"
+            assert hasattr(page, "uuid"), "Page missing uuid"
+            assert hasattr(page, "created"), "Page missing created"
+            assert hasattr(page, "last_modified"), "Page missing last_modified"
+            assert hasattr(page, "deleted"), "Page missing deleted flag"
             print(f"   ✓ Page 1 has uuid: {page.uuid}")
             print(f"   ✓ Page 1 has timestamps and deletion tracking")
 
             # Check element-level fields
             assert len(page.layout.elements) > 0, "No elements in page"
             element = page.layout.elements[0]
-            assert hasattr(element, 'uuid'), "Element missing uuid"
-            assert hasattr(element, 'created'), "Element missing created"
-            assert hasattr(element, 'last_modified'), "Element missing last_modified"
-            assert hasattr(element, 'deleted'), "Element missing deleted flag"
+            assert hasattr(element, "uuid"), "Element missing uuid"
+            assert hasattr(element, "created"), "Element missing created"
+            assert hasattr(element, "last_modified"), "Element missing last_modified"
+            assert hasattr(element, "deleted"), "Element missing deleted flag"
             print(f"   ✓ Element has uuid: {element.uuid}")
             print(f"   ✓ Element has timestamps and deletion tracking")
 
@@ -142,14 +129,14 @@ def test_migration():
             print(f"   ✓ Saved to: {v3_file}")
 
             # Verify v3.0 file structure
-            with zipfile.ZipFile(v3_file, 'r') as zipf:
-                project_json = zipf.read('project.json').decode('utf-8')
+            with zipfile.ZipFile(v3_file, "r") as zipf:
+                project_json = zipf.read("project.json").decode("utf-8")
                 v3_data = json.loads(project_json)
 
-                assert v3_data.get('data_version') == "3.0", "Wrong version"
-                assert 'project_id' in v3_data, "Missing project_id in saved file"
-                assert 'created' in v3_data, "Missing created in saved file"
-                assert 'uuid' in v3_data['pages'][0], "Missing page uuid in saved file"
+                assert v3_data.get("data_version") == "3.0", "Wrong version"
+                assert "project_id" in v3_data, "Missing project_id in saved file"
+                assert "created" in v3_data, "Missing created in saved file"
+                assert "uuid" in v3_data["pages"][0], "Missing page uuid in saved file"
 
                 print(f"   ✓ Saved file version: {v3_data.get('data_version')}")
                 print(f"   ✓ All v3.0 fields present in saved file")
@@ -164,6 +151,7 @@ def test_migration():
             print(f"❌ Migration test FAILED: {e}")
             print(f"{'=' * 60}\n")
             import traceback
+
             traceback.print_exc()
             return False
 
diff --git a/tests/test_models.py b/tests/test_models.py
index 8f878b0..264a02e 100755
--- a/tests/test_models.py
+++ b/tests/test_models.py
@@ -30,15 +30,7 @@ class TestImageData:
 
     def test_initialization_with_parameters(self, temp_image_file):
         """Test ImageData initialization with custom parameters"""
-        img = ImageData(
-            image_path=temp_image_file,
-            x=10.0,
-            y=20.0,
-            width=200.0,
-            height=150.0,
-            rotation=45.0,
-            z_index=5
-        )
+        img = ImageData(image_path=temp_image_file, x=10.0, y=20.0, width=200.0, height=150.0, rotation=45.0, z_index=5)
         assert img.image_path == temp_image_file
         assert img.position == (10.0, 20.0)
         assert img.size == (200.0, 150.0)
@@ -53,15 +45,7 @@ class TestImageData:
 
     def test_serialization(self, temp_image_file):
         """Test ImageData serialization to dictionary"""
-        img = ImageData(
-            image_path=temp_image_file,
-            x=15.0,
-            y=25.0,
-            width=180.0,
-            height=120.0,
-            rotation=30.0,
-            z_index=3
-        )
+        img = ImageData(image_path=temp_image_file, x=15.0, y=25.0, width=180.0, height=120.0, rotation=30.0, z_index=3)
         data = img.serialize()
 
         assert data["type"] == "image"
@@ -81,7 +65,7 @@ class TestImageData:
             "rotation": 90.0,
             "z_index": 7,
             "image_path": "new_image.jpg",
-            "crop_info": (0.2, 0.3, 0.7, 0.8)
+            "crop_info": (0.2, 0.3, 0.7, 0.8),
         }
         img.deserialize(data)
 
@@ -118,7 +102,7 @@ class TestImageData:
             height=200.0,
             rotation=0,  # Visual rotation should be 0 for images
             z_index=2,
-            crop_info=(0.1, 0.1, 0.9, 0.9)
+            crop_info=(0.1, 0.1, 0.9, 0.9),
         )
         original.pil_rotation_90 = 1  # Set PIL rotation to 90 degrees
 
@@ -170,7 +154,7 @@ class TestPlaceholderData:
             width=150.0,
             height=100.0,
             rotation=10.0,
-            z_index=4
+            z_index=4,
         )
         assert placeholder.placeholder_type == "text"
         assert placeholder.default_content == "Sample"
@@ -189,7 +173,7 @@ class TestPlaceholderData:
             width=200.0,
             height=150.0,
             rotation=20.0,
-            z_index=2
+            z_index=2,
         )
         data = placeholder.serialize()
 
@@ -210,7 +194,7 @@ class TestPlaceholderData:
             "rotation": 45.0,
             "z_index": 6,
             "placeholder_type": "text",
-            "default_content": "Default Text"
+            "default_content": "Default Text",
         }
         placeholder.deserialize(data)
 
@@ -243,7 +227,7 @@ class TestPlaceholderData:
             width=300.0,
             height=250.0,
             rotation=60.0,
-            z_index=8
+            z_index=8,
         )
         data = original.serialize()
         restored = PlaceholderData()
@@ -283,7 +267,7 @@ class TestTextBoxData:
             width=180.0,
             height=60.0,
             rotation=5.0,
-            z_index=3
+            z_index=3,
         )
         assert textbox.text_content == "Hello World"
         assert textbox.font_settings == font_settings
@@ -305,7 +289,7 @@ class TestTextBoxData:
             width=220.0,
             height=80.0,
             rotation=15.0,
-            z_index=5
+            z_index=5,
         )
         data = textbox.serialize()
 
@@ -329,7 +313,7 @@ class TestTextBoxData:
             "z_index": 7,
             "text_content": "Deserialized Text",
             "font_settings": font_settings,
-            "alignment": "justify"
+            "alignment": "justify",
         }
         textbox.deserialize(data)
 
@@ -366,7 +350,7 @@ class TestTextBoxData:
             width=320.0,
             height=120.0,
             rotation=25.0,
-            z_index=9
+            z_index=9,
         )
         data = original.serialize()
         restored = TextBoxData()
diff --git a/tests/test_mouse_interaction_mixin.py b/tests/test_mouse_interaction_mixin.py
index dcea02a..de57774 100755
--- a/tests/test_mouse_interaction_mixin.py
+++ b/tests/test_mouse_interaction_mixin.py
@@ -28,7 +28,7 @@ class TestMouseInteractionWidget(
     ElementSelectionMixin,
     ViewportMixin,
     UndoableInteractionMixin,
-    QOpenGLWidget
+    QOpenGLWidget,
 ):
     """Test widget combining mouse interaction with other required mixins"""
 
@@ -49,9 +49,9 @@ class TestMouseInteractionInitialization:
         qtbot.addWidget(widget)
 
         # Should have initialized state
-        assert hasattr(widget, 'drag_start_pos')
-        assert hasattr(widget, 'is_dragging')
-        assert hasattr(widget, 'is_panning')
+        assert hasattr(widget, "drag_start_pos")
+        assert hasattr(widget, "is_dragging")
+        assert hasattr(widget, "is_panning")
         assert widget.drag_start_pos is None
         assert widget.is_dragging is False
         assert widget.is_panning is False
@@ -123,8 +123,11 @@ class TestMousePressEvent:
         # Create image element with crop info
         element = ImageData(
             image_path="/test.jpg",
-            x=50, y=50, width=100, height=100,
-            crop_info=(0.0, 0.0, 1.0, 1.0)  # crop_info is a tuple (x, y, width, height)
+            x=50,
+            y=50,
+            width=100,
+            height=100,
+            crop_info=(0.0, 0.0, 1.0, 1.0),  # crop_info is a tuple (x, y, width, height)
         )
 
         event = Mock()
@@ -205,7 +208,7 @@ class TestMouseMoveEvent:
         event.buttons = Mock(return_value=Qt.MouseButton.NoButton)
 
         # Mock resize handle detection
-        widget._get_resize_handle_at = Mock(return_value='bottom-right')
+        widget._get_resize_handle_at = Mock(return_value="bottom-right")
         widget._get_element_at = Mock(return_value=element)
 
         widget.mouseMoveEvent(event)
@@ -295,9 +298,11 @@ class TestMouseMoveEvent:
         # Create image element with crop info
         element = ImageData(
             image_path="/test.jpg",
-            x=100, y=100,
-            width=100, height=100,
-            crop_info=(0.0, 0.0, 1.0, 1.0)  # crop_info is a tuple (x, y, width, height)
+            x=100,
+            y=100,
+            width=100,
+            height=100,
+            crop_info=(0.0, 0.0, 1.0, 1.0),  # crop_info is a tuple (x, y, width, height)
         )
         widget.selected_elements.add(element)
 
@@ -377,9 +382,11 @@ class TestMouseDoubleClickEvent:
         # Create text element with correct constructor
         text_element = TextBoxData(
             text_content="Test",
-            x=100, y=100,
-            width=100, height=50,
-            font_settings={"family": "Arial", "size": 12, "color": (0, 0, 0)}
+            x=100,
+            y=100,
+            width=100,
+            height=50,
+            font_settings={"family": "Arial", "size": 12, "color": (0, 0, 0)},
         )
 
         # Mock _edit_text_element method
@@ -394,7 +401,7 @@ class TestMouseDoubleClickEvent:
             QPointF(125, 125),
             Qt.MouseButton.LeftButton,
             Qt.MouseButton.LeftButton,
-            Qt.KeyboardModifier.NoModifier
+            Qt.KeyboardModifier.NoModifier,
         )
 
         widget.mouseDoubleClickEvent(event)
@@ -419,7 +426,7 @@ class TestMouseDoubleClickEvent:
             QPointF(125, 125),
             Qt.MouseButton.LeftButton,
             Qt.MouseButton.LeftButton,
-            Qt.KeyboardModifier.NoModifier
+            Qt.KeyboardModifier.NoModifier,
         )
 
         widget.mouseDoubleClickEvent(event)
diff --git a/tests/test_multiselect.py b/tests/test_multiselect.py
index f24b7be..df92d26 100755
--- a/tests/test_multiselect.py
+++ b/tests/test_multiselect.py
@@ -16,6 +16,7 @@ from pyPhotoAlbum.page_layout import PageLayout
 # Create a minimal test widget class that doesn't require full GLWidget initialization
 class MultiSelectTestWidget(ElementSelectionMixin, RenderingMixin, QOpenGLWidget):
     """Widget combining necessary mixins for multiselect testing"""
+
     def __init__(self):
         super().__init__()
         self._page_renderers = []
@@ -69,7 +70,7 @@ def test_multiselect_visual_feedback(qtbot):
     print("\nTest 1: Single selection")
     widget.selected_elements = {element1}
 
-    with patch.object(widget, '_draw_selection_handles') as mock_draw:
+    with patch.object(widget, "_draw_selection_handles") as mock_draw:
         # Simulate paintGL call (only the relevant part)
         for selected_elem in widget.selected_elements:
             widget._draw_selection_handles(selected_elem)
@@ -82,7 +83,7 @@ def test_multiselect_visual_feedback(qtbot):
     print("\nTest 2: Multiple selection (2 elements)")
     widget.selected_elements = {element1, element2}
 
-    with patch.object(widget, '_draw_selection_handles') as mock_draw:
+    with patch.object(widget, "_draw_selection_handles") as mock_draw:
         for selected_elem in widget.selected_elements:
             widget._draw_selection_handles(selected_elem)
 
@@ -95,7 +96,7 @@ def test_multiselect_visual_feedback(qtbot):
     print("\nTest 3: Multiple selection (3 elements)")
     widget.selected_elements = {element1, element2, element3}
 
-    with patch.object(widget, '_draw_selection_handles') as mock_draw:
+    with patch.object(widget, "_draw_selection_handles") as mock_draw:
         for selected_elem in widget.selected_elements:
             widget._draw_selection_handles(selected_elem)
 
@@ -108,7 +109,7 @@ def test_multiselect_visual_feedback(qtbot):
     print("\nTest 4: No selection")
     widget.selected_elements = set()
 
-    with patch.object(widget, '_draw_selection_handles') as mock_draw:
+    with patch.object(widget, "_draw_selection_handles") as mock_draw:
         for selected_elem in widget.selected_elements:
             widget._draw_selection_handles(selected_elem)
 
@@ -120,15 +121,17 @@ def test_multiselect_visual_feedback(qtbot):
     widget.selected_elements = {element2}
 
     # Mock OpenGL functions
-    with patch('pyPhotoAlbum.gl_widget.glColor3f'), \
-         patch('pyPhotoAlbum.gl_widget.glLineWidth'), \
-         patch('pyPhotoAlbum.gl_widget.glBegin'), \
-         patch('pyPhotoAlbum.gl_widget.glEnd'), \
-         patch('pyPhotoAlbum.gl_widget.glVertex2f'), \
-         patch('pyPhotoAlbum.gl_widget.glPushMatrix'), \
-         patch('pyPhotoAlbum.gl_widget.glPopMatrix'), \
-         patch('pyPhotoAlbum.gl_widget.glTranslatef'), \
-         patch('pyPhotoAlbum.gl_widget.glRotatef'):
+    with (
+        patch("pyPhotoAlbum.gl_widget.glColor3f"),
+        patch("pyPhotoAlbum.gl_widget.glLineWidth"),
+        patch("pyPhotoAlbum.gl_widget.glBegin"),
+        patch("pyPhotoAlbum.gl_widget.glEnd"),
+        patch("pyPhotoAlbum.gl_widget.glVertex2f"),
+        patch("pyPhotoAlbum.gl_widget.glPushMatrix"),
+        patch("pyPhotoAlbum.gl_widget.glPopMatrix"),
+        patch("pyPhotoAlbum.gl_widget.glTranslatef"),
+        patch("pyPhotoAlbum.gl_widget.glRotatef"),
+    ):
 
         # Call the actual method
         widget._draw_selection_handles(element2)
diff --git a/tests/test_page_layout.py b/tests/test_page_layout.py
index bb58027..8283024 100755
--- a/tests/test_page_layout.py
+++ b/tests/test_page_layout.py
@@ -174,7 +174,7 @@ class TestPageLayoutDeserialization:
             "elements": [],
             "grid_layout": None,
             "snapping_system": {},
-            "show_snap_lines": False
+            "show_snap_lines": False,
         }
 
         layout.deserialize(data)
@@ -198,7 +198,7 @@ class TestPageLayoutDeserialization:
                     "size": (100, 100),
                     "rotation": 0,
                     "z_index": 0,
-                    "crop_info": (0, 0, 1, 1)
+                    "crop_info": (0, 0, 1, 1),
                 },
                 {
                     "type": "placeholder",
@@ -207,7 +207,7 @@ class TestPageLayoutDeserialization:
                     "position": (30, 40),
                     "size": (80, 80),
                     "rotation": 0,
-                    "z_index": 1
+                    "z_index": 1,
                 },
                 {
                     "type": "textbox",
@@ -217,9 +217,9 @@ class TestPageLayoutDeserialization:
                     "position": (50, 60),
                     "size": (120, 40),
                     "rotation": 0,
-                    "z_index": 2
-                }
-            ]
+                    "z_index": 2,
+                },
+            ],
         }
 
         layout.deserialize(data)
@@ -242,7 +242,7 @@ class TestPageLayoutDeserialization:
                     "size": (100, 100),
                     "rotation": 0,
                     "z_index": 5,  # Higher z_index
-                    "crop_info": (0, 0, 1, 1)
+                    "crop_info": (0, 0, 1, 1),
                 },
                 {
                     "type": "placeholder",
@@ -251,9 +251,9 @@ class TestPageLayoutDeserialization:
                     "position": (30, 40),
                     "size": (80, 80),
                     "rotation": 0,
-                    "z_index": 1  # Lower z_index - should be first
-                }
-            ]
+                    "z_index": 1,  # Lower z_index - should be first
+                },
+            ],
         }
 
         layout.deserialize(data)
@@ -269,12 +269,7 @@ class TestPageLayoutDeserialization:
         data = {
             "size": (210, 297),
             "elements": [],
-            "grid_layout": {
-                "rows": 2,
-                "columns": 3,
-                "spacing": 12.5,
-                "merged_cells": [(0, 0), (1, 1)]
-            }
+            "grid_layout": {"rows": 2, "columns": 3, "spacing": 12.5, "merged_cells": [(0, 0), (1, 1)]},
         }
 
         layout.deserialize(data)
@@ -291,10 +286,7 @@ class TestPageLayoutDeserialization:
         data = {
             "size": (210, 297),
             "elements": [
-                {
-                    "type": "unknown_type",
-                    "position": (10, 20)
-                },
+                {"type": "unknown_type", "position": (10, 20)},
                 {
                     "type": "image",
                     "image_path": "test.jpg",
@@ -302,9 +294,9 @@ class TestPageLayoutDeserialization:
                     "size": (100, 100),
                     "rotation": 0,
                     "z_index": 0,
-                    "crop_info": (0, 0, 1, 1)
-                }
-            ]
+                    "crop_info": (0, 0, 1, 1),
+                },
+            ],
         }
 
         layout.deserialize(data)
@@ -430,12 +422,7 @@ class TestGridLayoutClass:
     def test_grid_deserialization(self):
         """Test GridLayout deserialization"""
         grid = GridLayout()
-        data = {
-            "rows": 4,
-            "columns": 5,
-            "spacing": 8.5,
-            "merged_cells": [(1, 2), (3, 3)]
-        }
+        data = {"rows": 4, "columns": 5, "spacing": 8.5, "merged_cells": [(1, 2), (3, 3)]}
 
         grid.deserialize(data)
 
diff --git a/tests/test_page_navigation_mixin.py b/tests/test_page_navigation_mixin.py
index 3314ef7..c4ad904 100755
--- a/tests/test_page_navigation_mixin.py
+++ b/tests/test_page_navigation_mixin.py
@@ -15,6 +15,7 @@ from pyPhotoAlbum.models import GhostPageData
 # Create test widget combining necessary mixins
 class TestPageNavWidget(PageNavigationMixin, ViewportMixin, QOpenGLWidget):
     """Test widget combining page navigation and viewport mixins"""
+
     pass
 
 
@@ -149,9 +150,7 @@ class TestGetPagePositions:
         mock_window.project.pages = [page]
 
         # Mock calculate_page_layout_with_ghosts
-        mock_window.project.calculate_page_layout_with_ghosts = Mock(return_value=[
-            ('page', page, 0)
-        ])
+        mock_window.project.calculate_page_layout_with_ghosts = Mock(return_value=[("page", page, 0)])
 
         widget.window = Mock(return_value=mock_window)
 
@@ -159,7 +158,7 @@ class TestGetPagePositions:
 
         # Should have one page entry
         assert len(result) >= 1
-        assert result[0][0] == 'page'
+        assert result[0][0] == "page"
         assert result[0][1] is page
 
     def test_get_page_positions_includes_ghosts(self, qtbot):
@@ -177,10 +176,9 @@ class TestGetPagePositions:
         mock_window.project.pages = [page]
 
         # Mock with ghost page
-        mock_window.project.calculate_page_layout_with_ghosts = Mock(return_value=[
-            ('page', page, 0),
-            ('ghost', None, 1)
-        ])
+        mock_window.project.calculate_page_layout_with_ghosts = Mock(
+            return_value=[("page", page, 0), ("ghost", None, 1)]
+        )
 
         widget.window = Mock(return_value=mock_window)
 
@@ -189,8 +187,8 @@ class TestGetPagePositions:
         # Should have page + ghost
         assert len(result) >= 2
         page_types = [r[0] for r in result]
-        assert 'page' in page_types
-        assert 'ghost' in page_types
+        assert "page" in page_types
+        assert "ghost" in page_types
 
 
 class TestCheckGhostPageClick:
@@ -217,7 +215,7 @@ class TestCheckGhostPageClick:
         result = widget._check_ghost_page_click(100, 100)
         assert result is False
 
-    @patch('pyPhotoAlbum.page_renderer.PageRenderer')
+    @patch("pyPhotoAlbum.page_renderer.PageRenderer")
     def test_check_ghost_page_click_on_ghost(self, mock_page_renderer_class, qtbot):
         """Test clicking on ghost page creates new page"""
         widget = TestPageNavWidget()
@@ -238,9 +236,7 @@ class TestCheckGhostPageClick:
 
         # Mock _get_page_positions to return a ghost
         ghost = GhostPageData(page_size=(210, 297))
-        widget._get_page_positions = Mock(return_value=[
-            ('ghost', ghost, 100)
-        ])
+        widget._get_page_positions = Mock(return_value=[("ghost", ghost, 100)])
 
         # Mock PageRenderer to say click is in page
         mock_renderer_instance = Mock()
@@ -257,7 +253,7 @@ class TestCheckGhostPageClick:
         assert len(mock_window.project.pages) == 1
         assert widget.update.called
 
-    @patch('pyPhotoAlbum.page_renderer.PageRenderer')
+    @patch("pyPhotoAlbum.page_renderer.PageRenderer")
     def test_check_ghost_page_click_outside_ghost(self, mock_page_renderer_class, qtbot):
         """Test clicking outside ghost page returns False"""
         widget = TestPageNavWidget()
@@ -273,9 +269,7 @@ class TestCheckGhostPageClick:
         mock_window.project.pages = []
 
         ghost = GhostPageData(page_size=(210, 297))
-        widget._get_page_positions = Mock(return_value=[
-            ('ghost', ghost, 100)
-        ])
+        widget._get_page_positions = Mock(return_value=[("ghost", ghost, 100)])
 
         # Mock renderer to say click is NOT in page
         mock_renderer_instance = Mock()
diff --git a/tests/test_page_ops_mixin.py b/tests/test_page_ops_mixin.py
index 46ef0bb..e47331d 100755
--- a/tests/test_page_ops_mixin.py
+++ b/tests/test_page_ops_mixin.py
@@ -98,11 +98,7 @@ class TestGetMostVisiblePageIndex:
         renderer3 = Mock()
         renderer3.screen_y = 800
 
-        window.gl_widget._page_renderers = [
-            (renderer1, page1),
-            (renderer2, page2),
-            (renderer3, page3)
-        ]
+        window.gl_widget._page_renderers = [(renderer1, page1), (renderer2, page2), (renderer3, page3)]
 
         result = window._get_most_visible_page_index()
         # Page 2 (index 1) should be closest to viewport center
@@ -122,10 +118,7 @@ class TestGetMostVisiblePageIndex:
         renderer_orphan = Mock()
         renderer_orphan.screen_y = 50  # Closer to center
 
-        window.gl_widget._page_renderers = [
-            (renderer1, page1),
-            (renderer_orphan, orphan_page)  # Not in project.pages
-        ]
+        window.gl_widget._page_renderers = [(renderer1, page1), (renderer_orphan, orphan_page)]  # Not in project.pages
         window.gl_widget.current_page_index = 0
 
         result = window._get_most_visible_page_index()
@@ -222,11 +215,7 @@ class TestToggleDoubleSpread:
         renderer3 = Mock()
         renderer3.screen_y = 800
 
-        window.gl_widget._page_renderers = [
-            (renderer1, page1),
-            (renderer2, page2),
-            (renderer3, page3)
-        ]
+        window.gl_widget._page_renderers = [(renderer1, page1), (renderer2, page2), (renderer3, page3)]
 
         window.toggle_double_spread()
 
@@ -340,11 +329,7 @@ class TestAddPage:
         renderer3 = Mock()
         renderer3.screen_y = 800
 
-        window.gl_widget._page_renderers = [
-            (renderer1, page1),
-            (renderer2, page2),
-            (renderer3, page3)
-        ]
+        window.gl_widget._page_renderers = [(renderer1, page1), (renderer2, page2), (renderer3, page3)]
 
         window.add_page()
 
@@ -387,11 +372,7 @@ class TestAddPage:
         renderer3 = Mock()
         renderer3.screen_y = 1500
 
-        window.gl_widget._page_renderers = [
-            (renderer1, page1),
-            (renderer2, page2),
-            (renderer3, page3)
-        ]
+        window.gl_widget._page_renderers = [(renderer1, page1), (renderer2, page2), (renderer3, page3)]
 
         window.add_page()
 
@@ -458,11 +439,7 @@ class TestRemovePage:
         renderer3 = Mock()
         renderer3.screen_y = -300  # Page 3 is most visible
 
-        window.gl_widget._page_renderers = [
-            (renderer1, page1),
-            (renderer2, page2),
-            (renderer3, page3)
-        ]
+        window.gl_widget._page_renderers = [(renderer1, page1), (renderer2, page2), (renderer3, page3)]
 
         window.remove_page()
 
diff --git a/tests/test_page_renderer.py b/tests/test_page_renderer.py
index 396737b..02c06fe 100755
--- a/tests/test_page_renderer.py
+++ b/tests/test_page_renderer.py
@@ -8,164 +8,124 @@ from pyPhotoAlbum.page_renderer import PageRenderer
 
 class TestPageRendererCoordinates:
     """Test coordinate transformation methods"""
-    
+
     def test_page_to_screen_no_zoom_no_pan(self):
         """Test page_to_screen conversion with zoom=1.0 and no pan"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=1.0
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=1.0
         )
-        
+
         # Element at page origin should map to screen_x, screen_y
         screen_x, screen_y = renderer.page_to_screen(0, 0)
         assert screen_x == 100.0
         assert screen_y == 200.0
-        
+
         # Element at (50, 75) should be offset by that amount
         screen_x, screen_y = renderer.page_to_screen(50, 75)
         assert screen_x == 150.0
         assert screen_y == 275.0
-    
+
     def test_page_to_screen_with_zoom(self):
         """Test page_to_screen conversion with zoom applied"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=2.0
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=2.0
         )
-        
+
         # With zoom=2.0, distances should be doubled
         screen_x, screen_y = renderer.page_to_screen(50, 75)
         assert screen_x == 200.0  # 100 + 50*2
         assert screen_y == 350.0  # 200 + 75*2
-    
+
     def test_page_to_screen_with_fractional_zoom(self):
         """Test page_to_screen conversion with fractional zoom"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=0.5
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=0.5
         )
-        
+
         # With zoom=0.5, distances should be halved
         screen_x, screen_y = renderer.page_to_screen(100, 150)
         assert screen_x == 150.0  # 100 + 100*0.5
         assert screen_y == 275.0  # 200 + 150*0.5
-    
+
     def test_screen_to_page_no_zoom_no_pan(self):
         """Test screen_to_page conversion with zoom=1.0 and no pan"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=1.0
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=1.0
         )
-        
+
         # Screen position at screen_x, screen_y should map to page origin
         page_x, page_y = renderer.screen_to_page(100.0, 200.0)
         assert page_x == 0.0
         assert page_y == 0.0
-        
+
         # Screen position offset should map to same offset in page coords
         page_x, page_y = renderer.screen_to_page(150.0, 275.0)
         assert page_x == 50.0
         assert page_y == 75.0
-    
+
     def test_screen_to_page_with_zoom(self):
         """Test screen_to_page conversion with zoom applied"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=2.0
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=2.0
         )
-        
+
         # With zoom=2.0, screen distances should be divided by 2 to get page coords
         page_x, page_y = renderer.screen_to_page(200.0, 350.0)
         assert page_x == 50.0  # (200-100)/2
         assert page_y == 75.0  # (350-200)/2
-    
+
     def test_roundtrip_conversion_no_zoom(self):
         """Test that page->screen->page conversion is accurate with no zoom"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=1.0
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=1.0
         )
-        
+
         # Start with page coordinates
         orig_page_x, orig_page_y = 123.45, 678.90
-        
+
         # Convert to screen and back
         screen_x, screen_y = renderer.page_to_screen(orig_page_x, orig_page_y)
         page_x, page_y = renderer.screen_to_page(screen_x, screen_y)
-        
+
         # Should get back the original values
         assert abs(page_x - orig_page_x) < 0.001
         assert abs(page_y - orig_page_y) < 0.001
-    
+
     def test_roundtrip_conversion_with_zoom(self):
         """Test that page->screen->page conversion is accurate with zoom"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=1.5
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=1.5
         )
-        
+
         # Start with page coordinates
         orig_page_x, orig_page_y = 123.45, 678.90
-        
+
         # Convert to screen and back
         screen_x, screen_y = renderer.page_to_screen(orig_page_x, orig_page_y)
         page_x, page_y = renderer.screen_to_page(screen_x, screen_y)
-        
+
         # Should get back the original values (with floating point tolerance)
         assert abs(page_x - orig_page_x) < 0.001
         assert abs(page_y - orig_page_y) < 0.001
-    
+
     def test_roundtrip_conversion_extreme_zoom(self):
         """Test coordinate conversion with extreme zoom levels"""
         for zoom in [0.1, 0.5, 1.0, 2.0, 5.0]:
             renderer = PageRenderer(
-                page_width_mm=210.0,
-                page_height_mm=297.0,
-                screen_x=50.0,
-                screen_y=100.0,
-                dpi=96,
-                zoom=zoom
+                page_width_mm=210.0, page_height_mm=297.0, screen_x=50.0, screen_y=100.0, dpi=96, zoom=zoom
             )
-            
+
             orig_page_x, orig_page_y = 250.0, 400.0
             screen_x, screen_y = renderer.page_to_screen(orig_page_x, orig_page_y)
             page_x, page_y = renderer.screen_to_page(screen_x, screen_y)
-            
+
             assert abs(page_x - orig_page_x) < 0.001
             assert abs(page_y - orig_page_y) < 0.001
 
 
 class TestPageRendererBounds:
     """Test page bounds and point detection"""
-    
+
     def test_is_point_in_page_inside(self):
         """Test is_point_in_page for points inside the page"""
         renderer = PageRenderer(
@@ -174,108 +134,85 @@ class TestPageRendererBounds:
             screen_x=100.0,
             screen_y=200.0,
             dpi=96,
-            zoom=1.0
+            zoom=1.0,
         )
-        
+
         # Calculate page dimensions in pixels
         page_width_px = 210.0 * 96 / 25.4  # ~794 pixels
         page_height_px = 297.0 * 96 / 25.4  # ~1123 pixels
-        
+
         # Point in center should be inside
         center_x = 100.0 + page_width_px / 2
         center_y = 200.0 + page_height_px / 2
         assert renderer.is_point_in_page(center_x, center_y)
-        
+
         # Point at origin should be inside
         assert renderer.is_point_in_page(100.0, 200.0)
-        
+
         # Point at bottom-right corner should be inside
-        assert renderer.is_point_in_page(
-            100.0 + page_width_px,
-            200.0 + page_height_px
-        )
-    
+        assert renderer.is_point_in_page(100.0 + page_width_px, 200.0 + page_height_px)
+
     def test_is_point_in_page_outside(self):
         """Test is_point_in_page for points outside the page"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=1.0
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=1.0
         )
-        
+
         # Point before page start
         assert not renderer.is_point_in_page(50.0, 150.0)
-        
+
         # Point way beyond page
         assert not renderer.is_point_in_page(2000.0, 2000.0)
-        
+
         # Point to the left of page
         assert not renderer.is_point_in_page(50.0, 500.0)
-        
+
         # Point above page
         assert not renderer.is_point_in_page(500.0, 150.0)
-    
+
     def test_is_point_in_page_with_zoom(self):
         """Test is_point_in_page with different zoom levels"""
         for zoom in [0.5, 1.0, 2.0]:
             renderer = PageRenderer(
-                page_width_mm=210.0,
-                page_height_mm=297.0,
-                screen_x=100.0,
-                screen_y=200.0,
-                dpi=96,
-                zoom=zoom
+                page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=zoom
             )
-            
+
             # Center of page should always be inside regardless of zoom
             page_width_px = 210.0 * 96 / 25.4
             page_height_px = 297.0 * 96 / 25.4
             center_x = 100.0 + (page_width_px * zoom) / 2
             center_y = 200.0 + (page_height_px * zoom) / 2
             assert renderer.is_point_in_page(center_x, center_y)
-    
+
     def test_get_page_bounds_screen(self):
         """Test get_page_bounds_screen returns correct screen coordinates"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=1.5
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=1.5
         )
-        
+
         x, y, w, h = renderer.get_page_bounds_screen()
-        
+
         assert x == 100.0
         assert y == 200.0
-        
+
         # Width and height should be scaled by zoom
         page_width_px = 210.0 * 96 / 25.4
         page_height_px = 297.0 * 96 / 25.4
         assert abs(w - page_width_px * 1.5) < 0.1
         assert abs(h - page_height_px * 1.5) < 0.1
-    
+
     def test_get_page_bounds_page(self):
         """Test get_page_bounds_page returns correct page-local coordinates"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=1.5
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=1.5
         )
-        
+
         x, y, w, h = renderer.get_page_bounds_page()
-        
+
         # Origin should be at 0,0 in page-local coordinates
         assert x == 0.0
         assert y == 0.0
-        
+
         # Width and height should NOT be affected by zoom (page-local coords)
         page_width_px = 210.0 * 96 / 25.4
         page_height_px = 297.0 * 96 / 25.4
@@ -285,22 +222,17 @@ class TestPageRendererBounds:
 
 class TestPageRendererSubPages:
     """Test sub-page detection for facing pages"""
-    
+
     def test_get_sub_page_at_single_page(self):
         """Test that get_sub_page_at returns None for single pages"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=1.0
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=1.0
         )
-        
+
         # For non-facing pages, should return None
         result = renderer.get_sub_page_at(500.0, is_facing_page=False)
         assert result is None
-    
+
     def test_get_sub_page_at_facing_page_left(self):
         """Test get_sub_page_at for left side of facing page"""
         renderer = PageRenderer(
@@ -309,17 +241,17 @@ class TestPageRendererSubPages:
             screen_x=100.0,
             screen_y=200.0,
             dpi=96,
-            zoom=1.0
+            zoom=1.0,
         )
-        
+
         # Calculate center line
         page_width_px = 420.0 * 96 / 25.4
         center_x = 100.0 + page_width_px / 2
-        
+
         # Point before center should be 'left'
         result = renderer.get_sub_page_at(center_x - 10, is_facing_page=True)
-        assert result == 'left'
-    
+        assert result == "left"
+
     def test_get_sub_page_at_facing_page_right(self):
         """Test get_sub_page_at for right side of facing page"""
         renderer = PageRenderer(
@@ -328,21 +260,21 @@ class TestPageRendererSubPages:
             screen_x=100.0,
             screen_y=200.0,
             dpi=96,
-            zoom=1.0
+            zoom=1.0,
         )
-        
+
         # Calculate center line
         page_width_px = 420.0 * 96 / 25.4
         center_x = 100.0 + page_width_px / 2
-        
+
         # Point after center should be 'right'
         result = renderer.get_sub_page_at(center_x + 10, is_facing_page=True)
-        assert result == 'right'
+        assert result == "right"
 
 
 class TestPageRendererDimensions:
     """Test page dimension calculations"""
-    
+
     def test_page_dimensions_calculated_correctly(self):
         """Test that page dimensions are calculated correctly from mm to pixels"""
         renderer = PageRenderer(
@@ -351,113 +283,86 @@ class TestPageRendererDimensions:
             screen_x=0.0,
             screen_y=0.0,
             dpi=96,
-            zoom=1.0
+            zoom=1.0,
         )
-        
+
         # A4 at 96 DPI
         expected_width = 210.0 * 96 / 25.4  # ~794 pixels
         expected_height = 297.0 * 96 / 25.4  # ~1123 pixels
-        
+
         assert abs(renderer.page_width_px - expected_width) < 0.1
         assert abs(renderer.page_height_px - expected_height) < 0.1
-    
+
     def test_screen_dimensions_with_zoom(self):
         """Test that screen dimensions account for zoom"""
-        renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=0.0,
-            screen_y=0.0,
-            dpi=96,
-            zoom=2.0
-        )
-        
+        renderer = PageRenderer(page_width_mm=210.0, page_height_mm=297.0, screen_x=0.0, screen_y=0.0, dpi=96, zoom=2.0)
+
         # Screen dimensions should be doubled due to zoom
         expected_width = (210.0 * 96 / 25.4) * 2.0
         expected_height = (297.0 * 96 / 25.4) * 2.0
-        
+
         assert abs(renderer.screen_width - expected_width) < 0.1
         assert abs(renderer.screen_height - expected_height) < 0.1
-    
+
     def test_different_dpi_values(self):
         """Test page dimensions with different DPI values"""
         dpi_values = [72, 96, 150, 300]
-        
+
         for dpi in dpi_values:
             renderer = PageRenderer(
-                page_width_mm=210.0,
-                page_height_mm=297.0,
-                screen_x=0.0,
-                screen_y=0.0,
-                dpi=dpi,
-                zoom=1.0
+                page_width_mm=210.0, page_height_mm=297.0, screen_x=0.0, screen_y=0.0, dpi=dpi, zoom=1.0
             )
-            
+
             expected_width = 210.0 * dpi / 25.4
             expected_height = 297.0 * dpi / 25.4
-            
+
             assert abs(renderer.page_width_px - expected_width) < 0.1
             assert abs(renderer.page_height_px - expected_height) < 0.1
 
 
 class TestPageRendererEdgeCases:
     """Test edge cases and boundary conditions"""
-    
+
     def test_zero_coordinates(self):
         """Test handling of zero coordinates"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=1.0
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=1.0
         )
-        
+
         screen_x, screen_y = renderer.page_to_screen(0, 0)
         assert screen_x == 100.0
         assert screen_y == 200.0
-        
+
         page_x, page_y = renderer.screen_to_page(100.0, 200.0)
         assert page_x == 0.0
         assert page_y == 0.0
-    
+
     def test_negative_page_coordinates(self):
         """Test handling of negative page coordinates"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=1.0
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=1.0
         )
-        
+
         # Negative page coordinates should still convert correctly
         screen_x, screen_y = renderer.page_to_screen(-50, -75)
         assert screen_x == 50.0
         assert screen_y == 125.0
-        
+
         # And back again
         page_x, page_y = renderer.screen_to_page(50.0, 125.0)
         assert page_x == -50.0
         assert page_y == -75.0
-    
+
     def test_very_large_coordinates(self):
         """Test handling of very large coordinates"""
         renderer = PageRenderer(
-            page_width_mm=210.0,
-            page_height_mm=297.0,
-            screen_x=100.0,
-            screen_y=200.0,
-            dpi=96,
-            zoom=1.0
+            page_width_mm=210.0, page_height_mm=297.0, screen_x=100.0, screen_y=200.0, dpi=96, zoom=1.0
         )
-        
+
         large_x, large_y = 10000.0, 20000.0
-        
+
         screen_x, screen_y = renderer.page_to_screen(large_x, large_y)
         page_x, page_y = renderer.screen_to_page(screen_x, screen_y)
-        
+
         assert abs(page_x - large_x) < 0.001
         assert abs(page_y - large_y) < 0.001
diff --git a/tests/test_page_setup_dialog.py b/tests/test_page_setup_dialog.py
index 08e0ea6..d780715 100644
--- a/tests/test_page_setup_dialog.py
+++ b/tests/test_page_setup_dialog.py
@@ -190,16 +190,16 @@ class TestPageSetupDialog:
         values = dialog.get_values()
 
         # Check all values returned
-        assert values['selected_index'] == 0
-        assert values['selected_page'] == page
-        assert values['is_cover'] is True
-        assert values['paper_thickness_mm'] == 0.15
-        assert values['cover_bleed_mm'] == 5.0
-        assert values['width_mm'] == 200
-        assert values['height_mm'] == 280
-        assert values['working_dpi'] == 150
-        assert values['export_dpi'] == 600
-        assert values['set_as_default'] is True
+        assert values["selected_index"] == 0
+        assert values["selected_page"] == page
+        assert values["is_cover"] is True
+        assert values["paper_thickness_mm"] == 0.15
+        assert values["cover_bleed_mm"] == 5.0
+        assert values["width_mm"] == 200
+        assert values["height_mm"] == 280
+        assert values["working_dpi"] == 150
+        assert values["export_dpi"] == 600
+        assert values["set_as_default"] is True
 
     def test_dialog_page_change_updates_values(self, qtbot):
         """Test changing selected page updates displayed values"""
@@ -240,14 +240,14 @@ class TestDialogMixin:
         # Create mock dialog with get_values as a proper method
         mock_dialog = MagicMock(spec=QDialog)
         mock_dialog.exec = Mock(return_value=QDialog.DialogCode.Accepted)
-        mock_dialog.get_values = Mock(return_value={'test': 'value'})
+        mock_dialog.get_values = Mock(return_value={"test": "value"})
 
         # Mock dialog class
         mock_dialog_class = Mock(return_value=mock_dialog)
 
         result = window.create_dialog(mock_dialog_class)
 
-        assert result == {'test': 'value'}
+        assert result == {"test": "value"}
         mock_dialog.exec.assert_called_once()
 
     def test_dialog_mixin_create_dialog_rejected(self, qtbot):
@@ -283,7 +283,7 @@ class TestDialogMixin:
         # Create mock dialog with get_values as a proper method
         mock_dialog = MagicMock(spec=QDialog)
         mock_dialog.exec = Mock(return_value=QDialog.DialogCode.Accepted)
-        mock_dialog.get_values = Mock(return_value={'test': 'value'})
+        mock_dialog.get_values = Mock(return_value={"test": "value"})
 
         # Mock dialog class
         mock_dialog_class = Mock(return_value=mock_dialog)
@@ -294,7 +294,7 @@ class TestDialogMixin:
         result = window.show_dialog(mock_dialog_class, on_accept=callback)
 
         assert result is True
-        callback.assert_called_once_with({'test': 'value'})
+        callback.assert_called_once_with({"test": "value"})
 
 
 class TestDialogActionDecorator:
@@ -362,7 +362,7 @@ class TestDialogMixinEdgeCases:
 
         mock_dialog = MagicMock(spec=QDialog)
         mock_dialog.exec = Mock(return_value=QDialog.DialogCode.Accepted)
-        mock_dialog.get_values = Mock(return_value={'data': 'test'})
+        mock_dialog.get_values = Mock(return_value={"data": "test"})
 
         mock_dialog_class = Mock(return_value=mock_dialog)
 
@@ -370,7 +370,7 @@ class TestDialogMixinEdgeCases:
 
         # Verify setWindowTitle was called
         mock_dialog.setWindowTitle.assert_called_once_with("Custom Title")
-        assert result == {'data': 'test'}
+        assert result == {"data": "test"}
 
     def test_show_dialog_rejected(self, qtbot):
         """Test show_dialog when user rejects dialog"""
@@ -543,16 +543,16 @@ class TestPageSetupIntegration:
 
         # Create mock values that would come from dialog
         values = {
-            'selected_index': 0,
-            'selected_page': window.project.pages[0],
-            'is_cover': False,
-            'paper_thickness_mm': 0.15,
-            'cover_bleed_mm': 5.0,
-            'width_mm': 200,
-            'height_mm': 280,
-            'working_dpi': 150,
-            'export_dpi': 600,
-            'set_as_default': True
+            "selected_index": 0,
+            "selected_page": window.project.pages[0],
+            "is_cover": False,
+            "paper_thickness_mm": 0.15,
+            "cover_bleed_mm": 5.0,
+            "width_mm": 200,
+            "height_mm": 280,
+            "working_dpi": 150,
+            "export_dpi": 600,
+            "set_as_default": True,
         }
 
         # Access the unwrapped function to test business logic directly
@@ -564,7 +564,7 @@ class TestPageSetupIntegration:
         original_func = window.page_setup
         # Decorators return wrappers, but we can call them with values directly
         # by accessing the innermost wrapped function
-        while hasattr(original_func, '__wrapped__'):
+        while hasattr(original_func, "__wrapped__"):
             original_func = original_func.__wrapped__
 
         # If no __wrapped__, the decorator system is different
@@ -575,7 +575,7 @@ class TestPageSetupIntegration:
         # Get the undecorated method from the class
         undecorated_page_setup = page_ops.PageOperationsMixin.page_setup
         # Find the innermost function
-        while hasattr(undecorated_page_setup, '__wrapped__'):
+        while hasattr(undecorated_page_setup, "__wrapped__"):
             undecorated_page_setup = undecorated_page_setup.__wrapped__
 
         # Call the business logic directly
@@ -635,22 +635,23 @@ class TestPageSetupIntegration:
 
         # Test designating first page as cover
         values = {
-            'selected_index': 0,
-            'selected_page': window.project.pages[0],
-            'is_cover': True,  # Designate as cover
-            'paper_thickness_mm': 0.1,
-            'cover_bleed_mm': 3.0,
-            'width_mm': 210,
-            'height_mm': 297,
-            'working_dpi': 96,
-            'export_dpi': 300,
-            'set_as_default': False
+            "selected_index": 0,
+            "selected_page": window.project.pages[0],
+            "is_cover": True,  # Designate as cover
+            "paper_thickness_mm": 0.1,
+            "cover_bleed_mm": 3.0,
+            "width_mm": 210,
+            "height_mm": 297,
+            "working_dpi": 96,
+            "export_dpi": 300,
+            "set_as_default": False,
         }
 
         # Get the undecorated method
         from pyPhotoAlbum.mixins.operations import page_ops
+
         undecorated_page_setup = page_ops.PageOperationsMixin.page_setup
-        while hasattr(undecorated_page_setup, '__wrapped__'):
+        while hasattr(undecorated_page_setup, "__wrapped__"):
             undecorated_page_setup = undecorated_page_setup.__wrapped__
 
         # Mock update_cover_dimensions
@@ -706,21 +707,22 @@ class TestPageSetupIntegration:
 
         # Test changing double spread page size
         values = {
-            'selected_index': 0,
-            'selected_page': window.project.pages[0],
-            'is_cover': False,
-            'paper_thickness_mm': 0.1,
-            'cover_bleed_mm': 3.0,
-            'width_mm': 200,  # New base width
-            'height_mm': 280,  # New height
-            'working_dpi': 96,
-            'export_dpi': 300,
-            'set_as_default': False
+            "selected_index": 0,
+            "selected_page": window.project.pages[0],
+            "is_cover": False,
+            "paper_thickness_mm": 0.1,
+            "cover_bleed_mm": 3.0,
+            "width_mm": 200,  # New base width
+            "height_mm": 280,  # New height
+            "working_dpi": 96,
+            "export_dpi": 300,
+            "set_as_default": False,
         }
 
         from pyPhotoAlbum.mixins.operations import page_ops
+
         undecorated_page_setup = page_ops.PageOperationsMixin.page_setup
-        while hasattr(undecorated_page_setup, '__wrapped__'):
+        while hasattr(undecorated_page_setup, "__wrapped__"):
             undecorated_page_setup = undecorated_page_setup.__wrapped__
 
         undecorated_page_setup(window, values)
diff --git a/tests/test_page_setup_dialog_mocked.py b/tests/test_page_setup_dialog_mocked.py
index c924db4..fcc7982 100644
--- a/tests/test_page_setup_dialog_mocked.py
+++ b/tests/test_page_setup_dialog_mocked.py
@@ -26,7 +26,7 @@ class TestPageSetupDialogWithMocks:
 
         # We can verify the class signature and that it would accept these params
         # This is a structural test rather than a full initialization test
-        assert hasattr(PageSetupDialog, '__init__')
+        assert hasattr(PageSetupDialog, "__init__")
 
         # The actual widget creation tests are in test_page_setup_dialog.py
         # using qtbot which handles Qt properly
@@ -44,7 +44,7 @@ class TestPageSetupDialogWithMocks:
         project.pages = [page1, page2]
 
         # Mock the dialog instance
-        with patch.object(PageSetupDialog, '__init__', lambda self, *args, **kwargs: None):
+        with patch.object(PageSetupDialog, "__init__", lambda self, *args, **kwargs: None):
             dialog = PageSetupDialog(None, None, 0)
 
             # Manually set required attributes
@@ -88,7 +88,7 @@ class TestPageSetupDialogWithMocks:
         page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         project.pages = [page]
 
-        with patch.object(PageSetupDialog, '__init__', lambda self, *args, **kwargs: None):
+        with patch.object(PageSetupDialog, "__init__", lambda self, *args, **kwargs: None):
             dialog = PageSetupDialog(None, None, 0)
             dialog.project = project
             dialog._cover_group = Mock()
@@ -112,11 +112,11 @@ class TestPageSetupDialogWithMocks:
 
         # Create 3 content pages (not covers)
         for i in range(3):
-            page = Page(layout=PageLayout(width=210, height=297), page_number=i+1)
+            page = Page(layout=PageLayout(width=210, height=297), page_number=i + 1)
             page.is_cover = False
             project.pages.append(page)
 
-        with patch.object(PageSetupDialog, '__init__', lambda self, *args, **kwargs: None):
+        with patch.object(PageSetupDialog, "__init__", lambda self, *args, **kwargs: None):
             dialog = PageSetupDialog(None, None, 0)
             dialog.project = project
             dialog.cover_checkbox = Mock()
@@ -158,7 +158,7 @@ class TestPageSetupDialogWithMocks:
         page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         project.pages = [page]
 
-        with patch.object(PageSetupDialog, '__init__', lambda self, *args, **kwargs: None):
+        with patch.object(PageSetupDialog, "__init__", lambda self, *args, **kwargs: None):
             dialog = PageSetupDialog(None, None, 0)
             dialog.project = project
 
@@ -194,16 +194,16 @@ class TestPageSetupDialogWithMocks:
             values = dialog.get_values()
 
             # Verify all values were extracted
-            assert values['selected_index'] == 0
-            assert values['selected_page'] == page
-            assert values['is_cover'] is True
-            assert values['paper_thickness_mm'] == 0.15
-            assert values['cover_bleed_mm'] == 5.0
-            assert values['width_mm'] == 200.0
-            assert values['height_mm'] == 280.0
-            assert values['working_dpi'] == 150
-            assert values['export_dpi'] == 600
-            assert values['set_as_default'] is True
+            assert values["selected_index"] == 0
+            assert values["selected_page"] == page
+            assert values["is_cover"] is True
+            assert values["paper_thickness_mm"] == 0.15
+            assert values["cover_bleed_mm"] == 5.0
+            assert values["width_mm"] == 200.0
+            assert values["height_mm"] == 280.0
+            assert values["working_dpi"] == 150
+            assert values["export_dpi"] == 600
+            assert values["set_as_default"] is True
 
     def test_cover_page_width_display(self):
         """Test cover page shows full width, not base width"""
@@ -217,7 +217,7 @@ class TestPageSetupDialogWithMocks:
         page.is_cover = True
         project.pages = [page]
 
-        with patch.object(PageSetupDialog, '__init__', lambda self, *args, **kwargs: None):
+        with patch.object(PageSetupDialog, "__init__", lambda self, *args, **kwargs: None):
             dialog = PageSetupDialog(None, None, 0)
             dialog.project = project
             dialog._cover_group = Mock()
@@ -259,7 +259,7 @@ class TestDialogMixinMocked:
         # Mock dialog class
         mock_dialog_instance = Mock()
         mock_dialog_instance.exec.return_value = 1  # Accepted
-        mock_dialog_instance.get_values.return_value = {'key': 'value'}
+        mock_dialog_instance.get_values.return_value = {"key": "value"}
 
         mock_dialog_class = Mock(return_value=mock_dialog_instance)
 
@@ -279,7 +279,7 @@ class TestDialogMixinMocked:
         mock_dialog_instance.get_values.assert_called_once()
 
         # Verify result
-        assert result == {'key': 'value'}
+        assert result == {"key": "value"}
 
     def test_show_dialog_with_callback_flow(self):
         """Test show_dialog method with callback"""
@@ -293,7 +293,7 @@ class TestDialogMixinMocked:
         # Mock dialog
         mock_dialog_instance = Mock()
         mock_dialog_instance.exec.return_value = 1  # Accepted
-        mock_dialog_instance.get_values.return_value = {'data': 'test'}
+        mock_dialog_instance.get_values.return_value = {"data": "test"}
 
         mock_dialog_class = Mock(return_value=mock_dialog_instance)
 
@@ -304,7 +304,7 @@ class TestDialogMixinMocked:
         result = window.show_dialog(mock_dialog_class, on_accept=callback, param="value")
 
         # Verify callback was called with dialog values
-        callback.assert_called_once_with({'data': 'test'})
+        callback.assert_called_once_with({"data": "test"})
 
         # Verify result
         assert result is True
@@ -346,7 +346,7 @@ class TestDialogActionDecoratorMocked:
         # Mock dialog instance
         mock_dialog = Mock()
         mock_dialog.exec.return_value = QDialog.DialogCode.Accepted  # Accepted
-        mock_dialog.get_values.return_value = {'test': 'data'}
+        mock_dialog.get_values.return_value = {"test": "data"}
 
         # Mock dialog class
         mock_dialog_cls = Mock(return_value=mock_dialog)
@@ -354,7 +354,7 @@ class TestDialogActionDecoratorMocked:
         # Create decorated function
         @dialog_action(dialog_class=mock_dialog_cls, requires_pages=True)
         def test_function(self, values):
-            return values['test']
+            return values["test"]
 
         # Mock instance with required attributes
         instance = Mock()
@@ -375,7 +375,7 @@ class TestDialogActionDecoratorMocked:
         mock_dialog.get_values.assert_called_once()
 
         # Verify original function received values
-        assert result == 'data'
+        assert result == "data"
 
     def test_decorator_returns_early_when_no_pages(self):
         """Test decorator returns early when pages required but not present"""
@@ -407,7 +407,7 @@ class TestDialogActionDecoratorMocked:
 
         mock_dialog = Mock()
         mock_dialog.exec.return_value = 1
-        mock_dialog.get_values.return_value = {'key': 'val'}
+        mock_dialog.get_values.return_value = {"key": "val"}
 
         mock_dialog_cls = Mock(return_value=mock_dialog)
 
@@ -427,8 +427,8 @@ class TestDialogActionDecoratorMocked:
         mock_dialog_cls.assert_called_once()
 
         # Verify result
-        assert result == {'key': 'val'}
+        assert result == {"key": "val"}
 
 
-if __name__ == '__main__':
-    pytest.main([__file__, '-v'])
+if __name__ == "__main__":
+    pytest.main([__file__, "-v"])
diff --git a/tests/test_pdf_export.py b/tests/test_pdf_export.py
index cd729bb..228f86b 100755
--- a/tests/test_pdf_export.py
+++ b/tests/test_pdf_export.py
@@ -15,27 +15,27 @@ def test_pdf_exporter_basic():
     # Create a simple project
     project = Project("Test Project")
     project.page_size_mm = (210, 297)  # A4
-    
+
     # Add a single page
     page = Page(page_number=1, is_double_spread=False)
     project.add_page(page)
-    
+
     # Export to temporary file
-    with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as tmp:
+    with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as tmp:
         tmp_path = tmp.name
-    
+
     try:
         exporter = PDFExporter(project)
         success, warnings = exporter.export(tmp_path)
-        
+
         assert success, f"Export failed: {warnings}"
         assert os.path.exists(tmp_path), "PDF file was not created"
         assert os.path.getsize(tmp_path) > 0, "PDF file is empty"
-        
+
         print(f"✓ Basic PDF export successful: {tmp_path}")
         if warnings:
             print(f"  Warnings: {warnings}")
-    
+
     finally:
         if os.path.exists(tmp_path):
             os.remove(tmp_path)
@@ -45,26 +45,26 @@ def test_pdf_exporter_double_spread():
     """Test PDF export with double-page spread"""
     project = Project("Test Spread Project")
     project.page_size_mm = (210, 297)  # A4
-    
+
     # Add a double-page spread
     spread_page = Page(page_number=1, is_double_spread=True)
     project.add_page(spread_page)
-    
+
     # Export to temporary file
-    with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as tmp:
+    with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as tmp:
         tmp_path = tmp.name
-    
+
     try:
         exporter = PDFExporter(project)
         success, warnings = exporter.export(tmp_path)
-        
+
         assert success, f"Export failed: {warnings}"
         assert os.path.exists(tmp_path), "PDF file was not created"
-        
+
         print(f"✓ Double-spread PDF export successful: {tmp_path}")
         if warnings:
             print(f"  Warnings: {warnings}")
-    
+
     finally:
         if os.path.exists(tmp_path):
             os.remove(tmp_path)
@@ -83,14 +83,17 @@ def test_pdf_exporter_with_text():
         text_content="Hello, World!",
         font_settings={"family": "Helvetica", "size": 24, "color": (0, 0, 0)},
         alignment="center",
-        x=50, y=50, width=100, height=30
+        x=50,
+        y=50,
+        width=100,
+        height=30,
     )
     page.layout.add_element(text_box)
 
     project.add_page(page)
 
     # Export to temporary file
-    with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as tmp:
+    with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as tmp:
         tmp_path = tmp.name
 
     try:
@@ -143,7 +146,7 @@ def test_pdf_text_position_and_size():
         x=text_box_x_px,
         y=text_box_y_px,
         width=text_box_width_px,
-        height=text_box_height_px
+        height=text_box_height_px,
     )
     page.layout.add_element(text_box)
     project.add_page(page)
@@ -168,7 +171,7 @@ def test_pdf_text_position_and_size():
     expected_font_size_pt = font_size_px * 25.4 / dpi * MM_TO_POINTS
 
     # Export to temporary file
-    with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as tmp:
+    with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as tmp:
         tmp_path = tmp.name
 
     try:
@@ -186,16 +189,20 @@ def test_pdf_text_position_and_size():
 
             # Get the first character's position and font size
             first_char = chars[0]
-            text_x = first_char['x0']
-            text_y_baseline = first_char['y0']  # This is the baseline y position
-            actual_font_size = first_char['size']
+            text_x = first_char["x0"]
+            text_y_baseline = first_char["y0"]  # This is the baseline y position
+            actual_font_size = first_char["size"]
 
             print(f"\nText Position Analysis:")
-            print(f"  Text box (in pixels at {dpi} DPI): x={text_box_x_px}, y={text_box_y_px}, "
-                  f"w={text_box_width_px}, h={text_box_height_px}")
-            print(f"  Text box (in PDF points): x={text_box_x_pt:.1f}, "
-                  f"y_bottom={text_box_y_pt_bottom:.1f}, y_top={text_box_y_pt_top:.1f}, "
-                  f"height={text_box_height_pt:.1f}")
+            print(
+                f"  Text box (in pixels at {dpi} DPI): x={text_box_x_px}, y={text_box_y_px}, "
+                f"w={text_box_width_px}, h={text_box_height_px}"
+            )
+            print(
+                f"  Text box (in PDF points): x={text_box_x_pt:.1f}, "
+                f"y_bottom={text_box_y_pt_bottom:.1f}, y_top={text_box_y_pt_top:.1f}, "
+                f"height={text_box_height_pt:.1f}"
+            )
             print(f"  Font size (pixels): {font_size_px}")
             print(f"  Expected font size (points): {expected_font_size_pt:.1f}")
             print(f"  Actual font size (points): {actual_font_size:.1f}")
@@ -213,8 +220,7 @@ def test_pdf_text_position_and_size():
             # Verify text X position is near the left edge of the text box
             x_diff = abs(text_x - text_box_x_pt)
             assert x_diff < 5.0, (
-                f"Text X position mismatch: expected ~{text_box_x_pt:.1f}, "
-                f"got {text_x:.1f} (diff: {x_diff:.1f}pt)"
+                f"Text X position mismatch: expected ~{text_box_x_pt:.1f}, " f"got {text_x:.1f} (diff: {x_diff:.1f}pt)"
             )
 
             # Verify text Y baseline is INSIDE the text box (not above it)
@@ -280,7 +286,7 @@ def test_pdf_text_wrapping():
         x=text_box_x_px,
         y=text_box_y_px,
         width=text_box_width_px,
-        height=text_box_height_px
+        height=text_box_height_px,
     )
     page.layout.add_element(text_box)
     project.add_page(page)
@@ -296,7 +302,7 @@ def test_pdf_text_wrapping():
     text_box_right_pt = text_box_x_pt + text_box_width_pt
 
     # Export to temporary file
-    with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as tmp:
+    with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as tmp:
         tmp_path = tmp.name
 
     try:
@@ -313,7 +319,7 @@ def test_pdf_text_wrapping():
             assert len(chars) > 0, "No text found in PDF"
 
             # Get all unique Y positions (lines)
-            y_positions = sorted(set(round(c['top'], 1) for c in chars))
+            y_positions = sorted(set(round(c["top"], 1) for c in chars))
 
             print(f"\nText Wrapping Analysis:")
             print(f"  Text box width: {text_box_width_pt:.1f}pt")
@@ -322,21 +328,19 @@ def test_pdf_text_wrapping():
             print(f"  Line Y positions: {y_positions[:5]}...")  # Show first 5
 
             # Verify text wrapped to multiple lines
-            assert len(y_positions) > 1, (
-                f"Text should wrap to multiple lines but only found {len(y_positions)} line(s)"
-            )
+            assert len(y_positions) > 1, f"Text should wrap to multiple lines but only found {len(y_positions)} line(s)"
 
             # Verify all characters are within box width (with small tolerance)
             tolerance = 5.0  # Small tolerance for rounding
             for char in chars:
-                char_x = char['x0']
-                char_right = char['x1']
-                assert char_x >= text_box_x_pt - tolerance, (
-                    f"Character '{char['text']}' at x={char_x:.1f} is left of box start {text_box_x_pt:.1f}"
-                )
-                assert char_right <= text_box_right_pt + tolerance, (
-                    f"Character '{char['text']}' ends at x={char_right:.1f} which exceeds box right {text_box_right_pt:.1f}"
-                )
+                char_x = char["x0"]
+                char_right = char["x1"]
+                assert (
+                    char_x >= text_box_x_pt - tolerance
+                ), f"Character '{char['text']}' at x={char_x:.1f} is left of box start {text_box_x_pt:.1f}"
+                assert (
+                    char_right <= text_box_right_pt + tolerance
+                ), f"Character '{char['text']}' ends at x={char_right:.1f} which exceeds box right {text_box_right_pt:.1f}"
 
             print(f"  All characters within box width: ✓")
             print(f"\n✓ Text wrapping test passed!")
@@ -354,28 +358,28 @@ def test_pdf_exporter_facing_pages_alignment():
     # Add single page (page 1)
     page1 = Page(page_number=1, is_double_spread=False)
     project.add_page(page1)
-    
+
     # Add double spread (should start on page 2, which requires blank insert)
     # Since page 1 is odd, a blank page should be inserted, making the spread pages 2-3
     spread = Page(page_number=2, is_double_spread=True)
     project.add_page(spread)
-    
+
     # Export to temporary file
-    with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as tmp:
+    with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as tmp:
         tmp_path = tmp.name
-    
+
     try:
         exporter = PDFExporter(project)
         success, warnings = exporter.export(tmp_path)
-        
+
         assert success, f"Export failed: {warnings}"
         assert os.path.exists(tmp_path), "PDF file was not created"
-        
+
         print(f"✓ Facing pages alignment successful: {tmp_path}")
         print(f"  Expected: Page 1 (single), blank page, Pages 2-3 (spread)")
         if warnings:
             print(f"  Warnings: {warnings}")
-    
+
     finally:
         if os.path.exists(tmp_path):
             os.remove(tmp_path)
@@ -385,34 +389,31 @@ def test_pdf_exporter_missing_image():
     """Test PDF export with missing image (should warn but not fail)"""
     project = Project("Test Missing Image")
     project.page_size_mm = (210, 297)
-    
+
     # Create page with image that doesn't exist
     page = Page(page_number=1, is_double_spread=False)
-    
+
     # Add image with non-existent path
-    image = ImageData(
-        image_path="/nonexistent/path/to/image.jpg",
-        x=50, y=50, width=100, height=100
-    )
+    image = ImageData(image_path="/nonexistent/path/to/image.jpg", x=50, y=50, width=100, height=100)
     page.layout.add_element(image)
-    
+
     project.add_page(page)
-    
+
     # Export to temporary file
-    with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as tmp:
+    with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as tmp:
         tmp_path = tmp.name
-    
+
     try:
         exporter = PDFExporter(project)
         success, warnings = exporter.export(tmp_path)
-        
+
         assert success, "Export should succeed even with missing images"
         assert len(warnings) > 0, "Should have warnings for missing image"
         assert "not found" in warnings[0].lower(), "Warning should mention missing image"
-        
+
         print(f"✓ Missing image handling successful: {tmp_path}")
         print(f"  Warnings: {warnings}")
-    
+
     finally:
         if os.path.exists(tmp_path):
             os.remove(tmp_path)
@@ -422,65 +423,59 @@ def test_pdf_exporter_spanning_image():
     """Test PDF export with image spanning across center line of double spread"""
     import tempfile
     from PIL import Image as PILImage
-    
+
     project = Project("Test Spanning Image")
     project.page_size_mm = (210, 297)  # A4
     project.working_dpi = 96  # Standard DPI
-    
+
     # Create a test image (solid color for easy verification)
-    test_img = PILImage.new('RGB', (400, 200), color='red')
-    
+    test_img = PILImage.new("RGB", (400, 200), color="red")
+
     # Save test image to temporary file
-    with tempfile.NamedTemporaryFile(suffix='.png', delete=False) as img_tmp:
+    with tempfile.NamedTemporaryFile(suffix=".png", delete=False) as img_tmp:
         img_path = img_tmp.name
         test_img.save(img_path)
-    
+
     try:
         # Create a double-page spread
         spread_page = Page(page_number=1, is_double_spread=True)
-        
+
         # Calculate center position in pixels (for a 210mm page width at 96 DPI)
         # Spread width is 2 * 210mm = 420mm
         spread_width_px = 420 * 96 / 25.4  # ~1587 pixels
         center_px = spread_width_px / 2  # ~794 pixels
-        
+
         # Add an image that spans across the center
         # Position it so it overlaps the center line
         image_width_px = 400
         image_x_px = center_px - 200  # Start 200px before center, end 200px after
-        
-        spanning_image = ImageData(
-            image_path=img_path,
-            x=image_x_px, 
-            y=100, 
-            width=image_width_px, 
-            height=200
-        )
+
+        spanning_image = ImageData(image_path=img_path, x=image_x_px, y=100, width=image_width_px, height=200)
         spread_page.layout.add_element(spanning_image)
-        
+
         project.add_page(spread_page)
-        
+
         # Export to temporary PDF
-        with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as pdf_tmp:
+        with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as pdf_tmp:
             pdf_path = pdf_tmp.name
-        
+
         try:
             exporter = PDFExporter(project)
             success, warnings = exporter.export(pdf_path)
-            
+
             assert success, f"Export failed: {warnings}"
             assert os.path.exists(pdf_path), "PDF file was not created"
-            
+
             print(f"✓ Spanning image export successful: {pdf_path}")
             print(f"  Image spans from {image_x_px:.1f}px to {image_x_px + image_width_px:.1f}px")
             print(f"  Center line at {center_px:.1f}px")
             if warnings:
                 print(f"  Warnings: {warnings}")
-        
+
         finally:
             if os.path.exists(pdf_path):
                 os.remove(pdf_path)
-    
+
     finally:
         if os.path.exists(img_path):
             os.remove(img_path)
@@ -490,71 +485,61 @@ def test_pdf_exporter_multiple_spanning_elements():
     """Test PDF export with multiple images spanning the center line"""
     import tempfile
     from PIL import Image as PILImage
-    
+
     project = Project("Test Multiple Spanning")
     project.page_size_mm = (210, 297)  # A4
     project.working_dpi = 96
-    
+
     # Create test images
-    test_img1 = PILImage.new('RGB', (300, 150), color='blue')
-    test_img2 = PILImage.new('RGB', (250, 200), color='green')
-    
-    with tempfile.NamedTemporaryFile(suffix='.png', delete=False) as img_tmp1:
+    test_img1 = PILImage.new("RGB", (300, 150), color="blue")
+    test_img2 = PILImage.new("RGB", (250, 200), color="green")
+
+    with tempfile.NamedTemporaryFile(suffix=".png", delete=False) as img_tmp1:
         img_path1 = img_tmp1.name
         test_img1.save(img_path1)
-    
-    with tempfile.NamedTemporaryFile(suffix='.png', delete=False) as img_tmp2:
+
+    with tempfile.NamedTemporaryFile(suffix=".png", delete=False) as img_tmp2:
         img_path2 = img_tmp2.name
         test_img2.save(img_path2)
-    
+
     try:
         spread_page = Page(page_number=1, is_double_spread=True)
-        
+
         # Calculate positions
         spread_width_px = 420 * 96 / 25.4
         center_px = spread_width_px / 2
-        
+
         # First spanning image
         image1 = ImageData(
-            image_path=img_path1,
-            x=center_px - 150,  # Centered on split line
-            y=50,
-            width=300,
-            height=150
+            image_path=img_path1, x=center_px - 150, y=50, width=300, height=150  # Centered on split line
         )
-        
+
         # Second spanning image (different position)
-        image2 = ImageData(
-            image_path=img_path2,
-            x=center_px - 100,
-            y=250,
-            width=250,
-            height=200
-        )
-        
+        image2 = ImageData(image_path=img_path2, x=center_px - 100, y=250, width=250, height=200)
+
         spread_page.layout.add_element(image1)
         spread_page.layout.add_element(image2)
-        
+
         project.add_page(spread_page)
-        
-        with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as pdf_tmp:
+
+        with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as pdf_tmp:
             pdf_path = pdf_tmp.name
-        
+
         try:
             exporter = PDFExporter(project)
             success, warnings = exporter.export(pdf_path)
-            
+
             assert success, f"Export failed: {warnings}"
             assert os.path.exists(pdf_path), "PDF file was not created"
-            
+
             print(f"✓ Multiple spanning images export successful: {pdf_path}")
             if warnings:
                 print(f"  Warnings: {warnings}")
-        
+
         finally:
             if os.path.exists(pdf_path):
                 os.remove(pdf_path)
-    
+
     finally:
         if os.path.exists(img_path1):
             os.remove(img_path1)
@@ -566,52 +551,46 @@ def test_pdf_exporter_edge_case_barely_spanning():
     """Test image that barely crosses the threshold"""
     import tempfile
     from PIL import Image as PILImage
-    
+
     project = Project("Test Edge Case")
     project.page_size_mm = (210, 297)
     project.working_dpi = 96
-    
-    test_img = PILImage.new('RGB', (100, 100), color='yellow')
-    
-    with tempfile.NamedTemporaryFile(suffix='.png', delete=False) as img_tmp:
+
+    test_img = PILImage.new("RGB", (100, 100), color="yellow")
+
+    with tempfile.NamedTemporaryFile(suffix=".png", delete=False) as img_tmp:
         img_path = img_tmp.name
         test_img.save(img_path)
-    
+
     try:
         spread_page = Page(page_number=1, is_double_spread=True)
-        
+
         spread_width_px = 420 * 96 / 25.4
         center_px = spread_width_px / 2
-        
+
         # Image that just barely crosses the center line
-        image = ImageData(
-            image_path=img_path,
-            x=center_px - 5,  # Just 5px overlap
-            y=100,
-            width=100,
-            height=100
-        )
-        
+        image = ImageData(image_path=img_path, x=center_px - 5, y=100, width=100, height=100)  # Just 5px overlap
+
         spread_page.layout.add_element(image)
         project.add_page(spread_page)
-        
-        with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as pdf_tmp:
+
+        with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as pdf_tmp:
             pdf_path = pdf_tmp.name
-        
+
         try:
             exporter = PDFExporter(project)
             success, warnings = exporter.export(pdf_path)
-            
+
             assert success, f"Export failed: {warnings}"
-            
+
             print(f"✓ Edge case (barely spanning) export successful: {pdf_path}")
             if warnings:
                 print(f"  Warnings: {warnings}")
-        
+
         finally:
             if os.path.exists(pdf_path):
                 os.remove(pdf_path)
-    
+
     finally:
         if os.path.exists(img_path):
             os.remove(img_path)
@@ -622,12 +601,12 @@ def test_pdf_exporter_text_spanning():
     project = Project("Test Spanning Text")
     project.page_size_mm = (210, 297)
     project.working_dpi = 96
-    
+
     spread_page = Page(page_number=1, is_double_spread=True)
-    
+
     spread_width_px = 420 * 96 / 25.4
     center_px = spread_width_px / 2
-    
+
     # Text box spanning the center
     text_box = TextBoxData(
         text_content="Spanning Text",
@@ -636,25 +615,25 @@ def test_pdf_exporter_text_spanning():
         x=center_px - 100,
         y=100,
         width=200,
-        height=50
+        height=50,
     )
-    
+
     spread_page.layout.add_element(text_box)
     project.add_page(spread_page)
-    
-    with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as pdf_tmp:
+
+    with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as pdf_tmp:
         pdf_path = pdf_tmp.name
-    
+
     try:
         exporter = PDFExporter(project)
         success, warnings = exporter.export(pdf_path)
-        
+
         assert success, f"Export failed: {warnings}"
-        
+
         print(f"✓ Spanning text box export successful: {pdf_path}")
         if warnings:
             print(f"  Warnings: {warnings}")
-    
+
     finally:
         if os.path.exists(pdf_path):
             os.remove(pdf_path)
@@ -664,76 +643,72 @@ def test_pdf_exporter_spanning_image_aspect_ratio():
     """Test that spanning images maintain correct aspect ratio and can be recombined"""
     import tempfile
     from PIL import Image as PILImage, ImageDraw
-    
+
     project = Project("Test Aspect Ratio")
     project.page_size_mm = (210, 297)  # A4
     project.working_dpi = 96
-    
+
     # Create a distinctive test image: red left half, blue right half, with a vertical line in center
     test_width, test_height = 800, 400
-    test_img = PILImage.new('RGB', (test_width, test_height))
+    test_img = PILImage.new("RGB", (test_width, test_height))
     draw = ImageDraw.Draw(test_img)
-    
+
     # Fill left half red
     draw.rectangle([0, 0, test_width // 2, test_height], fill=(255, 0, 0))
-    
+
     # Fill right half blue
     draw.rectangle([test_width // 2, 0, test_width, test_height], fill=(0, 0, 255))
-    
+
     # Draw a black vertical line in the middle
     draw.line([test_width // 2, 0, test_width // 2, test_height], fill=(0, 0, 0), width=5)
-    
+
     # Draw horizontal reference lines for visual verification
     for y in range(0, test_height, 50):
         draw.line([0, y, test_width, y], fill=(255, 255, 255), width=2)
-    
+
     # Save test image to temporary file
-    with tempfile.NamedTemporaryFile(suffix='.png', delete=False) as img_tmp:
+    with tempfile.NamedTemporaryFile(suffix=".png", delete=False) as img_tmp:
         img_path = img_tmp.name
         test_img.save(img_path)
-    
+
     try:
         # Create a double-page spread
         spread_page = Page(page_number=1, is_double_spread=True)
-        
+
         # Calculate positions
         spread_width_px = 420 * 96 / 25.4  # ~1587 pixels
         center_px = spread_width_px / 2  # ~794 pixels
-        
+
         # Create an image element that spans the center with a specific aspect ratio
         # Make it 600px wide and 300px tall (2:1 aspect ratio)
         image_width_px = 600
         image_height_px = 300
         image_x_px = center_px - 300  # Centered on the split line
-        
+
         spanning_image = ImageData(
-            image_path=img_path,
-            x=image_x_px,
-            y=100,
-            width=image_width_px,
-            height=image_height_px
+            image_path=img_path, x=image_x_px, y=100, width=image_width_px, height=image_height_px
         )
         spread_page.layout.add_element(spanning_image)
-        
+
         project.add_page(spread_page)
-        
+
         # Export to temporary PDF
-        with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as pdf_tmp:
+        with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as pdf_tmp:
             pdf_path = pdf_tmp.name
-        
+
         try:
             exporter = PDFExporter(project)
             success, warnings = exporter.export(pdf_path)
-            
+
             assert success, f"Export failed: {warnings}"
             assert os.path.exists(pdf_path), "PDF file was not created"
-            
+
             # Verify the PDF was created and has expected properties
             # We can't easily extract and verify pixel-perfect image reconstruction without
             # additional dependencies, but we can verify the export succeeded
             file_size = os.path.getsize(pdf_path)
             assert file_size > 1000, "PDF file seems too small"
-            
+
             print(f"✓ Spanning image aspect ratio test successful: {pdf_path}")
             print(f"  Original image: {test_width}x{test_height} (aspect {test_width/test_height:.2f}:1)")
             print(f"  Element size: {image_width_px}x{image_height_px} (aspect {image_width_px/image_height_px:.2f}:1)")
@@ -741,14 +716,14 @@ def test_pdf_exporter_spanning_image_aspect_ratio():
             print(f"  Left portion: {center_px - image_x_px:.1f}px wide")
             print(f"  Right portion: {image_width_px - (center_px - image_x_px):.1f}px wide")
             print(f"  PDF size: {file_size} bytes")
-            
+
             if warnings:
                 print(f"  Warnings: {warnings}")
-                
+
         finally:
             if os.path.exists(pdf_path):
                 os.remove(pdf_path)
-    
+
     finally:
         if os.path.exists(img_path):
             os.remove(img_path)
@@ -758,74 +733,76 @@ def test_pdf_exporter_varying_aspect_ratios():
     """Test spanning images with various aspect ratios"""
     import tempfile
     from PIL import Image as PILImage, ImageDraw
-    
+
     project = Project("Test Varying Aspects")
     project.page_size_mm = (210, 297)
     project.working_dpi = 96
-    
+
     # Test different aspect ratios
     test_configs = [
-        ("Square", 400, 400),      # 1:1
-        ("Landscape", 800, 400),   # 2:1  
-        ("Portrait", 400, 800),    # 1:2
-        ("Wide", 1200, 400),       # 3:1
+        ("Square", 400, 400),  # 1:1
+        ("Landscape", 800, 400),  # 2:1
+        ("Portrait", 400, 800),  # 1:2
+        ("Wide", 1200, 400),  # 3:1
     ]
-    
+
     spread_width_px = 420 * 96 / 25.4
     center_px = spread_width_px / 2
-    
+
     for idx, (name, img_w, img_h) in enumerate(test_configs):
         # Create test image
-        test_img = PILImage.new('RGB', (img_w, img_h))
+        test_img = PILImage.new("RGB", (img_w, img_h))
         draw = ImageDraw.Draw(test_img)
-        
+
         # Different colors for each test
         colors = [(255, 0, 0), (0, 255, 0), (0, 0, 255), (255, 255, 0)]
         draw.rectangle([0, 0, img_w // 2, img_h], fill=colors[idx])
-        draw.rectangle([img_w // 2, 0, img_w, img_h], fill=(255-colors[idx][0], 255-colors[idx][1], 255-colors[idx][2]))
-        
-        with tempfile.NamedTemporaryFile(suffix='.png', delete=False) as img_tmp:
+        draw.rectangle(
+            [img_w // 2, 0, img_w, img_h], fill=(255 - colors[idx][0], 255 - colors[idx][1], 255 - colors[idx][2])
+        )
+
+        with tempfile.NamedTemporaryFile(suffix=".png", delete=False) as img_tmp:
             img_path = img_tmp.name
             test_img.save(img_path)
-        
+
         try:
             spread_page = Page(page_number=idx + 1, is_double_spread=True)
-            
+
             # Position spanning element
             element_width_px = 500
             element_height_px = int(500 * img_h / img_w)  # Maintain aspect ratio
-            
+
             spanning_image = ImageData(
                 image_path=img_path,
                 x=center_px - 250,
                 y=100 + idx * 200,
                 width=element_width_px,
-                height=element_height_px
+                height=element_height_px,
             )
             spread_page.layout.add_element(spanning_image)
-            
+
             project.add_page(spread_page)
-        
+
         finally:
             if os.path.exists(img_path):
                 os.remove(img_path)
-    
+
     # Export all pages
-    with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as pdf_tmp:
+    with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as pdf_tmp:
         pdf_path = pdf_tmp.name
-    
+
     try:
         exporter = PDFExporter(project)
         success, warnings = exporter.export(pdf_path)
-        
+
         assert success, f"Export failed: {warnings}"
         assert os.path.exists(pdf_path), "PDF file was not created"
-        
+
         print(f"✓ Varying aspect ratios test successful: {pdf_path}")
         print(f"  Tested {len(test_configs)} different aspect ratios")
         if warnings:
             print(f"  Warnings: {warnings}")
-    
+
     finally:
         if os.path.exists(pdf_path):
             os.remove(pdf_path)
@@ -842,7 +819,7 @@ def test_pdf_exporter_rotated_image():
 
     # Create a distinctive test image that shows rotation clearly
     # Make it wider than tall (400x200) so we can verify rotation
-    test_img = PILImage.new('RGB', (400, 200), color='white')
+    test_img = PILImage.new("RGB", (400, 200), color="white")
     draw = ImageDraw.Draw(test_img)
 
     # Draw a pattern that shows orientation
@@ -855,7 +832,7 @@ def test_pdf_exporter_rotated_image():
     # Yellow vertical stripe on right
     draw.rectangle([350, 0, 400, 200], fill=(255, 255, 0))
 
-    with tempfile.NamedTemporaryFile(suffix='.png', delete=False) as img_tmp:
+    with tempfile.NamedTemporaryFile(suffix=".png", delete=False) as img_tmp:
         img_path = img_tmp.name
         test_img.save(img_path)
 
@@ -865,11 +842,7 @@ def test_pdf_exporter_rotated_image():
 
         # Add image with 90-degree PIL rotation
         image = ImageData(
-            image_path=img_path,
-            x=50,
-            y=50,
-            width=200,  # These dimensions are for the rotated version
-            height=400
+            image_path=img_path, x=50, y=50, width=200, height=400  # These dimensions are for the rotated version
         )
         image.pil_rotation_90 = 1  # 90 degree rotation
         image.image_dimensions = (400, 200)  # Original dimensions before rotation
@@ -878,7 +851,7 @@ def test_pdf_exporter_rotated_image():
         project.add_page(page)
 
         # Export to PDF
-        with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as pdf_tmp:
+        with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as pdf_tmp:
             pdf_path = pdf_tmp.name
 
         try:
@@ -908,84 +881,85 @@ def test_pdf_exporter_image_downsampling():
     """Test that export DPI controls image downsampling and reduces file size"""
     import tempfile
     from PIL import Image as PILImage
-    
+
     project = Project("Test Downsampling")
     project.page_size_mm = (210, 297)  # A4
     project.working_dpi = 96
-    
+
     # Create a large test image (4000x3000 - typical high-res camera)
-    large_img = PILImage.new('RGB', (4000, 3000))
+    large_img = PILImage.new("RGB", (4000, 3000))
     # Add some pattern so it doesn't compress too much
     import random
+
     pixels = large_img.load()
     for i in range(0, 4000, 10):
         for j in range(0, 3000, 10):
             pixels[i, j] = (random.randint(0, 255), random.randint(0, 255), random.randint(0, 255))
-    
-    with tempfile.NamedTemporaryFile(suffix='.png', delete=False) as img_tmp:
+
+    with tempfile.NamedTemporaryFile(suffix=".png", delete=False) as img_tmp:
         img_path = img_tmp.name
         large_img.save(img_path)
-    
+
     try:
         # Create a page with the large image
         page = Page(page_number=1, is_double_spread=False)
-        
+
         # Add image at reasonable size (100mm x 75mm)
         image = ImageData(
             image_path=img_path,
             x=50,
             y=50,
             width=int(100 * 96 / 25.4),  # ~378 px
-            height=int(75 * 96 / 25.4)   # ~283 px
+            height=int(75 * 96 / 25.4),  # ~283 px
         )
         page.layout.add_element(image)
         project.add_page(page)
-        
+
         # Export with high DPI (300 - print quality)
-        with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as pdf_tmp1:
+        with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as pdf_tmp1:
             pdf_path_300dpi = pdf_tmp1.name
-        
+
         # Export with low DPI (150 - screen quality)
-        with tempfile.NamedTemporaryFile(suffix='.pdf', delete=False) as pdf_tmp2:
+        with tempfile.NamedTemporaryFile(suffix=".pdf", delete=False) as pdf_tmp2:
             pdf_path_150dpi = pdf_tmp2.name
-        
+
         try:
             # Export at 300 DPI
             exporter_300 = PDFExporter(project, export_dpi=300)
             success1, warnings1 = exporter_300.export(pdf_path_300dpi)
             assert success1, f"300 DPI export failed: {warnings1}"
-            
+
             # Export at 150 DPI
             exporter_150 = PDFExporter(project, export_dpi=150)
             success2, warnings2 = exporter_150.export(pdf_path_150dpi)
             assert success2, f"150 DPI export failed: {warnings2}"
-            
+
             # Check file sizes
             size_300dpi = os.path.getsize(pdf_path_300dpi)
             size_150dpi = os.path.getsize(pdf_path_150dpi)
-            
+
             print(f"✓ Image downsampling test successful:")
             print(f"  Original image: 4000x3000 pixels")
             print(f"  Element size: 100mm x 75mm")
             print(f"  PDF at 300 DPI: {size_300dpi:,} bytes")
             print(f"  PDF at 150 DPI: {size_150dpi:,} bytes")
             print(f"  Size reduction: {(1 - size_150dpi/size_300dpi)*100:.1f}%")
-            
+
             # 150 DPI should be smaller than 300 DPI
-            assert size_150dpi < size_300dpi, \
-                f"150 DPI file ({size_150dpi}) should be smaller than 300 DPI file ({size_300dpi})"
-            
+            assert (
+                size_150dpi < size_300dpi
+            ), f"150 DPI file ({size_150dpi}) should be smaller than 300 DPI file ({size_300dpi})"
+
             # 150 DPI should be significantly smaller (at least 50% reduction)
             reduction_ratio = size_150dpi / size_300dpi
-            assert reduction_ratio < 0.7, \
-                f"150 DPI should be at least 30% smaller, got {(1-reduction_ratio)*100:.1f}%"
-                
+            assert reduction_ratio < 0.7, f"150 DPI should be at least 30% smaller, got {(1-reduction_ratio)*100:.1f}%"
+
         finally:
             if os.path.exists(pdf_path_300dpi):
                 os.remove(pdf_path_300dpi)
             if os.path.exists(pdf_path_150dpi):
                 os.remove(pdf_path_150dpi)
-    
+
     finally:
         if os.path.exists(img_path):
             os.remove(img_path)
diff --git a/tests/test_project.py b/tests/test_project.py
index a3ad56f..f51d295 100755
--- a/tests/test_project.py
+++ b/tests/test_project.py
@@ -15,7 +15,7 @@ class TestPage:
         """Test Page initialization with default values"""
         layout = PageLayout()
         page = Page(layout=layout, page_number=1)
-        
+
         assert page.layout is layout
         assert page.page_number == 1
 
@@ -23,7 +23,7 @@ class TestPage:
         """Test Page initialization with custom parameters"""
         layout = PageLayout()
         page = Page(layout=layout, page_number=5)
-        
+
         assert page.layout is layout
         assert page.page_number == 5
 
@@ -32,7 +32,7 @@ class TestPage:
         layout = PageLayout()
         page = Page(layout=layout, page_number=1)
         page.page_number = 10
-        
+
         assert page.page_number == 10
 
 
@@ -42,7 +42,7 @@ class TestProject:
     def test_initialization_default(self):
         """Test Project initialization with default values"""
         project = Project()
-        
+
         assert project.name == "Untitled Project"
         assert len(project.pages) == 0
         assert project.working_dpi == 300
@@ -51,7 +51,7 @@ class TestProject:
     def test_initialization_with_name(self):
         """Test Project initialization with custom name"""
         project = Project(name="My Album")
-        
+
         assert project.name == "My Album"
 
     def test_add_page(self):
@@ -59,24 +59,24 @@ class TestProject:
         project = Project()
         layout = PageLayout()
         page = Page(layout=layout, page_number=1)
-        
+
         project.add_page(page)
-        
+
         assert len(project.pages) == 1
         assert project.pages[0] is page
 
     def test_add_multiple_pages(self):
         """Test adding multiple pages to the project"""
         project = Project()
-        
+
         page1 = Page(layout=PageLayout(), page_number=1)
         page2 = Page(layout=PageLayout(), page_number=2)
         page3 = Page(layout=PageLayout(), page_number=3)
-        
+
         project.add_page(page1)
         project.add_page(page2)
         project.add_page(page3)
-        
+
         assert len(project.pages) == 3
         assert project.pages[0] is page1
         assert project.pages[1] is page2
@@ -85,15 +85,15 @@ class TestProject:
     def test_remove_page(self):
         """Test removing a page from the project"""
         project = Project()
-        
+
         page1 = Page(layout=PageLayout(), page_number=1)
         page2 = Page(layout=PageLayout(), page_number=2)
-        
+
         project.add_page(page1)
         project.add_page(page2)
-        
+
         project.remove_page(page1)
-        
+
         assert len(project.pages) == 1
         assert project.pages[0] is page2
 
@@ -103,7 +103,7 @@ class TestProject:
         page1 = Page(layout=PageLayout(), page_number=1)
         page2 = Page(layout=PageLayout(), page_number=2)
         project.add_page(page1)
-        
+
         # Try to remove a page that was never added
         with pytest.raises(ValueError):
             project.remove_page(page2)
@@ -112,51 +112,51 @@ class TestProject:
         """Test modifying working DPI"""
         project = Project()
         project.working_dpi = 300
-        
+
         assert project.working_dpi == 300
 
     def test_page_size_modification(self):
         """Test modifying page size"""
         project = Project()
         project.page_size_mm = (300, 400)
-        
+
         assert project.page_size_mm == (300, 400)
 
     def test_project_name_modification(self):
         """Test modifying project name"""
         project = Project(name="Initial Name")
         project.name = "New Name"
-        
+
         assert project.name == "New Name"
 
     def test_asset_manager_exists(self):
         """Test that project has an asset manager"""
         project = Project()
-        
-        assert hasattr(project, 'asset_manager')
+
+        assert hasattr(project, "asset_manager")
         assert project.asset_manager is not None
 
     def test_history_exists(self):
         """Test that project has a history manager"""
         project = Project()
-        
-        assert hasattr(project, 'history')
+
+        assert hasattr(project, "history")
         assert project.history is not None
 
     def test_pages_list_is_mutable(self):
         """Test that pages list can be directly modified"""
         project = Project()
         page = Page(layout=PageLayout(), page_number=1)
-        
+
         project.pages.append(page)
-        
+
         assert len(project.pages) == 1
         assert project.pages[0] is page
 
     def test_empty_project_has_no_pages(self):
         """Test that a new project has no pages"""
         project = Project()
-        
+
         assert len(project.pages) == 0
         assert project.pages == []
 
@@ -167,23 +167,17 @@ class TestProjectWithPages:
     def test_project_with_populated_pages(self, sample_image_data):
         """Test project with pages containing elements"""
         project = Project(name="Photo Album")
-        
+
         # Create pages with elements
         for i in range(3):
             layout = PageLayout()
-            img = ImageData(
-                image_path=f"image_{i}.jpg",
-                x=10 + i*10,
-                y=20 + i*10,
-                width=100,
-                height=100
-            )
+            img = ImageData(image_path=f"image_{i}.jpg", x=10 + i * 10, y=20 + i * 10, width=100, height=100)
             layout.add_element(img)
-            page = Page(layout=layout, page_number=i+1)
+            page = Page(layout=layout, page_number=i + 1)
             project.add_page(page)
-        
+
         assert len(project.pages) == 3
-        
+
         # Check each page has elements
         for i, page in enumerate(project.pages):
             assert len(page.layout.elements) == 1
@@ -192,18 +186,18 @@ class TestProjectWithPages:
     def test_reorder_pages(self):
         """Test reordering pages in project"""
         project = Project()
-        
+
         page1 = Page(layout=PageLayout(), page_number=1)
         page2 = Page(layout=PageLayout(), page_number=2)
         page3 = Page(layout=PageLayout(), page_number=3)
-        
+
         project.add_page(page1)
         project.add_page(page2)
         project.add_page(page3)
-        
+
         # Swap page 1 and page 3
         project.pages[0], project.pages[2] = project.pages[2], project.pages[0]
-        
+
         assert project.pages[0] is page3
         assert project.pages[1] is page2
         assert project.pages[2] is page1
@@ -211,43 +205,43 @@ class TestProjectWithPages:
     def test_clear_all_pages(self):
         """Test clearing all pages from project"""
         project = Project()
-        
+
         for i in range(5):
-            page = Page(layout=PageLayout(), page_number=i+1)
+            page = Page(layout=PageLayout(), page_number=i + 1)
             project.add_page(page)
-        
+
         # Clear all pages
         project.pages.clear()
-        
+
         assert len(project.pages) == 0
 
     def test_get_page_by_index(self):
         """Test accessing pages by index"""
         project = Project()
-        
+
         page1 = Page(layout=PageLayout(), page_number=1)
         page2 = Page(layout=PageLayout(), page_number=2)
-        
+
         project.add_page(page1)
         project.add_page(page2)
-        
+
         assert project.pages[0] is page1
         assert project.pages[1] is page2
 
     def test_insert_page_at_position(self):
         """Test inserting a page at a specific position"""
         project = Project()
-        
+
         page1 = Page(layout=PageLayout(), page_number=1)
         page2 = Page(layout=PageLayout(), page_number=2)
         page_new = Page(layout=PageLayout(), page_number=99)
-        
+
         project.add_page(page1)
         project.add_page(page2)
-        
+
         # Insert new page in the middle
         project.pages.insert(1, page_new)
-        
+
         assert len(project.pages) == 3
         assert project.pages[0] is page1
         assert project.pages[1] is page_new
diff --git a/tests/test_project_serialization.py b/tests/test_project_serialization.py
index 830982c..f31c6f6 100755
--- a/tests/test_project_serialization.py
+++ b/tests/test_project_serialization.py
@@ -39,9 +39,9 @@ def sample_project(temp_dir):
 def sample_image(temp_dir):
     """Create a sample image file for testing"""
     from PIL import Image
-    
+
     # Create a simple test image
-    img = Image.new('RGB', (100, 100), color='red')
+    img = Image.new("RGB", (100, 100), color="red")
     image_path = os.path.join(temp_dir, "test_image.jpg")
     img.save(image_path)
     return image_path
@@ -49,42 +49,41 @@ def sample_image(temp_dir):
 
 class TestBasicSerialization:
     """Tests for basic save/load functionality"""
-    
+
     def test_save_empty_project(self, sample_project, temp_dir):
         """Test saving an empty project to ZIP"""
         zip_path = os.path.join(temp_dir, "empty_project.ppz")
-        
+
         success, error = save_to_zip(sample_project, zip_path)
-        
+
         assert success is True
         assert error is None
         assert os.path.exists(zip_path)
-        assert zip_path.endswith('.ppz')
-    
+        assert zip_path.endswith(".ppz")
+
     def test_save_adds_ppz_extension(self, sample_project, temp_dir):
         """Test that .ppz extension is added automatically"""
         zip_path = os.path.join(temp_dir, "project")
-        
+
         success, error = save_to_zip(sample_project, zip_path)
-        
+
         assert success is True
-        expected_path = zip_path + '.ppz'
+        expected_path = zip_path + ".ppz"
         assert os.path.exists(expected_path)
-    
+
     def test_load_empty_project(self, sample_project, temp_dir):
         """Test loading an empty project from ZIP"""
         zip_path = os.path.join(temp_dir, "empty_project.ppz")
         save_to_zip(sample_project, zip_path)
-        
+
         loaded_project = load_from_zip(zip_path)
 
-        
         assert loaded_project is not None
         assert loaded_project.name == "Test Project"
         assert loaded_project.page_size_mm == (210, 297)
         assert loaded_project.working_dpi == 300
         assert len(loaded_project.pages) == 0
-    
+
     def test_load_nonexistent_file(self, temp_dir):
         """Test loading from a non-existent file"""
         zip_path = os.path.join(temp_dir, "nonexistent.ppz")
@@ -95,34 +94,34 @@ class TestBasicSerialization:
         except Exception as error:
             assert error is not None
             assert "not found" in str(error).lower()
-    
+
     def test_save_project_with_pages(self, sample_project, temp_dir):
         """Test saving a project with multiple pages"""
         # Add pages
         for i in range(3):
             layout = PageLayout()
-            page = Page(layout=layout, page_number=i+1)
+            page = Page(layout=layout, page_number=i + 1)
             sample_project.add_page(page)
-        
+
         zip_path = os.path.join(temp_dir, "project_with_pages.ppz")
         success, error = save_to_zip(sample_project, zip_path)
-        
+
         assert success is True
         assert os.path.exists(zip_path)
-    
+
     def test_load_project_with_pages(self, sample_project, temp_dir):
         """Test loading a project with multiple pages"""
         # Add pages
         for i in range(3):
             layout = PageLayout()
-            page = Page(layout=layout, page_number=i+1)
+            page = Page(layout=layout, page_number=i + 1)
             sample_project.add_page(page)
-        
+
         # Save and load
         zip_path = os.path.join(temp_dir, "project_with_pages.ppz")
         save_to_zip(sample_project, zip_path)
         loaded_project = load_from_zip(zip_path)
-        
+
         assert loaded_project is not None
         assert len(loaded_project.pages) == 3
         assert loaded_project.pages[0].page_number == 1
@@ -131,139 +130,139 @@ class TestBasicSerialization:
 
 class TestZipStructure:
     """Tests for ZIP file structure and content"""
-    
+
     def test_zip_contains_project_json(self, sample_project, temp_dir):
         """Test that ZIP contains project.json"""
         zip_path = os.path.join(temp_dir, "test.ppz")
         save_to_zip(sample_project, zip_path)
-        
-        with zipfile.ZipFile(zip_path, 'r') as zipf:
-            assert 'project.json' in zipf.namelist()
-    
+
+        with zipfile.ZipFile(zip_path, "r") as zipf:
+            assert "project.json" in zipf.namelist()
+
     def test_project_json_is_valid(self, sample_project, temp_dir):
         """Test that project.json contains valid JSON"""
         zip_path = os.path.join(temp_dir, "test.ppz")
         save_to_zip(sample_project, zip_path)
-        
-        with zipfile.ZipFile(zip_path, 'r') as zipf:
-            project_json = zipf.read('project.json').decode('utf-8')
+
+        with zipfile.ZipFile(zip_path, "r") as zipf:
+            project_json = zipf.read("project.json").decode("utf-8")
             data = json.loads(project_json)
-            
-            assert 'name' in data
-            assert 'serialization_version' in data
-            assert data['name'] == "Test Project"
-    
+
+            assert "name" in data
+            assert "serialization_version" in data
+            assert data["name"] == "Test Project"
+
     def test_version_in_serialized_data(self, sample_project, temp_dir):
         """Test that version information is included"""
         zip_path = os.path.join(temp_dir, "test.ppz")
         save_to_zip(sample_project, zip_path)
-        
-        with zipfile.ZipFile(zip_path, 'r') as zipf:
-            project_json = zipf.read('project.json').decode('utf-8')
+
+        with zipfile.ZipFile(zip_path, "r") as zipf:
+            project_json = zipf.read("project.json").decode("utf-8")
             data = json.loads(project_json)
-            
-            assert 'serialization_version' in data
-            assert data['serialization_version'] == "3.0"
+
+            assert "serialization_version" in data
+            assert data["serialization_version"] == "3.0"
 
 
 class TestAssetManagement:
     """Tests for asset bundling and management"""
-    
+
     def test_save_project_with_image(self, sample_project, sample_image, temp_dir):
         """Test saving a project with an image"""
         # Import image to project
         imported_path = sample_project.asset_manager.import_asset(sample_image)
-        
+
         # Create page with image
         layout = PageLayout()
         img_data = ImageData(image_path=imported_path, x=10, y=10, width=100, height=100)
         layout.add_element(img_data)
         page = Page(layout=layout, page_number=1)
         sample_project.add_page(page)
-        
+
         # Save
         zip_path = os.path.join(temp_dir, "project_with_image.ppz")
         success, error = save_to_zip(sample_project, zip_path)
-        
+
         assert success is True
         assert os.path.exists(zip_path)
-    
+
     def test_assets_folder_in_zip(self, sample_project, sample_image, temp_dir):
         """Test that assets folder is included in ZIP"""
         # Import image
         imported_path = sample_project.asset_manager.import_asset(sample_image)
-        
+
         # Create page with image
         layout = PageLayout()
         img_data = ImageData(image_path=imported_path, x=10, y=10, width=100, height=100)
         layout.add_element(img_data)
         page = Page(layout=layout, page_number=1)
         sample_project.add_page(page)
-        
+
         # Save
         zip_path = os.path.join(temp_dir, "project_with_image.ppz")
         save_to_zip(sample_project, zip_path)
-        
+
         # Check ZIP contents
-        with zipfile.ZipFile(zip_path, 'r') as zipf:
+        with zipfile.ZipFile(zip_path, "r") as zipf:
             names = zipf.namelist()
             # Should contain assets folder
-            asset_files = [n for n in names if n.startswith('assets/')]
+            asset_files = [n for n in names if n.startswith("assets/")]
             assert len(asset_files) > 0
-    
+
     def test_load_project_with_image(self, sample_project, sample_image, temp_dir):
         """Test loading a project with images"""
         # Import image
         imported_path = sample_project.asset_manager.import_asset(sample_image)
-        
+
         # Create page with image
         layout = PageLayout()
         img_data = ImageData(image_path=imported_path, x=10, y=10, width=100, height=100)
         layout.add_element(img_data)
         page = Page(layout=layout, page_number=1)
         sample_project.add_page(page)
-        
+
         # Save and load
         zip_path = os.path.join(temp_dir, "project_with_image.ppz")
         save_to_zip(sample_project, zip_path)
         loaded_project = load_from_zip(zip_path)
-        
+
         assert loaded_project is not None
         assert len(loaded_project.pages) == 1
         assert len(loaded_project.pages[0].layout.elements) == 1
-        
+
         # Verify image element
         img_element = loaded_project.pages[0].layout.elements[0]
         assert isinstance(img_element, ImageData)
         assert img_element.image_path != ""
-    
+
     def test_asset_reference_counts_preserved(self, sample_project, sample_image, temp_dir):
         """Test that asset reference counts are preserved"""
         # Import image
         imported_path = sample_project.asset_manager.import_asset(sample_image)
-        
+
         # Use image twice
         layout1 = PageLayout()
         img1 = ImageData(image_path=imported_path, x=10, y=10, width=100, height=100)
         layout1.add_element(img1)
         page1 = Page(layout=layout1, page_number=1)
         sample_project.add_page(page1)
-        
+
         layout2 = PageLayout()
         img2 = ImageData(image_path=imported_path, x=20, y=20, width=100, height=100)
         layout2.add_element(img2)
         page2 = Page(layout=layout2, page_number=2)
         sample_project.add_page(page2)
-        
+
         # Get relative path for reference count check
         rel_path = os.path.relpath(imported_path, sample_project.folder_path)
         original_ref_count = sample_project.asset_manager.get_reference_count(rel_path)
-        
+
         # Save and load
         zip_path = os.path.join(temp_dir, "project_refs.ppz")
         save_to_zip(sample_project, zip_path)
         loaded_project = load_from_zip(zip_path)
-        
+
         assert loaded_project is not None
         # Reference counts should be preserved
         # Note: The actual reference counting behavior depends on deserialize implementation
@@ -271,7 +270,7 @@ class TestAssetManagement:
 
 class TestPortability:
     """Tests for project portability across different locations"""
-    
+
     def test_load_to_different_directory(self, sample_project, sample_image, temp_dir):
         """Test loading project to a different directory"""
         # Import image and create page
@@ -281,23 +280,23 @@ class TestPortability:
         layout.add_element(img_data)
         page = Page(layout=layout, page_number=1)
         sample_project.add_page(page)
-        
+
         # Save
         zip_path = os.path.join(temp_dir, "portable_project.ppz")
         save_to_zip(sample_project, zip_path)
-        
+
         # Load to a different location
         new_location = os.path.join(temp_dir, "different_location")
         loaded_project = load_from_zip(zip_path, extract_to=new_location)
-        
+
         assert loaded_project is not None
         assert loaded_project.folder_path == new_location
         assert os.path.exists(new_location)
-        
+
         # Verify assets were extracted
         assets_folder = os.path.join(new_location, "assets")
         assert os.path.exists(assets_folder)
-    
+
     def test_relative_paths_work_after_move(self, sample_project, sample_image, temp_dir):
         """Test that relative paths still work after loading to different location"""
         # Import image
@@ -307,19 +306,19 @@ class TestPortability:
         layout.add_element(img_data)
         page = Page(layout=layout, page_number=1)
         sample_project.add_page(page)
-        
+
         # Save
         zip_path = os.path.join(temp_dir, "portable_project.ppz")
         save_to_zip(sample_project, zip_path)
-        
+
         # Load to different location
         new_location = os.path.join(temp_dir, "new_location")
         loaded_project = load_from_zip(zip_path, extract_to=new_location)
-        
+
         # Verify image path is accessible from new location
         img_element = loaded_project.pages[0].layout.elements[0]
         image_path = img_element.image_path
-        
+
         # Image path should exist
         # Note: May be absolute or relative depending on implementation
         if not os.path.isabs(image_path):
@@ -331,77 +330,73 @@ class TestPortability:
 
 class TestProjectInfo:
     """Tests for get_project_info utility function"""
-    
+
     def test_get_project_info(self, sample_project, temp_dir):
         """Test getting project info without loading"""
         # Add some pages
         for i in range(5):
             layout = PageLayout()
-            page = Page(layout=layout, page_number=i+1)
+            page = Page(layout=layout, page_number=i + 1)
             sample_project.add_page(page)
-        
+
         # Save
         zip_path = os.path.join(temp_dir, "info_test.ppz")
         save_to_zip(sample_project, zip_path)
-        
+
         # Get info
         info = get_project_info(zip_path)
-        
+
         assert info is not None
-        assert info['name'] == "Test Project"
-        assert info['page_count'] == 5
-        assert info['version'] == "3.0"
-        assert info['working_dpi'] == 300
-    
+        assert info["name"] == "Test Project"
+        assert info["page_count"] == 5
+        assert info["version"] == "3.0"
+        assert info["working_dpi"] == 300
+
     def test_get_info_invalid_zip(self, temp_dir):
         """Test getting info from invalid ZIP"""
         zip_path = os.path.join(temp_dir, "invalid.ppz")
-        
+
         info = get_project_info(zip_path)
-        
+
         assert info is None
 
 
 class TestEdgeCases:
     """Tests for edge cases and error handling"""
-    
+
     def test_save_to_invalid_path(self, sample_project):
         """Test saving to an invalid path"""
         invalid_path = "/nonexistent/directory/project.ppz"
-        
+
         success, error = save_to_zip(sample_project, invalid_path)
-        
+
         assert success is False
         assert error is not None
-    
+
     def test_load_corrupted_zip(self, temp_dir):
         """Test loading a corrupted ZIP file"""
         # Create a fake corrupted file
         corrupted_path = os.path.join(temp_dir, "corrupted.ppz")
-        with open(corrupted_path, 'w') as f:
+        with open(corrupted_path, "w") as f:
             f.write("This is not a ZIP file")
-        
+
         try:
 
-        
             loaded_project = load_from_zip(corrupted_path)
 
-        
             assert False, "Should have raised an exception"
 
-        
         except Exception as error:
 
-        
             assert error is not None
-    
+
     def test_load_zip_without_project_json(self, temp_dir):
         """Test loading a ZIP without project.json"""
         zip_path = os.path.join(temp_dir, "no_json.ppz")
 
         # Create ZIP without project.json
-        with zipfile.ZipFile(zip_path, 'w') as zipf:
-            zipf.writestr('dummy.txt', 'dummy content')
+        with zipfile.ZipFile(zip_path, "w") as zipf:
+            zipf.writestr("dummy.txt", "dummy content")
 
         try:
             loaded_project = load_from_zip(zip_path)
@@ -409,27 +404,24 @@ class TestEdgeCases:
         except Exception as error:
             assert error is not None
             assert "project.json not found" in str(error)
-    
+
     def test_project_with_text_elements(self, sample_project, temp_dir):
         """Test saving/loading project with text elements"""
         # Create page with text
         layout = PageLayout()
-        text = TextBoxData(
-            text_content="Hello World",
-            x=10, y=10, width=200, height=50
-        )
+        text = TextBoxData(text_content="Hello World", x=10, y=10, width=200, height=50)
         layout.add_element(text)
         page = Page(layout=layout, page_number=1)
         sample_project.add_page(page)
-        
+
         # Save and load
         zip_path = os.path.join(temp_dir, "with_text.ppz")
         save_to_zip(sample_project, zip_path)
         loaded_project = load_from_zip(zip_path)
-        
+
         assert loaded_project is not None
         assert len(loaded_project.pages) == 1
-        
+
         text_element = loaded_project.pages[0].layout.elements[0]
         assert isinstance(text_element, TextBoxData)
         assert text_element.text_content == "Hello World"
diff --git a/tests/test_project_serializer_full.py b/tests/test_project_serializer_full.py
new file mode 100644
index 0000000..2f3bdec
--- /dev/null
+++ b/tests/test_project_serializer_full.py
@@ -0,0 +1,432 @@
+"""
+Comprehensive tests for project_serializer module
+"""
+
+import pytest
+import os
+import json
+import zipfile
+import tempfile
+import shutil
+from pathlib import Path
+from unittest.mock import Mock, patch, MagicMock
+
+from pyPhotoAlbum.project_serializer import (
+    save_to_zip,
+    load_from_zip,
+    get_project_info,
+    _normalize_asset_paths,
+    _import_external_images,
+    SERIALIZATION_VERSION,
+)
+from pyPhotoAlbum.project import Project
+from pyPhotoAlbum.models import ImageData
+
+
+class TestSaveToZip:
+    """Tests for save_to_zip function"""
+
+    def test_save_to_zip_basic(self, tmp_path):
+        """Test basic project saving to zip"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        project = Project(name="TestProject", folder_path=str(project_folder))
+
+        zip_path = str(tmp_path / "test_project.ppz")
+        success, error = save_to_zip(project, zip_path)
+
+        assert success is True
+        assert error is None
+        assert os.path.exists(zip_path)
+
+    def test_save_to_zip_adds_extension(self, tmp_path):
+        """Test that .ppz extension is added if missing"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        project = Project(name="TestProject", folder_path=str(project_folder))
+
+        zip_path = str(tmp_path / "test_project")  # No extension
+        success, error = save_to_zip(project, zip_path)
+
+        assert success is True
+        assert os.path.exists(zip_path + ".ppz")
+
+    def test_save_to_zip_includes_project_json(self, tmp_path):
+        """Test that saved zip contains project.json"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        project = Project(name="TestProject", folder_path=str(project_folder))
+
+        zip_path = str(tmp_path / "test_project.ppz")
+        save_to_zip(project, zip_path)
+
+        with zipfile.ZipFile(zip_path, "r") as zipf:
+            assert "project.json" in zipf.namelist()
+
+            project_data = json.loads(zipf.read("project.json"))
+            assert project_data["name"] == "TestProject"
+            assert "data_version" in project_data
+
+    def test_save_to_zip_includes_assets(self, tmp_path):
+        """Test that saved zip includes asset files"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        # Create a dummy asset file
+        asset_file = assets_folder / "image.jpg"
+        asset_file.write_bytes(b"fake image data")
+
+        project = Project(name="TestProject", folder_path=str(project_folder))
+
+        zip_path = str(tmp_path / "test_project.ppz")
+        save_to_zip(project, zip_path)
+
+        with zipfile.ZipFile(zip_path, "r") as zipf:
+            assert "assets/image.jpg" in zipf.namelist()
+
+    def test_save_to_zip_handles_error(self, tmp_path):
+        """Test error handling during save"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        project = Project(name="TestProject", folder_path=str(project_folder))
+
+        # Try to save to an invalid path
+        zip_path = "/nonexistent/directory/test.ppz"
+        success, error = save_to_zip(project, zip_path)
+
+        assert success is False
+        assert error is not None
+        assert "Error saving" in error
+
+
+class TestLoadFromZip:
+    """Tests for load_from_zip function"""
+
+    def test_load_from_zip_basic(self, tmp_path):
+        """Test basic project loading from zip"""
+        # First create a valid project zip
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        project = Project(name="LoadTest", folder_path=str(project_folder))
+        zip_path = str(tmp_path / "test_project.ppz")
+        save_to_zip(project, zip_path)
+
+        # Now load it
+        extract_to = str(tmp_path / "extracted")
+        loaded_project = load_from_zip(zip_path, extract_to)
+
+        assert loaded_project.name == "LoadTest"
+        assert loaded_project.folder_path == extract_to
+
+    def test_load_from_zip_creates_temp_dir(self, tmp_path):
+        """Test that loading creates a temp directory when none specified"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        project = Project(name="TempTest", folder_path=str(project_folder))
+        zip_path = str(tmp_path / "test_project.ppz")
+        save_to_zip(project, zip_path)
+
+        # Load without specifying extraction directory
+        loaded_project = load_from_zip(zip_path)
+
+        assert loaded_project.name == "TempTest"
+        assert loaded_project.folder_path is not None
+        assert os.path.exists(loaded_project.folder_path)
+
+        # Should have a _temp_dir attribute
+        assert hasattr(loaded_project, "_temp_dir")
+
+    def test_load_from_zip_file_not_found(self, tmp_path):
+        """Test loading from nonexistent file"""
+        with pytest.raises(FileNotFoundError):
+            load_from_zip(str(tmp_path / "nonexistent.ppz"))
+
+    def test_load_from_zip_invalid_zip(self, tmp_path):
+        """Test loading from invalid zip file"""
+        invalid_file = tmp_path / "invalid.ppz"
+        invalid_file.write_text("not a zip file")
+
+        with pytest.raises(Exception):
+            load_from_zip(str(invalid_file))
+
+    def test_load_from_zip_missing_project_json(self, tmp_path):
+        """Test loading from zip without project.json"""
+        zip_path = tmp_path / "no_project.ppz"
+
+        # Create zip without project.json
+        with zipfile.ZipFile(str(zip_path), "w") as zipf:
+            zipf.writestr("other_file.txt", "some content")
+
+        with pytest.raises(ValueError) as exc_info:
+            load_from_zip(str(zip_path))
+
+        assert "project.json not found" in str(exc_info.value)
+
+
+class TestGetProjectInfo:
+    """Tests for get_project_info function"""
+
+    def test_get_project_info_basic(self, tmp_path):
+        """Test getting project info from zip"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        project = Project(name="InfoTest", folder_path=str(project_folder))
+        zip_path = str(tmp_path / "test_project.ppz")
+        save_to_zip(project, zip_path)
+
+        info = get_project_info(zip_path)
+
+        assert info is not None
+        assert info["name"] == "InfoTest"
+        assert "version" in info
+        assert "page_count" in info
+        assert "page_size_mm" in info
+        assert "working_dpi" in info
+
+    def test_get_project_info_invalid_file(self, tmp_path):
+        """Test getting info from invalid file"""
+        invalid_file = tmp_path / "invalid.ppz"
+        invalid_file.write_text("not a zip")
+
+        info = get_project_info(str(invalid_file))
+
+        assert info is None
+
+    def test_get_project_info_nonexistent_file(self, tmp_path):
+        """Test getting info from nonexistent file"""
+        info = get_project_info(str(tmp_path / "nonexistent.ppz"))
+
+        assert info is None
+
+
+class TestNormalizeAssetPaths:
+    """Tests for _normalize_asset_paths function"""
+
+    def test_normalize_relative_path_unchanged(self, tmp_path):
+        """Test that simple relative paths are unchanged"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        project = Project(name="Test", folder_path=str(project_folder))
+
+        # Add a page with an image that has a simple relative path
+        from pyPhotoAlbum.page_layout import PageLayout
+
+        page_mock = Mock()
+        layout = PageLayout(width=210, height=297)
+        img = ImageData(image_path="assets/image.jpg")
+        layout.add_element(img)
+        page_mock.layout = layout
+        project.pages = [page_mock]
+
+        _normalize_asset_paths(project, str(project_folder))
+
+        # Path should be unchanged
+        assert img.image_path == "assets/image.jpg"
+
+    def test_normalize_absolute_path(self, tmp_path):
+        """Test that absolute paths are normalized"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        project = Project(name="Test", folder_path=str(project_folder))
+
+        from pyPhotoAlbum.page_layout import PageLayout
+
+        page_mock = Mock()
+        layout = PageLayout(width=210, height=297)
+        # Use a path that contains /assets/ pattern
+        abs_path = str(project_folder / "assets" / "image.jpg")
+        img = ImageData(image_path=abs_path)
+        layout.add_element(img)
+        page_mock.layout = layout
+        project.pages = [page_mock]
+
+        _normalize_asset_paths(project, str(project_folder))
+
+        # Path should be normalized to relative
+        assert img.image_path == "assets/image.jpg"
+
+    def test_normalize_legacy_path(self, tmp_path):
+        """Test normalizing legacy project path format"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        project = Project(name="Test", folder_path=str(project_folder))
+
+        from pyPhotoAlbum.page_layout import PageLayout
+
+        page_mock = Mock()
+        layout = PageLayout(width=210, height=297)
+        # Legacy path format
+        img = ImageData(image_path="./projects/old_project/assets/image.jpg")
+        layout.add_element(img)
+        page_mock.layout = layout
+        project.pages = [page_mock]
+
+        _normalize_asset_paths(project, str(project_folder))
+
+        # Should extract just the assets/filename part
+        assert img.image_path == "assets/image.jpg"
+
+
+class TestImportExternalImages:
+    """Tests for _import_external_images function"""
+
+    def test_import_external_images_no_external(self, tmp_path):
+        """Test with no external images"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        project = Project(name="Test", folder_path=str(project_folder))
+
+        from pyPhotoAlbum.page_layout import PageLayout
+
+        page_mock = Mock()
+        layout = PageLayout(width=210, height=297)
+        img = ImageData(image_path="assets/existing.jpg")
+        layout.add_element(img)
+        page_mock.layout = layout
+        project.pages = [page_mock]
+
+        # Should not raise and not change path
+        _import_external_images(project)
+
+        assert img.image_path == "assets/existing.jpg"
+
+
+class TestRoundTrip:
+    """Test save and load roundtrip"""
+
+    def test_roundtrip_basic(self, tmp_path):
+        """Test saving and loading a project"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        original = Project(name="RoundTrip", folder_path=str(project_folder))
+        original.working_dpi = 150
+
+        zip_path = str(tmp_path / "roundtrip.ppz")
+        success, _ = save_to_zip(original, zip_path)
+        assert success
+
+        extract_to = str(tmp_path / "extracted")
+        loaded = load_from_zip(zip_path, extract_to)
+
+        assert loaded.name == original.name
+        assert loaded.working_dpi == original.working_dpi
+
+    def test_roundtrip_with_pages(self, tmp_path):
+        """Test roundtrip with pages"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        original = Project(name="WithPages", folder_path=str(project_folder))
+        # Project starts with 1 page, add more using create_page
+        from pyPhotoAlbum.project import Page
+        from pyPhotoAlbum.page_layout import PageLayout
+
+        page2 = Page(PageLayout(width=210, height=297))
+        page3 = Page(PageLayout(width=210, height=297))
+        original.add_page(page2)
+        original.add_page(page3)
+
+        zip_path = str(tmp_path / "pages.ppz")
+        save_to_zip(original, zip_path)
+
+        extract_to = str(tmp_path / "extracted")
+        loaded = load_from_zip(zip_path, extract_to)
+
+        # Pages are preserved (Project might not start with a default page)
+        assert len(loaded.pages) >= 2
+
+    def test_roundtrip_with_elements(self, tmp_path, temp_image_file):
+        """Test roundtrip with elements on page"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        # Copy temp image to assets
+        shutil.copy(temp_image_file, assets_folder / "test.jpg")
+
+        original = Project(name="WithElements", folder_path=str(project_folder))
+
+        # Add element to first page (project starts with at least 1 page)
+        img = ImageData(image_path="assets/test.jpg", x=50, y=50, width=100, height=100)
+        # Check if there's a default page, add one if needed
+        if not original.pages:
+            from pyPhotoAlbum.project import Page
+            from pyPhotoAlbum.page_layout import PageLayout
+
+            original.add_page(Page(PageLayout(width=210, height=297)))
+        original.pages[0].layout.add_element(img)
+
+        zip_path = str(tmp_path / "elements.ppz")
+        save_to_zip(original, zip_path)
+
+        extract_to = str(tmp_path / "extracted")
+        loaded = load_from_zip(zip_path, extract_to)
+
+        assert len(loaded.pages) >= 1
+        assert len(loaded.pages[0].layout.elements) >= 1
+        loaded_elem = loaded.pages[0].layout.elements[0]
+        assert loaded_elem.position == (50.0, 50.0)
+        assert loaded_elem.size == (100.0, 100.0)
+
+
+class TestVersionCompatibility:
+    """Tests for version handling"""
+
+    def test_version_included_in_save(self, tmp_path):
+        """Test that version is included when saving"""
+        project_folder = tmp_path / "project"
+        project_folder.mkdir()
+        assets_folder = project_folder / "assets"
+        assets_folder.mkdir()
+
+        project = Project(name="Version", folder_path=str(project_folder))
+        zip_path = str(tmp_path / "version.ppz")
+        save_to_zip(project, zip_path)
+
+        with zipfile.ZipFile(zip_path, "r") as zipf:
+            data = json.loads(zipf.read("project.json"))
+
+        # Should have both legacy and new version fields
+        assert "serialization_version" in data
+        assert "data_version" in data
diff --git a/tests/test_ribbon_builder.py b/tests/test_ribbon_builder.py
new file mode 100644
index 0000000..a945371
--- /dev/null
+++ b/tests/test_ribbon_builder.py
@@ -0,0 +1,634 @@
+"""
+Tests for ribbon_builder module
+"""
+
+import pytest
+from io import StringIO
+from unittest.mock import Mock, patch
+
+from pyPhotoAlbum.ribbon_builder import (
+    build_ribbon_config,
+    get_keyboard_shortcuts,
+    validate_ribbon_config,
+    print_ribbon_summary,
+)
+
+
+class TestBuildRibbonConfig:
+    """Tests for build_ribbon_config function"""
+
+    def test_empty_class(self):
+        """Test with a class that has no ribbon actions"""
+
+        class EmptyClass:
+            pass
+
+        config = build_ribbon_config(EmptyClass)
+        assert config == {}
+
+    def test_single_action(self):
+        """Test with a class that has one ribbon action"""
+
+        class SingleAction:
+            def my_action(self):
+                pass
+
+            my_action._ribbon_action = {
+                "tab": "Home",
+                "group": "File",
+                "label": "My Action",
+                "action": "my_action",
+                "tooltip": "Does something",
+            }
+
+        config = build_ribbon_config(SingleAction)
+
+        assert "Home" in config
+        assert len(config["Home"]["groups"]) == 1
+        assert config["Home"]["groups"][0]["name"] == "File"
+        assert len(config["Home"]["groups"][0]["actions"]) == 1
+        assert config["Home"]["groups"][0]["actions"][0]["label"] == "My Action"
+
+    def test_multiple_actions_same_group(self):
+        """Test with multiple actions in the same group"""
+
+        class MultiAction:
+            def action1(self):
+                pass
+
+            action1._ribbon_action = {
+                "tab": "Home",
+                "group": "Edit",
+                "label": "Action 1",
+                "action": "action1",
+                "tooltip": "First action",
+            }
+
+            def action2(self):
+                pass
+
+            action2._ribbon_action = {
+                "tab": "Home",
+                "group": "Edit",
+                "label": "Action 2",
+                "action": "action2",
+                "tooltip": "Second action",
+            }
+
+        config = build_ribbon_config(MultiAction)
+
+        assert "Home" in config
+        assert len(config["Home"]["groups"]) == 1
+        assert config["Home"]["groups"][0]["name"] == "Edit"
+        assert len(config["Home"]["groups"][0]["actions"]) == 2
+
+    def test_multiple_groups(self):
+        """Test with actions in different groups"""
+
+        class MultiGroup:
+            def action1(self):
+                pass
+
+            action1._ribbon_action = {
+                "tab": "Home",
+                "group": "File",
+                "label": "File Action",
+                "action": "action1",
+                "tooltip": "File stuff",
+            }
+
+            def action2(self):
+                pass
+
+            action2._ribbon_action = {
+                "tab": "Home",
+                "group": "Edit",
+                "label": "Edit Action",
+                "action": "action2",
+                "tooltip": "Edit stuff",
+            }
+
+        config = build_ribbon_config(MultiGroup)
+
+        assert "Home" in config
+        assert len(config["Home"]["groups"]) == 2
+        group_names = [g["name"] for g in config["Home"]["groups"]]
+        assert "File" in group_names
+        assert "Edit" in group_names
+
+    def test_multiple_tabs(self):
+        """Test with actions in different tabs"""
+
+        class MultiTab:
+            def action1(self):
+                pass
+
+            action1._ribbon_action = {
+                "tab": "Home",
+                "group": "File",
+                "label": "Home Action",
+                "action": "action1",
+                "tooltip": "Home stuff",
+            }
+
+            def action2(self):
+                pass
+
+            action2._ribbon_action = {
+                "tab": "View",
+                "group": "Zoom",
+                "label": "View Action",
+                "action": "action2",
+                "tooltip": "View stuff",
+            }
+
+        config = build_ribbon_config(MultiTab)
+
+        assert "Home" in config
+        assert "View" in config
+
+    def test_tab_ordering(self):
+        """Test that tabs are ordered correctly"""
+
+        class OrderedTabs:
+            def action1(self):
+                pass
+
+            action1._ribbon_action = {
+                "tab": "Export",
+                "group": "Export",
+                "label": "Export",
+                "action": "action1",
+                "tooltip": "Export",
+            }
+
+            def action2(self):
+                pass
+
+            action2._ribbon_action = {
+                "tab": "Home",
+                "group": "File",
+                "label": "Home",
+                "action": "action2",
+                "tooltip": "Home",
+            }
+
+            def action3(self):
+                pass
+
+            action3._ribbon_action = {
+                "tab": "View",
+                "group": "Zoom",
+                "label": "View",
+                "action": "action3",
+                "tooltip": "View",
+            }
+
+        config = build_ribbon_config(OrderedTabs)
+        tab_names = list(config.keys())
+
+        # Home should come before View, View before Export
+        assert tab_names.index("Home") < tab_names.index("View")
+        assert tab_names.index("View") < tab_names.index("Export")
+
+    def test_action_with_optional_fields(self):
+        """Test action with optional icon and shortcut"""
+
+        class WithOptional:
+            def action(self):
+                pass
+
+            action._ribbon_action = {
+                "tab": "Home",
+                "group": "File",
+                "label": "Save",
+                "action": "save",
+                "tooltip": "Save project",
+                "icon": "save.png",
+                "shortcut": "Ctrl+S",
+            }
+
+        config = build_ribbon_config(WithOptional)
+
+        action = config["Home"]["groups"][0]["actions"][0]
+        assert action["icon"] == "save.png"
+        assert action["shortcut"] == "Ctrl+S"
+
+    def test_action_without_optional_fields(self):
+        """Test action without optional icon and shortcut"""
+
+        class WithoutOptional:
+            def action(self):
+                pass
+
+            action._ribbon_action = {
+                "tab": "Home",
+                "group": "File",
+                "label": "Action",
+                "action": "action",
+                "tooltip": "Does stuff",
+            }
+
+        config = build_ribbon_config(WithoutOptional)
+
+        action = config["Home"]["groups"][0]["actions"][0]
+        assert action.get("icon") is None
+        assert action.get("shortcut") is None
+
+    def test_custom_tab_not_in_order(self):
+        """Test custom tab not in predefined order"""
+
+        class CustomTab:
+            def action(self):
+                pass
+
+            action._ribbon_action = {
+                "tab": "CustomTab",
+                "group": "CustomGroup",
+                "label": "Custom",
+                "action": "action",
+                "tooltip": "Custom action",
+            }
+
+        config = build_ribbon_config(CustomTab)
+
+        assert "CustomTab" in config
+
+    def test_inherited_actions(self):
+        """Test that actions from parent classes are included"""
+
+        class BaseClass:
+            def base_action(self):
+                pass
+
+            base_action._ribbon_action = {
+                "tab": "Home",
+                "group": "File",
+                "label": "Base Action",
+                "action": "base_action",
+                "tooltip": "From base",
+            }
+
+        class DerivedClass(BaseClass):
+            def derived_action(self):
+                pass
+
+            derived_action._ribbon_action = {
+                "tab": "Home",
+                "group": "Edit",
+                "label": "Derived Action",
+                "action": "derived_action",
+                "tooltip": "From derived",
+            }
+
+        config = build_ribbon_config(DerivedClass)
+
+        # Should have both actions
+        all_actions = []
+        for group in config["Home"]["groups"]:
+            all_actions.extend(group["actions"])
+
+        action_names = [a["action"] for a in all_actions]
+        assert "base_action" in action_names
+        assert "derived_action" in action_names
+
+
+class TestGetKeyboardShortcuts:
+    """Tests for get_keyboard_shortcuts function"""
+
+    def test_empty_class(self):
+        """Test with a class that has no shortcuts"""
+
+        class NoShortcuts:
+            pass
+
+        shortcuts = get_keyboard_shortcuts(NoShortcuts)
+        assert shortcuts == {}
+
+    def test_single_shortcut(self):
+        """Test with a single shortcut"""
+
+        class SingleShortcut:
+            def save(self):
+                pass
+
+            save._ribbon_action = {
+                "tab": "Home",
+                "group": "File",
+                "label": "Save",
+                "action": "save",
+                "tooltip": "Save",
+                "shortcut": "Ctrl+S",
+            }
+
+        shortcuts = get_keyboard_shortcuts(SingleShortcut)
+
+        assert "Ctrl+S" in shortcuts
+        assert shortcuts["Ctrl+S"] == "save"
+
+    def test_multiple_shortcuts(self):
+        """Test with multiple shortcuts"""
+
+        class MultiShortcut:
+            def save(self):
+                pass
+
+            save._ribbon_action = {
+                "tab": "Home",
+                "group": "File",
+                "label": "Save",
+                "action": "save",
+                "tooltip": "Save",
+                "shortcut": "Ctrl+S",
+            }
+
+            def undo(self):
+                pass
+
+            undo._ribbon_action = {
+                "tab": "Home",
+                "group": "Edit",
+                "label": "Undo",
+                "action": "undo",
+                "tooltip": "Undo",
+                "shortcut": "Ctrl+Z",
+            }
+
+        shortcuts = get_keyboard_shortcuts(MultiShortcut)
+
+        assert len(shortcuts) == 2
+        assert shortcuts["Ctrl+S"] == "save"
+        assert shortcuts["Ctrl+Z"] == "undo"
+
+    def test_action_without_shortcut_ignored(self):
+        """Test that actions without shortcuts are not included"""
+
+        class MixedShortcuts:
+            def with_shortcut(self):
+                pass
+
+            with_shortcut._ribbon_action = {
+                "tab": "Home",
+                "group": "File",
+                "label": "With",
+                "action": "with_shortcut",
+                "tooltip": "Has shortcut",
+                "shortcut": "Ctrl+W",
+            }
+
+            def without_shortcut(self):
+                pass
+
+            without_shortcut._ribbon_action = {
+                "tab": "Home",
+                "group": "File",
+                "label": "Without",
+                "action": "without_shortcut",
+                "tooltip": "No shortcut",
+            }
+
+        shortcuts = get_keyboard_shortcuts(MixedShortcuts)
+
+        assert len(shortcuts) == 1
+        assert "Ctrl+W" in shortcuts
+
+
+class TestValidateRibbonConfig:
+    """Tests for validate_ribbon_config function"""
+
+    def test_valid_config(self):
+        """Test with a valid configuration"""
+        config = {
+            "Home": {
+                "groups": [
+                    {
+                        "name": "File",
+                        "actions": [
+                            {
+                                "label": "Save",
+                                "action": "save",
+                                "tooltip": "Save project",
+                            }
+                        ],
+                    }
+                ]
+            }
+        }
+
+        errors = validate_ribbon_config(config)
+        assert errors == []
+
+    def test_empty_config(self):
+        """Test with empty config"""
+        errors = validate_ribbon_config({})
+        assert errors == []
+
+    def test_config_not_dict(self):
+        """Test with non-dict config"""
+        errors = validate_ribbon_config("not a dict")
+        assert len(errors) == 1
+        assert "must be a dictionary" in errors[0]
+
+    def test_tab_data_not_dict(self):
+        """Test with tab data that is not a dict"""
+        config = {"Home": "not a dict"}
+
+        errors = validate_ribbon_config(config)
+        assert len(errors) == 1
+        assert "Tab 'Home' data must be a dictionary" in errors[0]
+
+    def test_missing_groups_key(self):
+        """Test with missing 'groups' key"""
+        config = {"Home": {"other_key": []}}
+
+        errors = validate_ribbon_config(config)
+        assert len(errors) == 1
+        assert "missing 'groups' key" in errors[0]
+
+    def test_groups_not_list(self):
+        """Test with groups that is not a list"""
+        config = {"Home": {"groups": "not a list"}}
+
+        errors = validate_ribbon_config(config)
+        assert len(errors) == 1
+        assert "groups must be a list" in errors[0]
+
+    def test_group_not_dict(self):
+        """Test with group that is not a dict"""
+        config = {"Home": {"groups": ["not a dict"]}}
+
+        errors = validate_ribbon_config(config)
+        assert len(errors) == 1
+        assert "group 0 must be a dictionary" in errors[0]
+
+    def test_group_missing_name(self):
+        """Test with group missing name"""
+        config = {"Home": {"groups": [{"actions": []}]}}
+
+        errors = validate_ribbon_config(config)
+        assert any("missing 'name'" in e for e in errors)
+
+    def test_group_missing_actions(self):
+        """Test with group missing actions"""
+        config = {"Home": {"groups": [{"name": "File"}]}}
+
+        errors = validate_ribbon_config(config)
+        assert any("missing 'actions'" in e for e in errors)
+
+    def test_actions_not_list(self):
+        """Test with actions that is not a list"""
+        config = {"Home": {"groups": [{"name": "File", "actions": "not a list"}]}}
+
+        errors = validate_ribbon_config(config)
+        assert any("actions must be a list" in e for e in errors)
+
+    def test_action_not_dict(self):
+        """Test with action that is not a dict"""
+        config = {"Home": {"groups": [{"name": "File", "actions": ["not a dict"]}]}}
+
+        errors = validate_ribbon_config(config)
+        assert any("action 0 must be a dictionary" in e for e in errors)
+
+    def test_action_missing_required_keys(self):
+        """Test with action missing required keys"""
+        config = {
+            "Home": {
+                "groups": [
+                    {
+                        "name": "File",
+                        "actions": [
+                            {
+                                "label": "Save"
+                                # missing 'action' and 'tooltip'
+                            }
+                        ],
+                    }
+                ]
+            }
+        }
+
+        errors = validate_ribbon_config(config)
+        assert any("missing 'action'" in e for e in errors)
+        assert any("missing 'tooltip'" in e for e in errors)
+
+    def test_multiple_errors(self):
+        """Test that multiple errors are collected"""
+        config = {
+            "Tab1": {"groups": [{"name": "Group1", "actions": [{"label": "A"}]}]},  # missing action and tooltip
+            "Tab2": {"groups": "not a list"},
+        }
+
+        errors = validate_ribbon_config(config)
+        assert len(errors) >= 3  # At least: missing action, missing tooltip, groups not list
+
+
+class TestPrintRibbonSummary:
+    """Tests for print_ribbon_summary function"""
+
+    def test_print_empty_config(self):
+        """Test printing empty config"""
+        config = {}
+
+        with patch("sys.stdout", new_callable=StringIO) as mock_stdout:
+            print_ribbon_summary(config)
+            output = mock_stdout.getvalue()
+
+        assert "Total Tabs: 0" in output
+        assert "Total Groups: 0" in output
+        assert "Total Actions: 0" in output
+
+    def test_print_single_tab(self):
+        """Test printing single tab config"""
+        config = {
+            "Home": {
+                "groups": [
+                    {
+                        "name": "File",
+                        "actions": [
+                            {
+                                "label": "Save",
+                                "action": "save",
+                                "tooltip": "Save",
+                            }
+                        ],
+                    }
+                ]
+            }
+        }
+
+        with patch("sys.stdout", new_callable=StringIO) as mock_stdout:
+            print_ribbon_summary(config)
+            output = mock_stdout.getvalue()
+
+        assert "Total Tabs: 1" in output
+        assert "Total Groups: 1" in output
+        assert "Total Actions: 1" in output
+        assert "Home" in output
+        assert "File" in output
+        assert "Save" in output
+
+    def test_print_with_shortcuts(self):
+        """Test printing actions with shortcuts"""
+        config = {
+            "Home": {
+                "groups": [
+                    {
+                        "name": "File",
+                        "actions": [
+                            {
+                                "label": "Save",
+                                "action": "save",
+                                "tooltip": "Save",
+                                "shortcut": "Ctrl+S",
+                            }
+                        ],
+                    }
+                ]
+            }
+        }
+
+        with patch("sys.stdout", new_callable=StringIO) as mock_stdout:
+            print_ribbon_summary(config)
+            output = mock_stdout.getvalue()
+
+        assert "(Ctrl+S)" in output
+
+    def test_print_multiple_tabs_and_groups(self):
+        """Test printing config with multiple tabs and groups"""
+        config = {
+            "Home": {
+                "groups": [
+                    {
+                        "name": "File",
+                        "actions": [
+                            {"label": "New", "action": "new", "tooltip": "New"},
+                            {"label": "Open", "action": "open", "tooltip": "Open"},
+                        ],
+                    },
+                    {
+                        "name": "Edit",
+                        "actions": [
+                            {"label": "Undo", "action": "undo", "tooltip": "Undo"},
+                        ],
+                    },
+                ]
+            },
+            "View": {
+                "groups": [
+                    {
+                        "name": "Zoom",
+                        "actions": [
+                            {"label": "Zoom In", "action": "zoom_in", "tooltip": "Zoom In"},
+                        ],
+                    }
+                ]
+            },
+        }
+
+        with patch("sys.stdout", new_callable=StringIO) as mock_stdout:
+            print_ribbon_summary(config)
+            output = mock_stdout.getvalue()
+
+        assert "Total Tabs: 2" in output
+        assert "Total Groups: 3" in output
+        assert "Total Actions: 4" in output
diff --git a/tests/test_ribbon_widget.py b/tests/test_ribbon_widget.py
new file mode 100644
index 0000000..cc53609
--- /dev/null
+++ b/tests/test_ribbon_widget.py
@@ -0,0 +1,402 @@
+"""
+Tests for ribbon_widget module
+"""
+
+import pytest
+from unittest.mock import Mock, MagicMock, patch
+
+
+class TestRibbonWidgetInit:
+    """Tests for RibbonWidget initialization"""
+
+    def test_init_with_custom_config(self, qtbot):
+        """Test initialization with custom ribbon config"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+
+        mock_main_window = Mock()
+        config = {
+            "File": {
+                "groups": [
+                    {"name": "Project", "actions": [{"label": "New", "action": "new_project", "tooltip": "Create new"}]}
+                ]
+            }
+        }
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        assert widget.main_window == mock_main_window
+        assert widget.ribbon_config == config
+        assert widget.buttons_per_row == 4  # default
+
+    def test_init_with_custom_buttons_per_row(self, qtbot):
+        """Test initialization with custom buttons_per_row"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+
+        mock_main_window = Mock()
+        config = {"Test": {"groups": []}}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config, buttons_per_row=6)
+        qtbot.addWidget(widget)
+
+        assert widget.buttons_per_row == 6
+
+    def test_init_creates_tab_widget(self, qtbot):
+        """Test that initialization creates a tab widget"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+
+        mock_main_window = Mock()
+        config = {"Tab1": {"groups": []}}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        assert widget.tab_widget is not None
+        assert widget.tab_widget.count() == 1
+
+
+class TestBuildRibbon:
+    """Tests for _build_ribbon method"""
+
+    def test_build_ribbon_creates_tabs(self, qtbot):
+        """Test that _build_ribbon creates tabs from config"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+
+        mock_main_window = Mock()
+        config = {"File": {"groups": []}, "Edit": {"groups": []}, "View": {"groups": []}}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        assert widget.tab_widget.count() == 3
+        # Tab names should be present
+        tab_names = [widget.tab_widget.tabText(i) for i in range(widget.tab_widget.count())]
+        assert "File" in tab_names
+        assert "Edit" in tab_names
+        assert "View" in tab_names
+
+    def test_build_ribbon_empty_config(self, qtbot):
+        """Test _build_ribbon with empty config"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+
+        mock_main_window = Mock()
+        config = {}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        assert widget.tab_widget.count() == 0
+
+
+class TestCreateTab:
+    """Tests for _create_tab method"""
+
+    def test_create_tab_with_groups(self, qtbot):
+        """Test tab creation with groups"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+
+        mock_main_window = Mock()
+        config = {"Test": {"groups": [{"name": "Group1", "actions": []}, {"name": "Group2", "actions": []}]}}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        # Get the tab widget content
+        tab_content = widget.tab_widget.widget(0)
+        assert tab_content is not None
+
+    def test_create_tab_empty_groups(self, qtbot):
+        """Test tab creation with no groups"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+
+        mock_main_window = Mock()
+        config = {"Test": {"groups": []}}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        tab_content = widget.tab_widget.widget(0)
+        assert tab_content is not None
+
+
+class TestCreateGroup:
+    """Tests for _create_group method"""
+
+    def test_create_group_with_actions(self, qtbot):
+        """Test group creation with action buttons"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+        from PyQt6.QtWidgets import QPushButton
+
+        mock_main_window = Mock()
+        config = {
+            "Test": {
+                "groups": [
+                    {
+                        "name": "Actions",
+                        "actions": [
+                            {"label": "Action1", "action": "do_action1"},
+                            {"label": "Action2", "action": "do_action2"},
+                        ],
+                    }
+                ]
+            }
+        }
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        tab_content = widget.tab_widget.widget(0)
+        # Find buttons in the tab
+        buttons = tab_content.findChildren(QPushButton)
+        assert len(buttons) == 2
+
+        button_labels = [btn.text() for btn in buttons]
+        assert "Action1" in button_labels
+        assert "Action2" in button_labels
+
+    def test_create_group_respects_buttons_per_row(self, qtbot):
+        """Test that group respects buttons_per_row from config"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+        from PyQt6.QtWidgets import QPushButton
+
+        mock_main_window = Mock()
+        config = {
+            "Test": {
+                "groups": [
+                    {
+                        "name": "Grid",
+                        "buttons_per_row": 2,
+                        "actions": [
+                            {"label": "A", "action": "a"},
+                            {"label": "B", "action": "b"},
+                            {"label": "C", "action": "c"},
+                            {"label": "D", "action": "d"},
+                        ],
+                    }
+                ]
+            }
+        }
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        tab_content = widget.tab_widget.widget(0)
+        buttons = tab_content.findChildren(QPushButton)
+        assert len(buttons) == 4
+
+
+class TestCreateActionButton:
+    """Tests for _create_action_button method"""
+
+    def test_button_has_correct_label(self, qtbot):
+        """Test that button has correct label"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+        from PyQt6.QtWidgets import QPushButton
+
+        mock_main_window = Mock()
+        config = {"Test": {"groups": [{"name": "Test", "actions": [{"label": "My Button", "action": "my_action"}]}]}}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        buttons = widget.tab_widget.widget(0).findChildren(QPushButton)
+        assert len(buttons) == 1
+        assert buttons[0].text() == "My Button"
+
+    def test_button_has_tooltip(self, qtbot):
+        """Test that button has correct tooltip"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+        from PyQt6.QtWidgets import QPushButton
+
+        mock_main_window = Mock()
+        config = {
+            "Test": {
+                "groups": [
+                    {"name": "Test", "actions": [{"label": "Button", "action": "action", "tooltip": "My tooltip"}]}
+                ]
+            }
+        }
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        buttons = widget.tab_widget.widget(0).findChildren(QPushButton)
+        assert buttons[0].toolTip() == "My tooltip"
+
+    def test_button_without_tooltip(self, qtbot):
+        """Test button without tooltip configured"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+        from PyQt6.QtWidgets import QPushButton
+
+        mock_main_window = Mock()
+        config = {"Test": {"groups": [{"name": "Test", "actions": [{"label": "Button", "action": "action"}]}]}}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        buttons = widget.tab_widget.widget(0).findChildren(QPushButton)
+        assert buttons[0].toolTip() == ""
+
+    def test_button_minimum_size(self, qtbot):
+        """Test that button has minimum size set"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+        from PyQt6.QtWidgets import QPushButton
+
+        mock_main_window = Mock()
+        config = {"Test": {"groups": [{"name": "Test", "actions": [{"label": "Button", "action": "action"}]}]}}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        buttons = widget.tab_widget.widget(0).findChildren(QPushButton)
+        assert buttons[0].minimumWidth() == 60
+        assert buttons[0].minimumHeight() == 40
+
+
+class TestExecuteAction:
+    """Tests for _execute_action method"""
+
+    def test_execute_action_calls_main_window_method(self, qtbot):
+        """Test that _execute_action calls the method on main_window"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+
+        mock_main_window = Mock()
+        mock_main_window.my_action = Mock()
+
+        config = {"Test": {"groups": []}}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        widget._execute_action("my_action")
+
+        mock_main_window.my_action.assert_called_once()
+
+    def test_execute_action_missing_method_prints_warning(self, qtbot, capsys):
+        """Test that _execute_action prints warning for missing method"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+
+        mock_main_window = Mock(spec=[])  # No methods
+
+        config = {"Test": {"groups": []}}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        widget._execute_action("nonexistent_action")
+
+        captured = capsys.readouterr()
+        assert "Warning" in captured.out
+        assert "nonexistent_action" in captured.out
+
+    def test_execute_action_non_callable_not_called(self, qtbot):
+        """Test that non-callable attributes are not called"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+
+        mock_main_window = Mock()
+        mock_main_window.not_a_method = "just a string"
+
+        config = {"Test": {"groups": []}}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        # Should not raise
+        widget._execute_action("not_a_method")
+
+    def test_button_click_executes_action(self, qtbot):
+        """Test that clicking a button executes the action"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+        from PyQt6.QtWidgets import QPushButton
+
+        mock_main_window = Mock()
+        mock_main_window.do_something = Mock()
+
+        config = {"Test": {"groups": [{"name": "Test", "actions": [{"label": "Do It", "action": "do_something"}]}]}}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        # Find the button and click it
+        buttons = widget.tab_widget.widget(0).findChildren(QPushButton)
+        assert len(buttons) == 1
+
+        qtbot.mouseClick(buttons[0], Qt.MouseButton.LeftButton)
+
+        mock_main_window.do_something.assert_called_once()
+
+
+class TestGroupLabel:
+    """Tests for group label creation"""
+
+    def test_group_has_label(self, qtbot):
+        """Test that group has a label"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+        from PyQt6.QtWidgets import QLabel
+
+        mock_main_window = Mock()
+        config = {"Test": {"groups": [{"name": "My Group", "actions": []}]}}
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        tab_content = widget.tab_widget.widget(0)
+        labels = tab_content.findChildren(QLabel)
+
+        # Should have at least one label with the group name
+        label_texts = [lbl.text() for lbl in labels]
+        assert "My Group" in label_texts
+
+
+class TestRibbonLayoutIntegration:
+    """Integration tests for ribbon layout"""
+
+    def test_full_ribbon_structure(self, qtbot):
+        """Test complete ribbon structure with multiple tabs and groups"""
+        from pyPhotoAlbum.ribbon_widget import RibbonWidget
+        from PyQt6.QtWidgets import QPushButton
+
+        mock_main_window = Mock()
+        config = {
+            "File": {
+                "groups": [
+                    {
+                        "name": "Project",
+                        "actions": [
+                            {"label": "New", "action": "new_project"},
+                            {"label": "Open", "action": "open_project"},
+                            {"label": "Save", "action": "save_project"},
+                        ],
+                    },
+                    {"name": "Export", "actions": [{"label": "Export PDF", "action": "export_pdf"}]},
+                ]
+            },
+            "Edit": {
+                "groups": [
+                    {
+                        "name": "Clipboard",
+                        "actions": [{"label": "Copy", "action": "copy"}, {"label": "Paste", "action": "paste"}],
+                    }
+                ]
+            },
+        }
+
+        widget = RibbonWidget(mock_main_window, ribbon_config=config)
+        qtbot.addWidget(widget)
+
+        # Check tabs
+        assert widget.tab_widget.count() == 2
+
+        # Check File tab has 4 buttons
+        file_tab = widget.tab_widget.widget(0)
+        file_buttons = file_tab.findChildren(QPushButton)
+        assert len(file_buttons) == 4
+
+        # Check Edit tab has 2 buttons
+        edit_tab = widget.tab_widget.widget(1)
+        edit_buttons = edit_tab.findChildren(QPushButton)
+        assert len(edit_buttons) == 2
+
+
+# Import Qt for click simulation
+from PyQt6.QtCore import Qt
diff --git a/tests/test_rotation_serialization.py b/tests/test_rotation_serialization.py
index 83fd042..7088695 100755
--- a/tests/test_rotation_serialization.py
+++ b/tests/test_rotation_serialization.py
@@ -19,7 +19,7 @@ class TestRotationSerialization:
     def sample_image(self):
         """Create a sample test image"""
         # Create a 400x200 test image (wider than tall)
-        img = Image.new('RGBA', (400, 200), color=(255, 0, 0, 255))
+        img = Image.new("RGBA", (400, 200), color=(255, 0, 0, 255))
         return img
 
     def test_serialize_rotation_metadata(self):
@@ -47,7 +47,7 @@ class TestRotationSerialization:
             "image_path": "test.jpg",
             "crop_info": (0, 0, 1, 1),
             "pil_rotation_90": 1,
-            "image_dimensions": (400, 200)
+            "image_dimensions": (400, 200),
         }
 
         img_data = ImageData()
@@ -71,8 +71,10 @@ class TestRotationSerialization:
         img_data._on_async_image_loaded(sample_image)
 
         # Verify dimensions are updated to rotated dimensions
-        assert img_data.image_dimensions == (200, 400), \
-            f"Expected rotated dimensions (200, 400), got {img_data.image_dimensions}"
+        assert img_data.image_dimensions == (
+            200,
+            400,
+        ), f"Expected rotated dimensions (200, 400), got {img_data.image_dimensions}"
         assert img_data._img_width == 200
         assert img_data._img_height == 400
 
@@ -143,7 +145,7 @@ class TestRotationSerialization:
             "image_path": "test.jpg",
             "crop_info": (0, 0, 1, 1),
             "pil_rotation_90": 0,  # Not set in old format
-            "image_dimensions": (400, 200)
+            "image_dimensions": (400, 200),
         }
 
         img_data = ImageData()
@@ -182,7 +184,6 @@ class TestRotationSerialization:
         img2._on_async_image_loaded(sample_image)
 
         # Verify dimensions are STILL correct after reload
-        assert img2.image_dimensions == (200, 400), \
-            "Dimensions should remain correct after reload"
+        assert img2.image_dimensions == (200, 400), "Dimensions should remain correct after reload"
         assert img2._img_width == 200
         assert img2._img_height == 400
diff --git a/tests/test_size_ops_mixin.py b/tests/test_size_ops_mixin.py
index 4913df8..58b25ae 100755
--- a/tests/test_size_ops_mixin.py
+++ b/tests/test_size_ops_mixin.py
@@ -30,7 +30,7 @@ class TestSizeWindow(SizeOperationsMixin, QMainWindow):
         return len(self.gl_widget.selected_elements) >= min_count
 
     def get_current_page(self):
-        if hasattr(self, '_current_page'):
+        if hasattr(self, "_current_page"):
             return self._current_page
         return None
 
@@ -47,7 +47,7 @@ class TestSizeWindow(SizeOperationsMixin, QMainWindow):
 class TestMakeSameSize:
     """Test make_same_size method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager")
     def test_make_same_size_success(self, mock_manager, qtbot):
         window = TestSizeWindow()
         qtbot.addWidget(window)
@@ -57,10 +57,7 @@ class TestMakeSameSize:
 
         window.gl_widget.selected_elements = {element1, element2}
 
-        mock_manager.make_same_size.return_value = [
-            (element1, (0, 0), (100, 100)),
-            (element2, (150, 0), (200, 150))
-        ]
+        mock_manager.make_same_size.return_value = [(element1, (0, 0), (100, 100)), (element2, (150, 0), (200, 150))]
 
         window.make_same_size()
 
@@ -84,7 +81,7 @@ class TestMakeSameSize:
 class TestMakeSameWidth:
     """Test make_same_width method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager")
     def test_make_same_width_success(self, mock_manager, qtbot):
         window = TestSizeWindow()
         qtbot.addWidget(window)
@@ -94,10 +91,7 @@ class TestMakeSameWidth:
 
         window.gl_widget.selected_elements = {element1, element2}
 
-        mock_manager.make_same_width.return_value = [
-            (element1, (0, 0), (100, 100)),
-            (element2, (150, 0), (200, 150))
-        ]
+        mock_manager.make_same_width.return_value = [(element1, (0, 0), (100, 100)), (element2, (150, 0), (200, 150))]
 
         window.make_same_width()
 
@@ -109,7 +103,7 @@ class TestMakeSameWidth:
 class TestMakeSameHeight:
     """Test make_same_height method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager")
     def test_make_same_height_success(self, mock_manager, qtbot):
         window = TestSizeWindow()
         qtbot.addWidget(window)
@@ -119,10 +113,7 @@ class TestMakeSameHeight:
 
         window.gl_widget.selected_elements = {element1, element2}
 
-        mock_manager.make_same_height.return_value = [
-            (element1, (0, 0), (100, 100)),
-            (element2, (150, 0), (200, 150))
-        ]
+        mock_manager.make_same_height.return_value = [(element1, (0, 0), (100, 100)), (element2, (150, 0), (200, 150))]
 
         window.make_same_height()
 
@@ -134,7 +125,7 @@ class TestMakeSameHeight:
 class TestFitToWidth:
     """Test fit_to_width method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager")
     def test_fit_to_width_success(self, mock_manager, qtbot):
         window = TestSizeWindow()
         qtbot.addWidget(window)
@@ -174,7 +165,7 @@ class TestFitToWidth:
 class TestFitToHeight:
     """Test fit_to_height method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager")
     def test_fit_to_height_success(self, mock_manager, qtbot):
         window = TestSizeWindow()
         qtbot.addWidget(window)
@@ -199,7 +190,7 @@ class TestFitToHeight:
 class TestFitToPage:
     """Test fit_to_page method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager")
     def test_fit_to_page_success(self, mock_manager, qtbot):
         window = TestSizeWindow()
         qtbot.addWidget(window)
@@ -238,7 +229,7 @@ class TestFitToPage:
 class TestSizeCommandPattern:
     """Test size operations with command pattern"""
 
-    @patch('pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager")
     def test_size_operation_creates_command(self, mock_manager, qtbot):
         window = TestSizeWindow()
         qtbot.addWidget(window)
@@ -248,10 +239,7 @@ class TestSizeCommandPattern:
 
         window.gl_widget.selected_elements = {element1, element2}
 
-        mock_manager.make_same_size.return_value = [
-            (element1, (0, 0), (100, 100)),
-            (element2, (150, 0), (200, 150))
-        ]
+        mock_manager.make_same_size.return_value = [(element1, (0, 0), (100, 100)), (element2, (150, 0), (200, 150))]
 
         assert not window.project.history.can_undo()
 
@@ -259,7 +247,7 @@ class TestSizeCommandPattern:
 
         assert window.project.history.can_undo()
 
-    @patch('pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager")
     def test_fit_operation_creates_command(self, mock_manager, qtbot):
         window = TestSizeWindow()
         qtbot.addWidget(window)
@@ -284,7 +272,7 @@ class TestSizeCommandPattern:
 class TestExpandImage:
     """Test expand_image method"""
 
-    @patch('pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager')
+    @patch("pyPhotoAlbum.mixins.operations.size_ops.AlignmentManager")
     def test_expand_image_success(self, mock_manager, qtbot):
         window = TestSizeWindow()
         qtbot.addWidget(window)
diff --git a/tests/test_snapping.py b/tests/test_snapping.py
index 9f26e0e..bd02279 100755
--- a/tests/test_snapping.py
+++ b/tests/test_snapping.py
@@ -11,25 +11,25 @@ class TestGuide:
 
     def test_guide_initialization(self):
         """Test Guide initialization"""
-        guide = Guide(position=50.0, orientation='vertical')
+        guide = Guide(position=50.0, orientation="vertical")
         assert guide.position == 50.0
-        assert guide.orientation == 'vertical'
+        assert guide.orientation == "vertical"
 
     def test_guide_serialization(self):
         """Test Guide serialization to dictionary"""
-        guide = Guide(position=75.5, orientation='horizontal')
+        guide = Guide(position=75.5, orientation="horizontal")
         data = guide.serialize()
 
-        assert data['position'] == 75.5
-        assert data['orientation'] == 'horizontal'
+        assert data["position"] == 75.5
+        assert data["orientation"] == "horizontal"
 
     def test_guide_deserialization(self):
         """Test Guide deserialization from dictionary"""
-        data = {'position': 100.0, 'orientation': 'vertical'}
+        data = {"position": 100.0, "orientation": "vertical"}
         guide = Guide.deserialize(data)
 
         assert guide.position == 100.0
-        assert guide.orientation == 'vertical'
+        assert guide.orientation == "vertical"
 
     def test_guide_deserialization_with_defaults(self):
         """Test Guide deserialization with missing fields uses defaults"""
@@ -37,7 +37,7 @@ class TestGuide:
         guide = Guide.deserialize(data)
 
         assert guide.position == 0
-        assert guide.orientation == 'vertical'
+        assert guide.orientation == "vertical"
 
 
 class TestSnappingSystem:
@@ -46,7 +46,7 @@ class TestSnappingSystem:
     def test_initialization_default(self):
         """Test SnappingSystem initialization with default values"""
         system = SnappingSystem()
-        
+
         assert system.snap_threshold_mm == 5.0
         assert system.grid_size_mm == 10.0
         assert system.snap_to_grid == False
@@ -62,19 +62,19 @@ class TestSnappingSystem:
     def test_add_guide(self):
         """Test adding a guide"""
         system = SnappingSystem()
-        guide = system.add_guide(position=50.0, orientation='vertical')
+        guide = system.add_guide(position=50.0, orientation="vertical")
 
         assert len(system.guides) == 1
         assert guide.position == 50.0
-        assert guide.orientation == 'vertical'
+        assert guide.orientation == "vertical"
         assert guide in system.guides
 
     def test_add_multiple_guides(self):
         """Test adding multiple guides"""
         system = SnappingSystem()
-        guide1 = system.add_guide(position=50.0, orientation='vertical')
-        guide2 = system.add_guide(position=100.0, orientation='horizontal')
-        guide3 = system.add_guide(position=150.0, orientation='vertical')
+        guide1 = system.add_guide(position=50.0, orientation="vertical")
+        guide2 = system.add_guide(position=100.0, orientation="horizontal")
+        guide3 = system.add_guide(position=150.0, orientation="vertical")
 
         assert len(system.guides) == 3
         assert guide1 in system.guides
@@ -84,8 +84,8 @@ class TestSnappingSystem:
     def test_remove_guide(self):
         """Test removing a guide"""
         system = SnappingSystem()
-        guide = system.add_guide(position=50.0, orientation='vertical')
-        
+        guide = system.add_guide(position=50.0, orientation="vertical")
+
         system.remove_guide(guide)
         assert len(system.guides) == 0
         assert guide not in system.guides
@@ -93,9 +93,9 @@ class TestSnappingSystem:
     def test_remove_guide_not_in_list(self):
         """Test removing a guide that's not in the list does nothing"""
         system = SnappingSystem()
-        guide1 = system.add_guide(position=50.0, orientation='vertical')
-        guide2 = Guide(position=100.0, orientation='horizontal')
-        
+        guide1 = system.add_guide(position=50.0, orientation="vertical")
+        guide2 = Guide(position=100.0, orientation="horizontal")
+
         # Should not raise an error
         system.remove_guide(guide2)
         assert len(system.guides) == 1
@@ -104,9 +104,9 @@ class TestSnappingSystem:
     def test_clear_guides(self):
         """Test clearing all guides"""
         system = SnappingSystem()
-        system.add_guide(position=50.0, orientation='vertical')
-        system.add_guide(position=100.0, orientation='horizontal')
-        system.add_guide(position=150.0, orientation='vertical')
+        system.add_guide(position=50.0, orientation="vertical")
+        system.add_guide(position=100.0, orientation="horizontal")
+        system.add_guide(position=150.0, orientation="vertical")
 
         system.clear_guides()
         assert len(system.guides) == 0
@@ -151,13 +151,13 @@ class TestSnappingSystem:
         # Position near a grid line
         dpi = 300
         grid_size_px = 10.0 * dpi / 25.4  # ~118 pixels
-        
+
         position = (grid_size_px + 5, grid_size_px + 5)  # Close to a grid point
         size = (100.0, 100.0)
         page_size = (210.0, 297.0)
 
         snapped = system.snap_position(position, size, page_size, dpi=dpi)
-        
+
         # Should snap to nearest grid line
         assert abs(snapped[0] - grid_size_px) < 1  # Allow small floating point error
         assert abs(snapped[1] - grid_size_px) < 1
@@ -173,8 +173,8 @@ class TestSnappingSystem:
         guide_pos_mm = 50.0
         guide_pos_px = guide_pos_mm * dpi / 25.4
 
-        system.add_guide(position=guide_pos_mm, orientation='vertical')
-        system.add_guide(position=guide_pos_mm, orientation='horizontal')
+        system.add_guide(position=guide_pos_mm, orientation="vertical")
+        system.add_guide(position=guide_pos_mm, orientation="horizontal")
 
         # Position near the guides
         position = (guide_pos_px + 5, guide_pos_px + 5)
@@ -182,7 +182,7 @@ class TestSnappingSystem:
         page_size = (210.0, 297.0)
 
         snapped = system.snap_position(position, size, page_size, dpi=dpi)
-        
+
         # Should snap to guides
         assert abs(snapped[0] - guide_pos_px) < 1
         assert abs(snapped[1] - guide_pos_px) < 1
@@ -203,6 +203,7 @@ class TestSnappingSystem:
     def test_snap_resize_bottom_right_handle(self):
         """Test snap_resize with bottom-right handle"""
         from pyPhotoAlbum.snapping import SnapResizeParams
+
         system = SnappingSystem(snap_threshold_mm=5.0)
         system.snap_to_grid = True
         system.grid_size_mm = 10.0
@@ -211,17 +212,11 @@ class TestSnappingSystem:
         size = (200.0, 200.0)
         dx = 10.0
         dy = 10.0
-        resize_handle = 'se'
+        resize_handle = "se"
         page_size = (210.0, 297.0)
 
         params = SnapResizeParams(
-            position=position,
-            size=size,
-            dx=dx,
-            dy=dy,
-            resize_handle=resize_handle,
-            page_size=page_size,
-            dpi=300
+            position=position, size=size, dx=dx, dy=dy, resize_handle=resize_handle, page_size=page_size, dpi=300
         )
         new_pos, new_size = system.snap_resize(params)
 
@@ -234,6 +229,7 @@ class TestSnappingSystem:
     def test_snap_resize_top_left_handle(self):
         """Test snap_resize with top-left handle"""
         from pyPhotoAlbum.snapping import SnapResizeParams
+
         system = SnappingSystem(snap_threshold_mm=5.0)
         system.snap_to_edges = True
 
@@ -241,11 +237,12 @@ class TestSnappingSystem:
         size = (200.0, 200.0)
         dx = -10.0
         dy = -10.0
-        resize_handle = 'nw'
+        resize_handle = "nw"
         page_size = (210.0, 297.0)
 
-        params = SnapResizeParams(position=position, size=size, dx=dx, dy=dy,
-                                 resize_handle=resize_handle, page_size=page_size, dpi=300)
+        params = SnapResizeParams(
+            position=position, size=size, dx=dx, dy=dy, resize_handle=resize_handle, page_size=page_size, dpi=300
+        )
         new_pos, new_size = system.snap_resize(params)
 
         # Both position and size should change for top-left handle
@@ -255,6 +252,7 @@ class TestSnappingSystem:
     def test_snap_resize_top_handle(self):
         """Test snap_resize with top handle only"""
         from pyPhotoAlbum.snapping import SnapResizeParams
+
         system = SnappingSystem(snap_threshold_mm=5.0)
         system.snap_to_edges = True
 
@@ -262,11 +260,12 @@ class TestSnappingSystem:
         size = (200.0, 200.0)
         dx = 0.0
         dy = -10.0
-        resize_handle = 'n'
+        resize_handle = "n"
         page_size = (210.0, 297.0)
 
-        params = SnapResizeParams(position=position, size=size, dx=dx, dy=dy,
-                                 resize_handle=resize_handle, page_size=page_size, dpi=300)
+        params = SnapResizeParams(
+            position=position, size=size, dx=dx, dy=dy, resize_handle=resize_handle, page_size=page_size, dpi=300
+        )
         new_pos, new_size = system.snap_resize(params)
 
         # X position should stay same, Y should change
@@ -279,6 +278,7 @@ class TestSnappingSystem:
     def test_snap_resize_right_handle(self):
         """Test snap_resize with right handle only"""
         from pyPhotoAlbum.snapping import SnapResizeParams
+
         system = SnappingSystem(snap_threshold_mm=5.0)
         system.snap_to_edges = True
 
@@ -286,11 +286,12 @@ class TestSnappingSystem:
         size = (200.0, 200.0)
         dx = 10.0
         dy = 0.0
-        resize_handle = 'e'
+        resize_handle = "e"
         page_size = (210.0, 297.0)
 
-        params = SnapResizeParams(position=position, size=size, dx=dx, dy=dy,
-                                 resize_handle=resize_handle, page_size=page_size, dpi=300)
+        params = SnapResizeParams(
+            position=position, size=size, dx=dx, dy=dy, resize_handle=resize_handle, page_size=page_size, dpi=300
+        )
         new_pos, new_size = system.snap_resize(params)
 
         # Position should stay same
@@ -302,6 +303,7 @@ class TestSnappingSystem:
     def test_snap_resize_minimum_size(self):
         """Test snap_resize enforces minimum size"""
         from pyPhotoAlbum.snapping import SnapResizeParams
+
         system = SnappingSystem(snap_threshold_mm=5.0)
         system.snap_to_edges = False
 
@@ -309,11 +311,12 @@ class TestSnappingSystem:
         size = (50.0, 50.0)
         dx = -100.0  # Try to make it very small
         dy = -100.0
-        resize_handle = 'se'
+        resize_handle = "se"
         page_size = (210.0, 297.0)
 
-        params = SnapResizeParams(position=position, size=size, dx=dx, dy=dy,
-                                 resize_handle=resize_handle, page_size=page_size, dpi=300)
+        params = SnapResizeParams(
+            position=position, size=size, dx=dx, dy=dy, resize_handle=resize_handle, page_size=page_size, dpi=300
+        )
         new_pos, new_size = system.snap_resize(params)
 
         # Should enforce minimum size of 10 pixels
@@ -323,6 +326,7 @@ class TestSnappingSystem:
     def test_snap_resize_all_handles(self):
         """Test snap_resize works with all handle types"""
         from pyPhotoAlbum.snapping import SnapResizeParams
+
         system = SnappingSystem(snap_threshold_mm=5.0)
         system.snap_to_edges = False
 
@@ -332,11 +336,12 @@ class TestSnappingSystem:
         dy = 10.0
         page_size = (210.0, 297.0)
 
-        handles = ['nw', 'n', 'ne', 'e', 'se', 's', 'sw', 'w']
+        handles = ["nw", "n", "ne", "e", "se", "s", "sw", "w"]
 
         for handle in handles:
-            params = SnapResizeParams(position=position, size=size, dx=dx, dy=dy,
-                                     resize_handle=handle, page_size=page_size, dpi=300)
+            params = SnapResizeParams(
+                position=position, size=size, dx=dx, dy=dy, resize_handle=handle, page_size=page_size, dpi=300
+            )
             new_pos, new_size = system.snap_resize(params)
             # Should return valid position and size
             assert isinstance(new_pos, tuple)
@@ -356,9 +361,9 @@ class TestSnappingSystem:
         page_size = (210.0, 297.0)
         lines = system.get_snap_lines(page_size, dpi=300)
 
-        assert lines['grid'] == []
-        assert lines['edges'] == []
-        assert lines['guides'] == []
+        assert lines["grid"] == []
+        assert lines["edges"] == []
+        assert lines["guides"] == []
 
     def test_get_snap_lines_with_grid(self):
         """Test get_snap_lines with grid enabled"""
@@ -370,11 +375,11 @@ class TestSnappingSystem:
         lines = system.get_snap_lines(page_size, dpi=300)
 
         # Should have grid lines
-        assert len(lines['grid']) > 0
-        
+        assert len(lines["grid"]) > 0
+
         # Should have both vertical and horizontal grid lines
-        vertical_lines = [line for line in lines['grid'] if line[0] == 'vertical']
-        horizontal_lines = [line for line in lines['grid'] if line[0] == 'horizontal']
+        vertical_lines = [line for line in lines["grid"] if line[0] == "vertical"]
+        horizontal_lines = [line for line in lines["grid"] if line[0] == "horizontal"]
         assert len(vertical_lines) > 0
         assert len(horizontal_lines) > 0
 
@@ -387,34 +392,34 @@ class TestSnappingSystem:
         lines = system.get_snap_lines(page_size, dpi=300)
 
         # Should have exactly 4 edge lines (left, right, top, bottom)
-        assert len(lines['edges']) == 4
-        
+        assert len(lines["edges"]) == 4
+
         # Check for vertical edges
-        vertical_edges = [line for line in lines['edges'] if line[0] == 'vertical']
+        vertical_edges = [line for line in lines["edges"] if line[0] == "vertical"]
         assert len(vertical_edges) == 2
-        
+
         # Check for horizontal edges
-        horizontal_edges = [line for line in lines['edges'] if line[0] == 'horizontal']
+        horizontal_edges = [line for line in lines["edges"] if line[0] == "horizontal"]
         assert len(horizontal_edges) == 2
 
     def test_get_snap_lines_with_guides(self):
         """Test get_snap_lines with guides"""
         system = SnappingSystem()
         system.snap_to_guides = True
-        
-        system.add_guide(position=50.0, orientation='vertical')
-        system.add_guide(position=100.0, orientation='horizontal')
-        system.add_guide(position=150.0, orientation='vertical')
+
+        system.add_guide(position=50.0, orientation="vertical")
+        system.add_guide(position=100.0, orientation="horizontal")
+        system.add_guide(position=150.0, orientation="vertical")
 
         page_size = (210.0, 297.0)
         lines = system.get_snap_lines(page_size, dpi=300)
 
         # Should have guide lines
-        assert len(lines['guides']) == 3
-        
+        assert len(lines["guides"]) == 3
+
         # Check orientations
-        vertical_guides = [line for line in lines['guides'] if line[0] == 'vertical']
-        horizontal_guides = [line for line in lines['guides'] if line[0] == 'horizontal']
+        vertical_guides = [line for line in lines["guides"] if line[0] == "vertical"]
+        horizontal_guides = [line for line in lines["guides"] if line[0] == "horizontal"]
         assert len(vertical_guides) == 2
         assert len(horizontal_guides) == 1
 
@@ -425,35 +430,32 @@ class TestSnappingSystem:
         system.snap_to_grid = True
         system.snap_to_edges = False
         system.snap_to_guides = True
-        
-        system.add_guide(position=50.0, orientation='vertical')
-        system.add_guide(position=100.0, orientation='horizontal')
+
+        system.add_guide(position=50.0, orientation="vertical")
+        system.add_guide(position=100.0, orientation="horizontal")
 
         data = system.serialize()
 
-        assert data['snap_threshold_mm'] == 3.0
-        assert data['grid_size_mm'] == 15.0
-        assert data['snap_to_grid'] == True
-        assert data['snap_to_edges'] == False
-        assert data['snap_to_guides'] == True
-        assert len(data['guides']) == 2
+        assert data["snap_threshold_mm"] == 3.0
+        assert data["grid_size_mm"] == 15.0
+        assert data["snap_to_grid"] == True
+        assert data["snap_to_edges"] == False
+        assert data["snap_to_guides"] == True
+        assert len(data["guides"]) == 2
 
     def test_deserialization(self):
         """Test SnappingSystem deserialization from dictionary"""
         system = SnappingSystem()
-        
+
         data = {
-            'snap_threshold_mm': 4.0,
-            'grid_size_mm': 20.0,
-            'snap_to_grid': True,
-            'snap_to_edges': False,
-            'snap_to_guides': True,
-            'guides': [
-                {'position': 50.0, 'orientation': 'vertical'},
-                {'position': 100.0, 'orientation': 'horizontal'}
-            ]
+            "snap_threshold_mm": 4.0,
+            "grid_size_mm": 20.0,
+            "snap_to_grid": True,
+            "snap_to_edges": False,
+            "snap_to_guides": True,
+            "guides": [{"position": 50.0, "orientation": "vertical"}, {"position": 100.0, "orientation": "horizontal"}],
         }
-        
+
         system.deserialize(data)
 
         assert system.snap_threshold_mm == 4.0
@@ -463,15 +465,15 @@ class TestSnappingSystem:
         assert system.snap_to_guides == True
         assert len(system.guides) == 2
         assert system.guides[0].position == 50.0
-        assert system.guides[0].orientation == 'vertical'
+        assert system.guides[0].orientation == "vertical"
         assert system.guides[1].position == 100.0
-        assert system.guides[1].orientation == 'horizontal'
+        assert system.guides[1].orientation == "horizontal"
 
     def test_deserialization_with_defaults(self):
         """Test SnappingSystem deserialization with missing fields uses defaults"""
         system = SnappingSystem()
         data = {}
-        
+
         system.deserialize(data)
 
         assert system.snap_threshold_mm == 5.0
@@ -488,10 +490,10 @@ class TestSnappingSystem:
         original.snap_to_grid = True
         original.snap_to_edges = True
         original.snap_to_guides = False
-        
-        original.add_guide(position=25.5, orientation='vertical')
-        original.add_guide(position=75.5, orientation='horizontal')
-        original.add_guide(position=125.5, orientation='vertical')
+
+        original.add_guide(position=25.5, orientation="vertical")
+        original.add_guide(position=75.5, orientation="horizontal")
+        original.add_guide(position=125.5, orientation="vertical")
 
         data = original.serialize()
         restored = SnappingSystem()
@@ -503,7 +505,7 @@ class TestSnappingSystem:
         assert restored.snap_to_edges == original.snap_to_edges
         assert restored.snap_to_guides == original.snap_to_guides
         assert len(restored.guides) == len(original.guides)
-        
+
         for orig_guide, rest_guide in zip(original.guides, restored.guides):
             assert rest_guide.position == orig_guide.position
             assert rest_guide.orientation == orig_guide.orientation
diff --git a/tests/test_snapping_system.py b/tests/test_snapping_system.py
new file mode 100644
index 0000000..615a5bd
--- /dev/null
+++ b/tests/test_snapping_system.py
@@ -0,0 +1,630 @@
+"""
+Comprehensive tests for SnappingSystem
+"""
+
+import pytest
+import math
+from unittest.mock import Mock
+
+from pyPhotoAlbum.snapping import SnappingSystem, Guide, SnapResizeParams
+
+
+class TestGuide:
+    """Tests for Guide dataclass"""
+
+    def test_guide_creation(self):
+        """Test creating a Guide"""
+        guide = Guide(position=100.0, orientation="vertical")
+        assert guide.position == 100.0
+        assert guide.orientation == "vertical"
+
+    def test_guide_serialize(self):
+        """Test Guide serialization"""
+        guide = Guide(position=50.5, orientation="horizontal")
+        data = guide.serialize()
+
+        assert data["position"] == 50.5
+        assert data["orientation"] == "horizontal"
+
+    def test_guide_deserialize(self):
+        """Test Guide deserialization"""
+        data = {"position": 75.0, "orientation": "vertical"}
+        guide = Guide.deserialize(data)
+
+        assert guide.position == 75.0
+        assert guide.orientation == "vertical"
+
+    def test_guide_deserialize_defaults(self):
+        """Test Guide deserialization with missing fields"""
+        guide = Guide.deserialize({})
+
+        assert guide.position == 0
+        assert guide.orientation == "vertical"
+
+
+class TestSnappingSystemInit:
+    """Tests for SnappingSystem initialization"""
+
+    def test_default_init(self):
+        """Test default initialization"""
+        snap = SnappingSystem()
+
+        assert snap.snap_threshold_mm == 5.0
+        assert snap.grid_size_mm == 10.0
+        assert snap.snap_to_grid is False
+        assert snap.snap_to_edges is True
+        assert snap.snap_to_guides is True
+        assert snap.guides == []
+
+    def test_custom_threshold(self):
+        """Test initialization with custom threshold"""
+        snap = SnappingSystem(snap_threshold_mm=10.0)
+        assert snap.snap_threshold_mm == 10.0
+
+
+class TestGuideManagement:
+    """Tests for guide management methods"""
+
+    def test_add_guide(self):
+        """Test adding a guide"""
+        snap = SnappingSystem()
+        guide = snap.add_guide(100.0, "vertical")
+
+        assert len(snap.guides) == 1
+        assert snap.guides[0].position == 100.0
+        assert snap.guides[0].orientation == "vertical"
+
+    def test_add_multiple_guides(self):
+        """Test adding multiple guides"""
+        snap = SnappingSystem()
+        snap.add_guide(50.0, "horizontal")
+        snap.add_guide(100.0, "vertical")
+        snap.add_guide(150.0, "horizontal")
+
+        assert len(snap.guides) == 3
+
+    def test_remove_guide(self):
+        """Test removing a guide"""
+        snap = SnappingSystem()
+        guide = snap.add_guide(100.0, "vertical")
+
+        snap.remove_guide(guide)
+
+        assert len(snap.guides) == 0
+
+    def test_remove_nonexistent_guide(self):
+        """Test removing a guide that doesn't exist"""
+        snap = SnappingSystem()
+        guide = Guide(position=100.0, orientation="vertical")
+
+        # Should not raise exception
+        snap.remove_guide(guide)
+        assert len(snap.guides) == 0
+
+    def test_clear_guides(self):
+        """Test clearing all guides"""
+        snap = SnappingSystem()
+        snap.add_guide(50.0, "horizontal")
+        snap.add_guide(100.0, "vertical")
+        snap.add_guide(150.0, "horizontal")
+
+        snap.clear_guides()
+
+        assert len(snap.guides) == 0
+
+
+class TestSnapPosition:
+    """Tests for snap_position method"""
+
+    def test_no_snapping_when_disabled(self):
+        """Test that no snapping occurs when all snapping is disabled"""
+        snap = SnappingSystem()
+        snap.snap_to_grid = False
+        snap.snap_to_edges = False
+        snap.snap_to_guides = False
+
+        position = (100, 100)
+        size = (50, 50)
+        page_size = (210, 297)  # A4 in mm
+
+        result = snap.snap_position(position, size, page_size)
+
+        assert result == position
+
+    def test_snap_to_left_edge(self):
+        """Test snapping to left page edge"""
+        snap = SnappingSystem(snap_threshold_mm=10.0)
+        snap.snap_to_edges = True
+        snap.snap_to_grid = False
+        snap.snap_to_guides = False
+
+        # Position close to left edge (within threshold)
+        # At 300 DPI, 10mm = ~118 pixels
+        position = (5, 100)  # Very close to left edge (0)
+        size = (50, 50)
+        page_size = (210, 297)
+
+        result = snap.snap_position(position, size, page_size)
+
+        # Should snap to 0 (left edge)
+        assert result[0] == 0
+
+    def test_snap_to_right_edge(self):
+        """Test snapping to right page edge"""
+        snap = SnappingSystem(snap_threshold_mm=10.0)
+        snap.snap_to_edges = True
+        snap.snap_to_grid = False
+        snap.snap_to_guides = False
+
+        dpi = 300
+        page_width_mm = 210
+        page_width_px = page_width_mm * dpi / 25.4
+        element_width = 50
+
+        # Position close to right edge
+        position = (page_width_px - element_width - 5, 100)
+        size = (element_width, 50)
+        page_size = (page_width_mm, 297)
+
+        result = snap.snap_position(position, size, page_size, dpi)
+
+        # Should snap so element's right edge aligns with page right edge
+        expected_x = page_width_px - element_width
+        assert abs(result[0] - expected_x) < 1
+
+    def test_snap_to_grid(self):
+        """Test snapping to grid"""
+        snap = SnappingSystem(snap_threshold_mm=5.0)
+        snap.snap_to_grid = True
+        snap.snap_to_edges = False
+        snap.snap_to_guides = False
+        snap.grid_size_mm = 10.0
+
+        dpi = 300
+        grid_size_px = 10.0 * dpi / 25.4  # ~118 pixels
+
+        # Position slightly off grid
+        position = (grid_size_px + 10, grid_size_px + 10)
+        size = (50, 50)
+        page_size = (210, 297)
+
+        result = snap.snap_position(position, size, page_size, dpi)
+
+        # Should snap to nearest grid intersection
+        assert abs(result[0] - grid_size_px) < 1 or abs(result[0] - 2 * grid_size_px) < 1
+
+    def test_snap_to_guides(self):
+        """Test snapping to guides"""
+        snap = SnappingSystem(snap_threshold_mm=10.0)
+        snap.snap_to_edges = False
+        snap.snap_to_grid = False
+        snap.snap_to_guides = True
+
+        dpi = 300
+        guide_pos_mm = 50.0
+        guide_pos_px = guide_pos_mm * dpi / 25.4
+
+        snap.add_guide(guide_pos_mm, "vertical")
+        snap.add_guide(guide_pos_mm, "horizontal")
+
+        # Position close to guide intersection
+        position = (guide_pos_px + 5, guide_pos_px + 5)
+        size = (50, 50)
+        page_size = (210, 297)
+
+        result = snap.snap_position(position, size, page_size, dpi)
+
+        # Should snap to guide intersection
+        assert abs(result[0] - guide_pos_px) < 1 or abs(result[1] - guide_pos_px) < 1
+
+    def test_snap_uses_euclidean_distance(self):
+        """Test that snapping uses Euclidean distance for point selection"""
+        snap = SnappingSystem(snap_threshold_mm=20.0)
+        snap.snap_to_edges = True
+        snap.snap_to_grid = False
+        snap.snap_to_guides = False
+
+        # Position close to origin - should snap to (0, 0)
+        # At 300 DPI, 20mm threshold = ~236 pixels
+        # Position (50, 50) has euclidean distance ~70.7 from (0, 0)
+        # which is well within the threshold
+        position = (50, 50)
+        size = (50, 50)
+        page_size = (210, 297)
+        dpi = 300
+
+        result = snap.snap_position(position, size, page_size, dpi)
+
+        # Should snap to (0, 0) corner as it's closest and within threshold
+        # Note: snap_position considers multiple snap points; check we got one of them
+        assert result[0] == 0 or result[1] == 0, f"Expected at least one axis to snap to 0, got {result}"
+
+    def test_snap_with_project_settings(self):
+        """Test snapping with project settings override"""
+        snap = SnappingSystem()
+        snap.snap_to_grid = False  # Local setting
+
+        mock_project = Mock()
+        mock_project.snap_to_grid = True
+        mock_project.snap_to_edges = False
+        mock_project.snap_to_guides = False
+        mock_project.grid_size_mm = 10.0
+        mock_project.snap_threshold_mm = 5.0
+
+        dpi = 300
+        grid_size_px = 10.0 * dpi / 25.4
+
+        # Position near grid line
+        position = (grid_size_px + 5, grid_size_px + 5)
+        size = (50, 50)
+        page_size = (210, 297)
+
+        result = snap.snap_position(position, size, page_size, dpi, mock_project)
+
+        # Should use project settings and snap to grid
+        # The result should be different from input (snapped)
+        assert result != position
+
+
+class TestSnapResize:
+    """Tests for snap_resize method"""
+
+    def test_resize_southeast_handle(self):
+        """Test resizing from SE corner"""
+        snap = SnappingSystem()
+        snap.snap_to_edges = False
+        snap.snap_to_grid = False
+        snap.snap_to_guides = False
+
+        params = SnapResizeParams(
+            position=(100, 100), size=(100, 100), dx=50, dy=50, resize_handle="se", page_size=(210, 297)
+        )
+
+        new_pos, new_size = snap.snap_resize(params)
+
+        # Position should stay same for SE resize
+        assert new_pos == (100, 100)
+        # Size should increase
+        assert new_size == (150, 150)
+
+    def test_resize_northwest_handle(self):
+        """Test resizing from NW corner"""
+        snap = SnappingSystem()
+        snap.snap_to_edges = False
+        snap.snap_to_grid = False
+        snap.snap_to_guides = False
+
+        params = SnapResizeParams(
+            position=(100, 100), size=(100, 100), dx=-20, dy=-20, resize_handle="nw", page_size=(210, 297)
+        )
+
+        new_pos, new_size = snap.snap_resize(params)
+
+        # Position should move for NW resize
+        assert new_pos == (80, 80)
+        # Size should increase
+        assert new_size == (120, 120)
+
+    def test_resize_minimum_size(self):
+        """Test that resize enforces minimum size"""
+        snap = SnappingSystem()
+        snap.snap_to_edges = False
+        snap.snap_to_grid = False
+        snap.snap_to_guides = False
+
+        params = SnapResizeParams(
+            position=(100, 100),
+            size=(50, 50),
+            dx=-100,  # Would make width negative
+            dy=-100,  # Would make height negative
+            resize_handle="se",
+            page_size=(210, 297),
+        )
+
+        new_pos, new_size = snap.snap_resize(params)
+
+        # Size should be clamped to minimum
+        assert new_size[0] >= 10
+        assert new_size[1] >= 10
+
+    def test_resize_snap_to_edge(self):
+        """Test that resize snaps edges to page boundaries"""
+        snap = SnappingSystem(snap_threshold_mm=10.0)
+        snap.snap_to_edges = True
+        snap.snap_to_grid = False
+        snap.snap_to_guides = False
+
+        dpi = 300
+        page_width_px = 210 * dpi / 25.4
+
+        params = SnapResizeParams(
+            position=(100, 100),
+            size=(100, 100),
+            dx=page_width_px - 200 - 5,  # Almost to right edge
+            dy=0,
+            resize_handle="e",
+            page_size=(210, 297),
+            dpi=dpi,
+        )
+
+        new_pos, new_size = snap.snap_resize(params)
+
+        # Right edge should snap to page edge
+        right_edge = new_pos[0] + new_size[0]
+        assert abs(right_edge - page_width_px) < 20  # Within snap threshold
+
+
+class TestSnapEdgeToTargets:
+    """Tests for _snap_edge_to_targets method"""
+
+    def test_snap_to_page_start_edge(self):
+        """Test snapping to page start edge (0)"""
+        snap = SnappingSystem()
+        snap.snap_to_edges = True
+        snap.snap_to_grid = False
+        snap.snap_to_guides = False
+
+        dpi = 300
+        threshold_px = 50
+
+        result = snap._snap_edge_to_targets(
+            edge_position=10, page_size_mm=210, dpi=dpi, snap_threshold_px=threshold_px, orientation="vertical"
+        )
+
+        assert result == 0
+
+    def test_snap_to_page_end_edge(self):
+        """Test snapping to page end edge"""
+        snap = SnappingSystem()
+        snap.snap_to_edges = True
+        snap.snap_to_grid = False
+        snap.snap_to_guides = False
+
+        dpi = 300
+        page_size_mm = 210
+        page_size_px = page_size_mm * dpi / 25.4
+        threshold_px = 50
+
+        result = snap._snap_edge_to_targets(
+            edge_position=page_size_px - 10,
+            page_size_mm=page_size_mm,
+            dpi=dpi,
+            snap_threshold_px=threshold_px,
+            orientation="vertical",
+        )
+
+        assert result == page_size_px
+
+    def test_snap_to_grid_line(self):
+        """Test snapping to grid line"""
+        snap = SnappingSystem()
+        snap.snap_to_edges = False
+        snap.snap_to_grid = True
+        snap.snap_to_guides = False
+        snap.grid_size_mm = 10.0
+
+        dpi = 300
+        grid_size_px = 10.0 * dpi / 25.4
+        threshold_px = 50
+
+        result = snap._snap_edge_to_targets(
+            edge_position=grid_size_px + 5,
+            page_size_mm=210,
+            dpi=dpi,
+            snap_threshold_px=threshold_px,
+            orientation="vertical",
+        )
+
+        assert result == grid_size_px
+
+    def test_snap_to_guide(self):
+        """Test snapping to guide"""
+        snap = SnappingSystem()
+        snap.snap_to_edges = False
+        snap.snap_to_grid = False
+        snap.snap_to_guides = True
+
+        guide_pos_mm = 50.0
+        snap.add_guide(guide_pos_mm, "vertical")
+
+        dpi = 300
+        guide_pos_px = guide_pos_mm * dpi / 25.4
+        threshold_px = 50
+
+        result = snap._snap_edge_to_targets(
+            edge_position=guide_pos_px + 5,
+            page_size_mm=210,
+            dpi=dpi,
+            snap_threshold_px=threshold_px,
+            orientation="vertical",
+        )
+
+        assert result == guide_pos_px
+
+    def test_no_snap_when_out_of_threshold(self):
+        """Test no snap when edge is outside threshold"""
+        snap = SnappingSystem()
+        snap.snap_to_edges = True
+        snap.snap_to_grid = False
+        snap.snap_to_guides = False
+
+        dpi = 300
+        threshold_px = 10
+
+        result = snap._snap_edge_to_targets(
+            edge_position=500,  # Far from any edge
+            page_size_mm=210,
+            dpi=dpi,
+            snap_threshold_px=threshold_px,
+            orientation="vertical",
+        )
+
+        assert result is None
+
+
+class TestSnapAxis:
+    """Tests for _snap_axis method"""
+
+    def test_snap_axis_to_start(self):
+        """Test snapping axis to start edge"""
+        snap = SnappingSystem()
+        snap.snap_to_edges = True
+        snap.snap_to_grid = False
+        snap.snap_to_guides = False
+
+        dpi = 300
+        threshold_px = 50
+
+        result = snap._snap_axis(
+            position=10, size=50, page_size_mm=210, dpi=dpi, snap_threshold_px=threshold_px, orientation="vertical"
+        )
+
+        assert result == 0
+
+    def test_snap_axis_to_end(self):
+        """Test snapping axis so element end aligns with page end"""
+        snap = SnappingSystem()
+        snap.snap_to_edges = True
+        snap.snap_to_grid = False
+        snap.snap_to_guides = False
+
+        dpi = 300
+        page_size_mm = 210
+        page_size_px = page_size_mm * dpi / 25.4
+        element_size = 50
+        threshold_px = 50
+
+        result = snap._snap_axis(
+            position=page_size_px - element_size - 10,
+            size=element_size,
+            page_size_mm=page_size_mm,
+            dpi=dpi,
+            snap_threshold_px=threshold_px,
+            orientation="vertical",
+        )
+
+        expected = page_size_px - element_size
+        assert abs(result - expected) < 1
+
+
+class TestGetSnapLines:
+    """Tests for get_snap_lines method"""
+
+    def test_get_snap_lines_edges_only(self):
+        """Test getting snap lines with edges only"""
+        snap = SnappingSystem()
+        snap.snap_to_edges = True
+        snap.snap_to_grid = False
+        snap.snap_to_guides = False
+
+        result = snap.get_snap_lines((210, 297))
+
+        assert len(result["edges"]) == 4  # 4 edges
+        assert len(result["grid"]) == 0
+        assert len(result["guides"]) == 0
+
+    def test_get_snap_lines_with_grid(self):
+        """Test getting snap lines with grid enabled"""
+        snap = SnappingSystem()
+        snap.snap_to_edges = False
+        snap.snap_to_grid = True
+        snap.snap_to_guides = False
+        snap.grid_size_mm = 10.0
+
+        result = snap.get_snap_lines((100, 100), dpi=300)
+
+        # Should have multiple grid lines
+        assert len(result["grid"]) > 0
+        assert len(result["edges"]) == 0
+
+    def test_get_snap_lines_with_guides(self):
+        """Test getting snap lines with guides"""
+        snap = SnappingSystem()
+        snap.snap_to_edges = False
+        snap.snap_to_grid = False
+        snap.snap_to_guides = True
+
+        snap.add_guide(50.0, "vertical")
+        snap.add_guide(100.0, "horizontal")
+
+        result = snap.get_snap_lines((210, 297))
+
+        assert len(result["guides"]) == 2
+
+
+class TestSerialization:
+    """Tests for serialize/deserialize methods"""
+
+    def test_serialize(self):
+        """Test serialization"""
+        snap = SnappingSystem(snap_threshold_mm=8.0)
+        snap.grid_size_mm = 15.0
+        snap.snap_to_grid = True
+        snap.snap_to_edges = False
+        snap.add_guide(50.0, "vertical")
+        snap.add_guide(100.0, "horizontal")
+
+        data = snap.serialize()
+
+        assert data["snap_threshold_mm"] == 8.0
+        assert data["grid_size_mm"] == 15.0
+        assert data["snap_to_grid"] is True
+        assert data["snap_to_edges"] is False
+        assert data["snap_to_guides"] is True
+        assert len(data["guides"]) == 2
+
+    def test_deserialize(self):
+        """Test deserialization"""
+        snap = SnappingSystem()
+
+        data = {
+            "snap_threshold_mm": 12.0,
+            "grid_size_mm": 20.0,
+            "snap_to_grid": True,
+            "snap_to_edges": False,
+            "snap_to_guides": False,
+            "guides": [{"position": 75.0, "orientation": "vertical"}, {"position": 125.0, "orientation": "horizontal"}],
+        }
+
+        snap.deserialize(data)
+
+        assert snap.snap_threshold_mm == 12.0
+        assert snap.grid_size_mm == 20.0
+        assert snap.snap_to_grid is True
+        assert snap.snap_to_edges is False
+        assert snap.snap_to_guides is False
+        assert len(snap.guides) == 2
+        assert snap.guides[0].position == 75.0
+        assert snap.guides[1].orientation == "horizontal"
+
+    def test_serialize_deserialize_roundtrip(self):
+        """Test serialize/deserialize roundtrip"""
+        original = SnappingSystem(snap_threshold_mm=7.5)
+        original.grid_size_mm = 12.5
+        original.snap_to_grid = True
+        original.add_guide(33.0, "vertical")
+        original.add_guide(66.0, "horizontal")
+
+        data = original.serialize()
+
+        restored = SnappingSystem()
+        restored.deserialize(data)
+
+        assert restored.snap_threshold_mm == original.snap_threshold_mm
+        assert restored.grid_size_mm == original.grid_size_mm
+        assert restored.snap_to_grid == original.snap_to_grid
+        assert restored.snap_to_edges == original.snap_to_edges
+        assert restored.snap_to_guides == original.snap_to_guides
+        assert len(restored.guides) == len(original.guides)
+
+    def test_deserialize_defaults(self):
+        """Test deserialization with missing fields uses defaults"""
+        snap = SnappingSystem()
+        snap.deserialize({})
+
+        assert snap.snap_threshold_mm == 5.0
+        assert snap.grid_size_mm == 10.0
+        assert snap.snap_to_grid is False
+        assert snap.snap_to_edges is True
+        assert snap.snap_to_guides is True
+        assert snap.guides == []
diff --git a/tests/test_template_manager.py b/tests/test_template_manager.py
index 5c015d4..d110522 100755
--- a/tests/test_template_manager.py
+++ b/tests/test_template_manager.py
@@ -25,11 +25,7 @@ class TestTemplate:
 
     def test_initialization_with_parameters(self):
         """Test Template initialization with custom parameters"""
-        template = Template(
-            name="My Template",
-            description="Test template",
-            page_size_mm=(200, 280)
-        )
+        template = Template(name="My Template", description="Test template", page_size_mm=(200, 280))
         assert template.name == "My Template"
         assert template.description == "Test template"
         assert template.page_size_mm == (200, 280)
@@ -38,7 +34,7 @@ class TestTemplate:
         """Test adding elements to template"""
         template = Template()
         placeholder = PlaceholderData(x=10, y=20, width=100, height=50)
-        
+
         template.add_element(placeholder)
         assert len(template.elements) == 1
         assert template.elements[0] == placeholder
@@ -48,10 +44,10 @@ class TestTemplate:
         template = Template()
         elem1 = PlaceholderData(x=10, y=20, width=100, height=50)
         elem2 = TextBoxData(text_content="Test", x=30, y=40, width=150, height=60)
-        
+
         template.add_element(elem1)
         template.add_element(elem2)
-        
+
         assert len(template.elements) == 2
         assert elem1 in template.elements
         assert elem2 in template.elements
@@ -61,9 +57,9 @@ class TestTemplate:
         template = Template(name="Test", description="Desc", page_size_mm=(200, 280))
         placeholder = PlaceholderData(x=10, y=20, width=100, height=50)
         template.add_element(placeholder)
-        
+
         data = template.to_dict()
-        
+
         assert data["name"] == "Test"
         assert data["description"] == "Desc"
         assert data["page_size_mm"] == (200, 280)
@@ -77,23 +73,13 @@ class TestTemplate:
             "description": "Test description",
             "page_size_mm": [220, 300],
             "elements": [
-                {
-                    "type": "placeholder",
-                    "position": (50, 60),
-                    "size": (120, 80),
-                    "placeholder_type": "image"
-                },
-                {
-                    "type": "textbox",
-                    "position": (70, 90),
-                    "size": (140, 100),
-                    "text_content": "Test text"
-                }
-            ]
+                {"type": "placeholder", "position": (50, 60), "size": (120, 80), "placeholder_type": "image"},
+                {"type": "textbox", "position": (70, 90), "size": (140, 100), "text_content": "Test text"},
+            ],
         }
-        
+
         template = Template.from_dict(data)
-        
+
         assert template.name == "Loaded Template"
         assert template.description == "Test description"
         assert template.page_size_mm == (220, 300)
@@ -107,12 +93,12 @@ class TestTemplate:
             "name": "Test",
             "elements": [
                 {"type": "image", "position": (10, 20), "size": (100, 50)},
-                {"type": "placeholder", "position": (30, 40), "size": (120, 60)}
-            ]
+                {"type": "placeholder", "position": (30, 40), "size": (120, 60)},
+            ],
         }
-        
+
         template = Template.from_dict(data)
-        
+
         # Should only have the placeholder, not the image
         assert len(template.elements) == 1
         assert isinstance(template.elements[0], PlaceholderData)
@@ -122,15 +108,15 @@ class TestTemplate:
         template = Template(name="Save Test", description="Test save")
         placeholder = PlaceholderData(x=10, y=20, width=100, height=50)
         template.add_element(placeholder)
-        
+
         file_path = Path(temp_dir) / "test_template.json"
         template.save_to_file(str(file_path))
-        
+
         # Verify file was created
         assert file_path.exists()
-        
+
         # Verify content
-        with open(file_path, 'r') as f:
+        with open(file_path, "r") as f:
             data = json.load(f)
         assert data["name"] == "Save Test"
         assert data["description"] == "Test save"
@@ -142,23 +128,16 @@ class TestTemplate:
             "name": "Load Test",
             "description": "Test load",
             "page_size_mm": [210, 297],
-            "elements": [
-                {
-                    "type": "placeholder",
-                    "position": (10, 20),
-                    "size": (100, 50),
-                    "placeholder_type": "image"
-                }
-            ]
+            "elements": [{"type": "placeholder", "position": (10, 20), "size": (100, 50), "placeholder_type": "image"}],
         }
-        
+
         file_path = Path(temp_dir) / "load_test.json"
-        with open(file_path, 'w') as f:
+        with open(file_path, "w") as f:
             json.dump(data, f)
-        
+
         # Load template
         template = Template.load_from_file(str(file_path))
-        
+
         assert template.name == "Load Test"
         assert template.description == "Test load"
         assert len(template.elements) == 1
@@ -177,7 +156,7 @@ class TestTemplateManager:
         """Test getting templates directory"""
         manager = TemplateManager()
         templates_dir = manager._get_templates_directory()
-        
+
         assert templates_dir.name == "templates"
         assert ".pyphotoalbum" in str(templates_dir)
 
@@ -185,7 +164,7 @@ class TestTemplateManager:
         """Test getting built-in templates directory"""
         manager = TemplateManager()
         builtin_dir = manager._get_builtin_templates_directory()
-        
+
         assert builtin_dir.name == "templates"
         assert "pyPhotoAlbum" in str(builtin_dir)
 
@@ -196,11 +175,11 @@ class TestTemplateManager:
         builtin_dir = tmp_path / "builtin_templates"
         user_dir.mkdir()
         builtin_dir.mkdir()
-        
+
         manager = TemplateManager()
-        monkeypatch.setattr(manager, 'templates_dir', user_dir)
-        monkeypatch.setattr(manager, '_get_builtin_templates_directory', lambda: builtin_dir)
-        
+        monkeypatch.setattr(manager, "templates_dir", user_dir)
+        monkeypatch.setattr(manager, "_get_builtin_templates_directory", lambda: builtin_dir)
+
         templates = manager.list_templates()
         assert templates == []
 
@@ -210,21 +189,21 @@ class TestTemplateManager:
         builtin_dir = tmp_path / "builtin_templates"
         user_dir.mkdir()
         builtin_dir.mkdir()
-        
+
         # Create user template
         user_template = user_dir / "My_Template.json"
         user_template.write_text('{"name": "My Template"}')
-        
+
         # Create built-in template
         builtin_template = builtin_dir / "Grid_2x2.json"
         builtin_template.write_text('{"name": "Grid 2x2"}')
-        
+
         manager = TemplateManager()
-        monkeypatch.setattr(manager, 'templates_dir', user_dir)
-        monkeypatch.setattr(manager, '_get_builtin_templates_directory', lambda: builtin_dir)
-        
+        monkeypatch.setattr(manager, "templates_dir", user_dir)
+        monkeypatch.setattr(manager, "_get_builtin_templates_directory", lambda: builtin_dir)
+
         templates = manager.list_templates()
-        
+
         assert "[Built-in] Grid_2x2" in templates
         assert "My_Template" in templates
         assert len(templates) == 2
@@ -233,13 +212,13 @@ class TestTemplateManager:
         """Test saving a template"""
         user_dir = tmp_path / "user_templates"
         user_dir.mkdir()
-        
+
         manager = TemplateManager()
-        monkeypatch.setattr(manager, 'templates_dir', user_dir)
-        
+        monkeypatch.setattr(manager, "templates_dir", user_dir)
+
         template = Template(name="Test Template")
         manager.save_template(template)
-        
+
         # Verify file was created
         template_file = user_dir / "Test Template.json"
         assert template_file.exists()
@@ -248,16 +227,16 @@ class TestTemplateManager:
         """Test loading a user template"""
         user_dir = tmp_path / "user_templates"
         user_dir.mkdir()
-        
+
         # Create template file
         data = {"name": "User Template", "description": "Test", "page_size_mm": [210, 297], "elements": []}
         template_file = user_dir / "User Template.json"
-        with open(template_file, 'w') as f:
+        with open(template_file, "w") as f:
             json.dump(data, f)
-        
+
         manager = TemplateManager()
-        monkeypatch.setattr(manager, 'templates_dir', user_dir)
-        
+        monkeypatch.setattr(manager, "templates_dir", user_dir)
+
         template = manager.load_template("User Template")
         assert template.name == "User Template"
 
@@ -265,16 +244,16 @@ class TestTemplateManager:
         """Test loading a built-in template"""
         builtin_dir = tmp_path / "builtin_templates"
         builtin_dir.mkdir()
-        
+
         # Create built-in template file
         data = {"name": "Grid 2x2", "description": "Built-in grid", "page_size_mm": [210, 297], "elements": []}
         template_file = builtin_dir / "Grid 2x2.json"
-        with open(template_file, 'w') as f:
+        with open(template_file, "w") as f:
             json.dump(data, f)
-        
+
         manager = TemplateManager()
-        monkeypatch.setattr(manager, '_get_builtin_templates_directory', lambda: builtin_dir)
-        
+        monkeypatch.setattr(manager, "_get_builtin_templates_directory", lambda: builtin_dir)
+
         template = manager.load_template("[Built-in] Grid 2x2")
         assert template.name == "Grid 2x2"
 
@@ -282,10 +261,10 @@ class TestTemplateManager:
         """Test loading non-existent template raises error"""
         user_dir = tmp_path / "user_templates"
         user_dir.mkdir()
-        
+
         manager = TemplateManager()
-        monkeypatch.setattr(manager, 'templates_dir', user_dir)
-        
+        monkeypatch.setattr(manager, "templates_dir", user_dir)
+
         with pytest.raises(FileNotFoundError):
             manager.load_template("NonExistent")
 
@@ -293,21 +272,21 @@ class TestTemplateManager:
         """Test deleting a user template"""
         user_dir = tmp_path / "user_templates"
         user_dir.mkdir()
-        
+
         # Create template file
         template_file = user_dir / "DeleteMe.json"
         template_file.write_text('{"name": "DeleteMe"}')
-        
+
         manager = TemplateManager()
-        monkeypatch.setattr(manager, 'templates_dir', user_dir)
-        
+        monkeypatch.setattr(manager, "templates_dir", user_dir)
+
         manager.delete_template("DeleteMe")
         assert not template_file.exists()
 
     def test_delete_builtin_template_raises_error(self):
         """Test deleting built-in template raises error"""
         manager = TemplateManager()
-        
+
         with pytest.raises(PermissionError):
             manager.delete_template("[Built-in] Grid_2x2")
 
@@ -318,25 +297,21 @@ class TestTemplateManager:
         img = ImageData(image_path="test.jpg", x=10, y=20, width=100, height=50)
         text = TextBoxData(text_content="Test", x=30, y=40, width=150, height=60)
         placeholder = PlaceholderData(x=50, y=60, width=120, height=70)
-        
+
         layout.add_element(img)
         layout.add_element(text)
         layout.add_element(placeholder)
-        
+
         page = Page(layout=layout, page_number=1)
-        
+
         # Create template
         manager = TemplateManager()
-        template = manager.create_template_from_page(
-            page,
-            name="Test Template",
-            description="Created from page"
-        )
-        
+        template = manager.create_template_from_page(page, name="Test Template", description="Created from page")
+
         assert template.name == "Test Template"
         assert template.description == "Created from page"
         assert len(template.elements) == 3
-        
+
         # Image should be converted to placeholder
         assert isinstance(template.elements[0], PlaceholderData)
         assert isinstance(template.elements[1], TextBoxData)
@@ -352,10 +327,7 @@ class TestTemplateManager:
 
         # Scale to 400x400 (2x scale) - results in pixels at 300 DPI
         scaled = manager.scale_template_elements(
-            elements,
-            from_size=(200, 200),
-            to_size=(400, 400),
-            scale_mode="proportional"
+            elements, from_size=(200, 200), to_size=(400, 400), scale_mode="proportional"
         )
 
         assert len(scaled) == 1
@@ -379,10 +351,7 @@ class TestTemplateManager:
 
         # Scale to 400x200 (2x width, 1x height) - results in pixels at 300 DPI
         scaled = manager.scale_template_elements(
-            elements,
-            from_size=(200, 200),
-            to_size=(400, 200),
-            scale_mode="stretch"
+            elements, from_size=(200, 200), to_size=(400, 200), scale_mode="stretch"
         )
 
         assert len(scaled) == 1
@@ -403,10 +372,7 @@ class TestTemplateManager:
 
         # Center in larger space without scaling - results in pixels at 300 DPI
         scaled = manager.scale_template_elements(
-            elements,
-            from_size=(200, 200),
-            to_size=(400, 400),
-            scale_mode="center"
+            elements, from_size=(200, 200), to_size=(400, 400), scale_mode="center"
         )
 
         assert len(scaled) == 1
@@ -422,19 +388,16 @@ class TestTemplateManager:
     def test_scale_template_preserves_properties(self):
         """Test that scaling preserves element properties"""
         manager = TemplateManager()
-        
+
         elem = PlaceholderData(x=50, y=50, width=100, height=100)
         elem.rotation = 45
         elem.z_index = 5
         elem.placeholder_type = "image"
-        
+
         scaled = manager.scale_template_elements(
-            [elem],
-            from_size=(200, 200),
-            to_size=(400, 400),
-            scale_mode="proportional"
+            [elem], from_size=(200, 200), to_size=(400, 400), scale_mode="proportional"
         )
-        
+
         assert scaled[0].rotation == 45
         assert scaled[0].z_index == 5
         assert scaled[0].placeholder_type == "image"
@@ -442,19 +405,19 @@ class TestTemplateManager:
     def test_apply_template_to_page_replace(self):
         """Test applying template with replace mode"""
         manager = TemplateManager()
-        
+
         # Create template
         template = Template(page_size_mm=(200, 200))
         template.add_element(PlaceholderData(x=10, y=20, width=80, height=60))
-        
+
         # Create page with existing content
         layout = PageLayout(width=200, height=200)
         layout.add_element(ImageData(x=100, y=100, width=50, height=50))
         page = Page(layout=layout, page_number=1)
-        
+
         # Apply template
         manager.apply_template_to_page(template, page, mode="replace")
-        
+
         # Page should have only template elements
         assert len(page.layout.elements) == 1
         assert isinstance(page.layout.elements[0], PlaceholderData)
@@ -462,21 +425,21 @@ class TestTemplateManager:
     def test_apply_template_to_page_reflow(self):
         """Test applying template with reflow mode"""
         manager = TemplateManager()
-        
+
         # Create template with 2 placeholders
         template = Template(page_size_mm=(200, 200))
         template.add_element(PlaceholderData(x=10, y=20, width=80, height=60))
         template.add_element(PlaceholderData(x=100, y=100, width=80, height=60))
-        
+
         # Create page with 1 image
         layout = PageLayout(width=200, height=200)
         img = ImageData(image_path="test.jpg", x=50, y=50, width=50, height=50)
         layout.add_element(img)
         page = Page(layout=layout, page_number=1)
-        
+
         # Apply template with reflow
         manager.apply_template_to_page(template, page, mode="reflow")
-        
+
         # Should have 1 image (reflowed) + 1 placeholder
         assert len(page.layout.elements) == 2
         # First should be the reflowed image
@@ -487,14 +450,14 @@ class TestTemplateManager:
     def test_create_page_from_template_default_size(self):
         """Test creating page from template with default size"""
         manager = TemplateManager()
-        
+
         # Create template
         template = Template(page_size_mm=(210, 297))
         template.add_element(PlaceholderData(x=10, y=20, width=100, height=50))
-        
+
         # Create page
         page = manager.create_page_from_template(template, page_number=5)
-        
+
         assert page.page_number == 5
         assert page.layout.size == (210, 297)
         assert len(page.layout.elements) == 1
@@ -510,11 +473,7 @@ class TestTemplateManager:
 
         # Create page at 400x400 with 0% margin for exact 2x scaling
         page = manager.create_page_from_template(
-            template,
-            page_number=1,
-            target_size_mm=(400, 400),
-            scale_mode="proportional",
-            margin_percent=0.0
+            template, page_number=1, target_size_mm=(400, 400), scale_mode="proportional", margin_percent=0.0
         )
 
         assert page.layout.size == (400, 400)
@@ -529,24 +488,14 @@ class TestTemplateManager:
     def test_scale_with_textbox_preserves_font_settings(self):
         """Test that scaling preserves text box font settings"""
         manager = TemplateManager()
-        
+
         font_settings = {"family": "Arial", "size": 12, "color": (0, 0, 0)}
-        text = TextBoxData(
-            text_content="Test",
-            font_settings=font_settings,
-            x=50,
-            y=50,
-            width=100,
-            height=50
-        )
-        
+        text = TextBoxData(text_content="Test", font_settings=font_settings, x=50, y=50, width=100, height=50)
+
         scaled = manager.scale_template_elements(
-            [text],
-            from_size=(200, 200),
-            to_size=(400, 400),
-            scale_mode="proportional"
+            [text], from_size=(200, 200), to_size=(400, 400), scale_mode="proportional"
         )
-        
+
         assert scaled[0].text_content == "Test"
         assert scaled[0].font_settings == font_settings
         assert scaled[0].alignment == text.alignment
@@ -567,12 +516,7 @@ class TestTemplateManager:
         layout = PageLayout(width=210, height=210)
         page = Page(layout=layout, page_number=1)
 
-        manager.apply_template_to_page(
-            template, page,
-            mode="replace",
-            scale_mode="stretch",
-            margin_percent=2.5
-        )
+        manager.apply_template_to_page(template, page, mode="replace", scale_mode="stretch", margin_percent=2.5)
 
         # With 2.5% margin on 210mm page: margin = 5.25mm, content area = 199.5mm
         # Template is 200mm, so scale = 199.5 / 200 = 0.9975
@@ -615,12 +559,7 @@ class TestTemplateManager:
         layout = PageLayout(width=210, height=297)
         page = Page(layout=layout, page_number=1)
 
-        manager.apply_template_to_page(
-            template, page,
-            mode="replace",
-            scale_mode="stretch",
-            margin_percent=2.5
-        )
+        manager.apply_template_to_page(template, page, mode="replace", scale_mode="stretch", margin_percent=2.5)
 
         # With 2.5% margin: x_margin = 5.25mm, y_margin = 7.425mm
         # Content area: 199.5 x 282.15mm
@@ -661,12 +600,7 @@ class TestTemplateManager:
         layout = PageLayout(width=210, height=210)
         page = Page(layout=layout, page_number=1)
 
-        manager.apply_template_to_page(
-            template, page,
-            mode="replace",
-            scale_mode="stretch",
-            margin_percent=0.0
-        )
+        manager.apply_template_to_page(template, page, mode="replace", scale_mode="stretch", margin_percent=0.0)
 
         # With 0% margin: scale = 210/200 = 1.05, offset = 0
         # Results are converted to pixels at 300 DPI
@@ -681,12 +615,7 @@ class TestTemplateManager:
         layout2 = PageLayout(width=210, height=210)
         page2 = Page(layout=layout2, page_number=1)
 
-        manager.apply_template_to_page(
-            template, page2,
-            mode="replace",
-            scale_mode="stretch",
-            margin_percent=5.0
-        )
+        manager.apply_template_to_page(template, page2, mode="replace", scale_mode="stretch", margin_percent=5.0)
 
         # With 5% margin: margin = 10.5mm, content = 189mm, scale = 189/200 = 0.945
         # Results are converted to pixels at 300 DPI
@@ -710,12 +639,7 @@ class TestTemplateManager:
         layout = PageLayout(width=210, height=297)
         page = Page(layout=layout, page_number=1)
 
-        manager.apply_template_to_page(
-            template, page,
-            mode="replace",
-            scale_mode="proportional",
-            margin_percent=2.5
-        )
+        manager.apply_template_to_page(template, page, mode="replace", scale_mode="proportional", margin_percent=2.5)
 
         # With proportional mode on 210x297 page:
         # Content area: 199.5 x 282.15mm
@@ -750,22 +674,22 @@ class TestTemplateManager:
 
         # Add various elements with specific sizes (in pixels)
         # Using pixel positions that correspond to reasonable mm values
-        img1 = ImageData(image_path="test1.jpg", x=10*mm_to_px, y=20*mm_to_px, width=100*mm_to_px, height=75*mm_to_px)
-        img2 = ImageData(image_path="test2.jpg", x=120*mm_to_px, y=30*mm_to_px, width=80*mm_to_px, height=60*mm_to_px)
+        img1 = ImageData(
+            image_path="test1.jpg", x=10 * mm_to_px, y=20 * mm_to_px, width=100 * mm_to_px, height=75 * mm_to_px
+        )
+        img2 = ImageData(
+            image_path="test2.jpg", x=120 * mm_to_px, y=30 * mm_to_px, width=80 * mm_to_px, height=60 * mm_to_px
+        )
         text1 = TextBoxData(
             text_content="Test Text",
-            x=30*mm_to_px,
-            y=150*mm_to_px,
-            width=150*mm_to_px,
-            height=40*mm_to_px,
-            font_settings={"family": "Arial", "size": 12}
+            x=30 * mm_to_px,
+            y=150 * mm_to_px,
+            width=150 * mm_to_px,
+            height=40 * mm_to_px,
+            font_settings={"family": "Arial", "size": 12},
         )
         placeholder1 = PlaceholderData(
-            placeholder_type="image",
-            x=50*mm_to_px,
-            y=220*mm_to_px,
-            width=110*mm_to_px,
-            height=60*mm_to_px
+            placeholder_type="image", x=50 * mm_to_px, y=220 * mm_to_px, width=110 * mm_to_px, height=60 * mm_to_px
         )
 
         layout.add_element(img1)
@@ -778,19 +702,19 @@ class TestTemplateManager:
         # Store original element data
         original_elements_data = []
         for elem in original_page.layout.elements:
-            original_elements_data.append({
-                'type': type(elem).__name__,
-                'position': elem.position,
-                'size': elem.size,
-                'rotation': elem.rotation,
-                'z_index': elem.z_index
-            })
+            original_elements_data.append(
+                {
+                    "type": type(elem).__name__,
+                    "position": elem.position,
+                    "size": elem.size,
+                    "rotation": elem.rotation,
+                    "z_index": elem.z_index,
+                }
+            )
 
         # Create a template from the page
         template = manager.create_template_from_page(
-            original_page,
-            name="Roundtrip Test Template",
-            description="Testing size preservation"
+            original_page, name="Roundtrip Test Template", description="Testing size preservation"
         )
 
         # Create a new page with the same size
@@ -800,11 +724,7 @@ class TestTemplateManager:
         # Apply the template to the new page with no margins and proportional scaling
         # This should result in identical sizes since page sizes match
         manager.apply_template_to_page(
-            template,
-            new_page,
-            mode="replace",
-            scale_mode="proportional",
-            margin_percent=0.0
+            template, new_page, mode="replace", scale_mode="proportional", margin_percent=0.0
         )
 
         # Verify we have the same number of elements
diff --git a/tests/test_view_ops_mixin.py b/tests/test_view_ops_mixin.py
index afa3170..ec75a11 100755
--- a/tests/test_view_ops_mixin.py
+++ b/tests/test_view_ops_mixin.py
@@ -33,7 +33,7 @@ class TestViewWindow(ViewOperationsMixin, QMainWindow):
         self._status_message = None
 
     def get_current_page(self):
-        if hasattr(self, '_current_page'):
+        if hasattr(self, "_current_page"):
             return self._current_page
         return None
 
@@ -289,8 +289,8 @@ class TestGuideOperations:
 
         layout = PageLayout()
         # Add some guides
-        layout.snapping_system.add_guide(100, 'vertical')
-        layout.snapping_system.add_guide(150, 'horizontal')
+        layout.snapping_system.add_guide(100, "vertical")
+        layout.snapping_system.add_guide(150, "horizontal")
         page = Mock()
         page.layout = layout
         window._current_page = page
@@ -357,7 +357,7 @@ class TestGridSettingsDialog:
         mock_dialog = Mock(spec=QDialog)
         mock_dialog.exec.return_value = QDialog.DialogCode.Rejected
 
-        with patch('PyQt6.QtWidgets.QDialog', return_value=mock_dialog):
+        with patch("PyQt6.QtWidgets.QDialog", return_value=mock_dialog):
             window.set_grid_size()
 
             # Dialog should have been created and exec called
@@ -426,7 +426,7 @@ class TestLayoutTabDelegation:
         mock_dialog = Mock(spec=QDialog)
         mock_dialog.exec.return_value = QDialog.DialogCode.Rejected
 
-        with patch('PyQt6.QtWidgets.QDialog', return_value=mock_dialog):
+        with patch("PyQt6.QtWidgets.QDialog", return_value=mock_dialog):
             window.layout_set_grid_size()
 
             # Verify method was called (dialog creation attempted)
diff --git a/tests/test_viewport_mixin.py b/tests/test_viewport_mixin.py
index 1a8c1de..26dcc18 100755
--- a/tests/test_viewport_mixin.py
+++ b/tests/test_viewport_mixin.py
@@ -14,6 +14,7 @@ from pyPhotoAlbum.page_layout import PageLayout
 # Create a minimal test widget class
 class TestViewportWidget(ViewportMixin, QOpenGLWidget):
     """Test widget combining ViewportMixin with QOpenGLWidget"""
+
     pass
 
 
@@ -90,10 +91,7 @@ class TestViewportCalculations:
         mock_window.project.working_dpi = 96
 
         # A4 page: 210mm x 297mm
-        page = Page(
-            layout=PageLayout(width=210, height=297),
-            page_number=1
-        )
+        page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         mock_window.project.pages = [page]
 
         widget.window = Mock(return_value=mock_window)
@@ -120,10 +118,7 @@ class TestViewportCalculations:
         mock_window.project = Project(name="Test")
         mock_window.project.working_dpi = 96
 
-        page = Page(
-            layout=PageLayout(width=210, height=297),
-            page_number=1
-        )
+        page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         mock_window.project.pages = [page]
 
         widget.window = Mock(return_value=mock_window)
@@ -144,10 +139,7 @@ class TestViewportCalculations:
         mock_window.project = Project(name="Test")
         mock_window.project.working_dpi = 96
 
-        page = Page(
-            layout=PageLayout(width=210, height=297),
-            page_number=1
-        )
+        page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         mock_window.project.pages = [page]
 
         widget.window = Mock(return_value=mock_window)
@@ -167,10 +159,7 @@ class TestViewportCalculations:
         mock_window.project = Project(name="Test")
         mock_window.project.working_dpi = 300  # High DPI
 
-        page = Page(
-            layout=PageLayout(width=210, height=297),
-            page_number=1
-        )
+        page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         mock_window.project.pages = [page]
 
         widget.window = Mock(return_value=mock_window)
@@ -226,10 +215,7 @@ class TestViewportCentering:
         mock_window.project.working_dpi = 96
 
         # A4 page: 210mm x 297mm
-        page = Page(
-            layout=PageLayout(width=210, height=297),
-            page_number=1
-        )
+        page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         mock_window.project.pages = [page]
 
         widget.window = Mock(return_value=mock_window)
@@ -262,10 +248,7 @@ class TestViewportCentering:
         mock_window.project.working_dpi = 96
 
         # A4 page: 210mm x 297mm
-        page = Page(
-            layout=PageLayout(width=210, height=297),
-            page_number=1
-        )
+        page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         mock_window.project.pages = [page]
 
         widget.window = Mock(return_value=mock_window)
@@ -298,10 +281,7 @@ class TestViewportCentering:
         mock_window.project.working_dpi = 96
 
         # 6x4 inch photo: 152.4mm x 101.6mm
-        page = Page(
-            layout=PageLayout(width=152.4, height=101.6),
-            page_number=1
-        )
+        page = Page(layout=PageLayout(width=152.4, height=101.6), page_number=1)
         mock_window.project.pages = [page]
 
         widget.window = Mock(return_value=mock_window)
@@ -324,10 +304,7 @@ class TestViewportCentering:
         mock_window.project.working_dpi = 96
 
         # A4 page: 210mm x 297mm
-        page = Page(
-            layout=PageLayout(width=210, height=297),
-            page_number=1
-        )
+        page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         mock_window.project.pages = [page]
 
         widget.window = Mock(return_value=mock_window)
@@ -337,7 +314,7 @@ class TestViewportCentering:
 
         # Large window should have large positive offsets
         assert offset[0] > 1000  # Lots of horizontal space
-        assert offset[1] > 400   # Lots of vertical space
+        assert offset[1] > 400  # Lots of vertical space
 
     def test_calculate_center_pan_offset_different_zoom_levels(self, qtbot):
         """Test that different zoom levels produce different offsets"""
@@ -349,10 +326,7 @@ class TestViewportCentering:
         mock_window.project = Project(name="Test")
         mock_window.project.working_dpi = 96
 
-        page = Page(
-            layout=PageLayout(width=210, height=297),
-            page_number=1
-        )
+        page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         mock_window.project.pages = [page]
 
         widget.window = Mock(return_value=mock_window)
@@ -378,10 +352,7 @@ class TestViewportCentering:
         mock_window = Mock()
         mock_window.project = Project(name="Test")
 
-        page = Page(
-            layout=PageLayout(width=210, height=297),
-            page_number=1
-        )
+        page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         mock_window.project.pages = [page]
 
         # Test at 96 DPI
@@ -412,10 +383,7 @@ class TestViewportResizing:
         mock_window.project = Project(name="Test")
         mock_window.project.working_dpi = 96
 
-        page = Page(
-            layout=PageLayout(width=210, height=297),
-            page_number=1
-        )
+        page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         mock_window.project.pages = [page]
         widget.window = Mock(return_value=mock_window)
 
@@ -424,14 +392,14 @@ class TestViewportResizing:
         widget.zoom_level = 0.5
 
         # Get initial centered offset for 1000x800
-        with patch.object(widget, 'width', return_value=1000):
-            with patch.object(widget, 'height', return_value=800):
+        with patch.object(widget, "width", return_value=1000):
+            with patch.object(widget, "height", return_value=800):
                 initial_offset = list(widget._calculate_center_pan_offset(0.5))
 
         # Trigger a resize to larger window (1200x900)
         # Mock the widget's dimensions during resizeGL
-        with patch.object(widget, 'width', return_value=1200):
-            with patch.object(widget, 'height', return_value=900):
+        with patch.object(widget, "width", return_value=1200):
+            with patch.object(widget, "height", return_value=900):
                 widget.resizeGL(1200, 900)
                 new_offset = widget.pan_offset
 
@@ -466,10 +434,7 @@ class TestViewportResizing:
         mock_window.project = Project(name="Test")
         mock_window.project.working_dpi = 96
 
-        page = Page(
-            layout=PageLayout(width=210, height=297),
-            page_number=1
-        )
+        page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         mock_window.project.pages = [page]
         widget.window = Mock(return_value=mock_window)
 
@@ -493,10 +458,7 @@ class TestViewportResizing:
         mock_window.project = Project(name="Test")
         mock_window.project.working_dpi = 96
 
-        page = Page(
-            layout=PageLayout(width=210, height=297),
-            page_number=1
-        )
+        page = Page(layout=PageLayout(width=210, height=297), page_number=1)
         mock_window.project.pages = [page]
         widget.window = Mock(return_value=mock_window)
 
@@ -527,7 +489,7 @@ class TestViewportOpenGL:
         qtbot.addWidget(widget)
 
         # Just verify the method exists and is callable
-        assert hasattr(widget, 'initializeGL')
+        assert hasattr(widget, "initializeGL")
         assert callable(widget.initializeGL)
 
     def test_resizeGL_is_callable(self, qtbot):
@@ -535,5 +497,5 @@ class TestViewportOpenGL:
         widget = TestViewportWidget()
         qtbot.addWidget(widget)
 
-        assert hasattr(widget, 'resizeGL')
+        assert hasattr(widget, "resizeGL")
         assert callable(widget.resizeGL)
diff --git a/tests/test_zorder.py b/tests/test_zorder.py
index cb0b3b9..e4cc0b4 100755
--- a/tests/test_zorder.py
+++ b/tests/test_zorder.py
@@ -10,35 +10,35 @@ from pyPhotoAlbum.commands import ChangeZOrderCommand, CommandHistory
 
 class TestZOrderBasics:
     """Tests for basic z-order functionality"""
-    
+
     def test_list_order_is_render_order(self):
         """Test that list order determines render order"""
         layout = PageLayout(width=210, height=297)
-        
+
         # Add elements in order
         elem1 = ImageData(x=10, y=10, width=50, height=50)
         elem2 = TextBoxData(x=20, y=20, width=50, height=50)
         elem3 = PlaceholderData(x=30, y=30, width=50, height=50)
-        
+
         layout.add_element(elem1)
         layout.add_element(elem2)
         layout.add_element(elem3)
-        
+
         # Verify order
         assert layout.elements[0] is elem1
         assert layout.elements[1] is elem2
         assert layout.elements[2] is elem3
-    
+
     def test_element_at_end_renders_on_top(self):
         """Test that element at end of list renders on top"""
         layout = PageLayout(width=210, height=297)
-        
+
         elem1 = ImageData(x=10, y=10)
         elem2 = ImageData(x=20, y=20)
-        
+
         layout.add_element(elem1)
         layout.add_element(elem2)
-        
+
         # elem2 should be last (on top)
         assert layout.elements[-1] is elem2
         assert layout.elements.index(elem2) > layout.elements.index(elem1)
@@ -46,133 +46,133 @@ class TestZOrderBasics:
 
 class TestChangeZOrderCommand:
     """Tests for ChangeZOrderCommand"""
-    
+
     def test_move_element_forward(self):
         """Test moving an element forward one position"""
         layout = PageLayout()
         elem1 = ImageData(x=10, y=10)
         elem2 = TextBoxData(x=20, y=20)
         elem3 = PlaceholderData(x=30, y=30)
-        
+
         layout.add_element(elem1)
         layout.add_element(elem2)
         layout.add_element(elem3)
-        
+
         # Move elem1 forward (swap with elem2)
         cmd = ChangeZOrderCommand(layout, elem1, old_index=0, new_index=1)
         cmd.execute()
-        
+
         assert layout.elements.index(elem1) == 1
         assert layout.elements.index(elem2) == 0
         assert layout.elements.index(elem3) == 2
-    
+
     def test_move_element_backward(self):
         """Test moving an element backward one position"""
         layout = PageLayout()
         elem1 = ImageData(x=10, y=10)
         elem2 = TextBoxData(x=20, y=20)
         elem3 = PlaceholderData(x=30, y=30)
-        
+
         layout.add_element(elem1)
         layout.add_element(elem2)
         layout.add_element(elem3)
-        
+
         # Move elem2 backward (swap with elem1)
         cmd = ChangeZOrderCommand(layout, elem2, old_index=1, new_index=0)
         cmd.execute()
-        
+
         assert layout.elements.index(elem2) == 0
         assert layout.elements.index(elem1) == 1
         assert layout.elements.index(elem3) == 2
-    
+
     def test_move_to_front(self):
         """Test moving an element to the front (end of list)"""
         layout = PageLayout()
         elem1 = ImageData(x=10, y=10)
         elem2 = TextBoxData(x=20, y=20)
         elem3 = PlaceholderData(x=30, y=30)
-        
+
         layout.add_element(elem1)
         layout.add_element(elem2)
         layout.add_element(elem3)
-        
+
         # Move elem1 to front
         cmd = ChangeZOrderCommand(layout, elem1, old_index=0, new_index=2)
         cmd.execute()
-        
+
         assert layout.elements[-1] is elem1
         assert layout.elements.index(elem1) == 2
-    
+
     def test_move_to_back(self):
         """Test moving an element to the back (start of list)"""
         layout = PageLayout()
         elem1 = ImageData(x=10, y=10)
         elem2 = TextBoxData(x=20, y=20)
         elem3 = PlaceholderData(x=30, y=30)
-        
+
         layout.add_element(elem1)
         layout.add_element(elem2)
         layout.add_element(elem3)
-        
+
         # Move elem3 to back
         cmd = ChangeZOrderCommand(layout, elem3, old_index=2, new_index=0)
         cmd.execute()
-        
+
         assert layout.elements[0] is elem3
         assert layout.elements.index(elem3) == 0
-    
+
     def test_undo_redo(self):
         """Test undo/redo functionality"""
         layout = PageLayout()
         elem1 = ImageData(x=10, y=10)
         elem2 = TextBoxData(x=20, y=20)
         elem3 = PlaceholderData(x=30, y=30)
-        
+
         layout.add_element(elem1)
         layout.add_element(elem2)
         layout.add_element(elem3)
-        
+
         original_order = list(layout.elements)
-        
+
         # Move elem1 forward
         cmd = ChangeZOrderCommand(layout, elem1, old_index=0, new_index=1)
         cmd.execute()
-        
+
         assert layout.elements.index(elem1) == 1
-        
+
         # Undo
         cmd.undo()
         assert layout.elements == original_order
-        
+
         # Redo
         cmd.redo()
         assert layout.elements.index(elem1) == 1
-    
+
     def test_command_with_history(self):
         """Test ChangeZOrderCommand with CommandHistory"""
         layout = PageLayout()
         history = CommandHistory()
-        
+
         elem1 = ImageData(x=10, y=10)
         elem2 = TextBoxData(x=20, y=20)
         elem3 = PlaceholderData(x=30, y=30)
-        
+
         layout.add_element(elem1)
         layout.add_element(elem2)
         layout.add_element(elem3)
-        
+
         # Execute command through history
         cmd = ChangeZOrderCommand(layout, elem1, old_index=0, new_index=2)
         history.execute(cmd)
-        
+
         assert layout.elements.index(elem1) == 2
         assert history.can_undo()
-        
+
         # Undo through history
         history.undo()
         assert layout.elements.index(elem1) == 0
         assert history.can_redo()
-        
+
         # Redo through history
         history.redo()
         assert layout.elements.index(elem1) == 2
@@ -180,72 +180,93 @@ class TestChangeZOrderCommand:
 
 class TestZOrderSerialization:
     """Tests for z-order serialization and deserialization"""
-    
+
     def test_serialize_preserves_order(self):
         """Test that serialization preserves element order"""
         layout = PageLayout()
         elem1 = ImageData(x=10, y=10, z_index=0)
         elem2 = TextBoxData(x=20, y=20, z_index=1)
         elem3 = PlaceholderData(x=30, y=30, z_index=2)
-        
+
         layout.add_element(elem1)
         layout.add_element(elem2)
         layout.add_element(elem3)
-        
+
         # Serialize
         data = layout.serialize()
-        
+
         # Elements should be in order
-        assert len(data['elements']) == 3
-        assert data['elements'][0]['type'] == 'image'
-        assert data['elements'][1]['type'] == 'textbox'
-        assert data['elements'][2]['type'] == 'placeholder'
-    
+        assert len(data["elements"]) == 3
+        assert data["elements"][0]["type"] == "image"
+        assert data["elements"][1]["type"] == "textbox"
+        assert data["elements"][2]["type"] == "placeholder"
+
     def test_deserialize_sorts_by_zindex(self):
         """Test that deserialization sorts by z_index for backward compatibility"""
         layout = PageLayout()
-        
+
         # Create data with z_index values out of order
         data = {
-            'size': (210, 297),
-            'base_width': 210,
-            'is_facing_page': False,
-            'background_color': (1.0, 1.0, 1.0),
-            'elements': [
-                {'type': 'image', 'position': (10, 10), 'size': (50, 50), 
-                 'rotation': 0, 'z_index': 2, 'image_path': '', 'crop_info': (0, 0, 1, 1)},
-                {'type': 'textbox', 'position': (20, 20), 'size': (50, 50), 
-                 'rotation': 0, 'z_index': 0, 'text_content': '', 
-                 'font_settings': {}, 'alignment': 'left'},
-                {'type': 'placeholder', 'position': (30, 30), 'size': (50, 50), 
-                 'rotation': 0, 'z_index': 1, 'placeholder_type': 'image', 'default_content': ''},
-            ]
+            "size": (210, 297),
+            "base_width": 210,
+            "is_facing_page": False,
+            "background_color": (1.0, 1.0, 1.0),
+            "elements": [
+                {
+                    "type": "image",
+                    "position": (10, 10),
+                    "size": (50, 50),
+                    "rotation": 0,
+                    "z_index": 2,
+                    "image_path": "",
+                    "crop_info": (0, 0, 1, 1),
+                },
+                {
+                    "type": "textbox",
+                    "position": (20, 20),
+                    "size": (50, 50),
+                    "rotation": 0,
+                    "z_index": 0,
+                    "text_content": "",
+                    "font_settings": {},
+                    "alignment": "left",
+                },
+                {
+                    "type": "placeholder",
+                    "position": (30, 30),
+                    "size": (50, 50),
+                    "rotation": 0,
+                    "z_index": 1,
+                    "placeholder_type": "image",
+                    "default_content": "",
+                },
+            ],
         }
-        
+
         layout.deserialize(data)
-        
+
         # Elements should be sorted by z_index
         assert len(layout.elements) == 3
         assert isinstance(layout.elements[0], TextBoxData)  # z_index=0
         assert isinstance(layout.elements[1], PlaceholderData)  # z_index=1
         assert isinstance(layout.elements[2], ImageData)  # z_index=2
-    
+
     def test_roundtrip_maintains_order(self):
         """Test that serialize/deserialize maintains element order"""
         layout1 = PageLayout()
         elem1 = ImageData(x=10, y=10, z_index=0)
         elem2 = TextBoxData(x=20, y=20, z_index=1)
         elem3 = PlaceholderData(x=30, y=30, z_index=2)
-        
+
         layout1.add_element(elem1)
         layout1.add_element(elem2)
         layout1.add_element(elem3)
-        
+
         # Serialize and deserialize
         data = layout1.serialize()
         layout2 = PageLayout()
         layout2.deserialize(data)
-        
+
         # Order should be maintained
         assert len(layout2.elements) == 3
         assert isinstance(layout2.elements[0], ImageData)
@@ -255,126 +276,126 @@ class TestZOrderSerialization:
 
 class TestZOrderEdgeCases:
     """Tests for z-order edge cases"""
-    
+
     def test_single_element(self):
         """Test operations with single element"""
         layout = PageLayout()
         elem = ImageData(x=10, y=10)
         layout.add_element(elem)
-        
+
         # Try to move forward (should stay at index 0)
         cmd = ChangeZOrderCommand(layout, elem, old_index=0, new_index=0)
         cmd.execute()
-        
+
         assert layout.elements.index(elem) == 0
-    
+
     def test_empty_list(self):
         """Test operations with empty list"""
         layout = PageLayout()
         assert len(layout.elements) == 0
-    
+
     def test_move_to_same_position(self):
         """Test moving element to its current position"""
         layout = PageLayout()
         elem1 = ImageData(x=10, y=10)
         elem2 = TextBoxData(x=20, y=20)
-        
+
         layout.add_element(elem1)
         layout.add_element(elem2)
-        
+
         # Move to same position
         cmd = ChangeZOrderCommand(layout, elem1, old_index=0, new_index=0)
         cmd.execute()
-        
+
         assert layout.elements.index(elem1) == 0
         assert layout.elements.index(elem2) == 1
-    
+
     def test_swap_adjacent_elements(self):
         """Test swapping two adjacent elements"""
         layout = PageLayout()
         elem1 = ImageData(x=10, y=10)
         elem2 = TextBoxData(x=20, y=20)
-        
+
         layout.add_element(elem1)
         layout.add_element(elem2)
-        
+
         # Swap by moving elem1 forward
         elements = layout.elements
         index1 = elements.index(elem1)
         index2 = elements.index(elem2)
         elements[index1], elements[index2] = elements[index2], elements[index1]
-        
+
         assert layout.elements[0] is elem2
         assert layout.elements[1] is elem1
-    
+
     def test_multiple_zorder_changes(self):
         """Test multiple z-order changes in sequence"""
         layout = PageLayout()
         history = CommandHistory()
-        
+
         elem1 = ImageData(x=10, y=10)
         elem2 = TextBoxData(x=20, y=20)
         elem3 = PlaceholderData(x=30, y=30)
-        
+
         layout.add_element(elem1)
         layout.add_element(elem2)
         layout.add_element(elem3)
-        
+
         # Move elem1 to front
         cmd1 = ChangeZOrderCommand(layout, elem1, old_index=0, new_index=2)
         history.execute(cmd1)
         assert layout.elements.index(elem1) == 2
-        
+
         # Move elem2 to front
         cmd2 = ChangeZOrderCommand(layout, elem2, old_index=0, new_index=2)
         history.execute(cmd2)
         assert layout.elements.index(elem2) == 2
-        
+
         # Undo both
         history.undo()
         assert layout.elements.index(elem2) == 0
-        
+
         history.undo()
         assert layout.elements.index(elem1) == 0
 
 
 class TestZOrderCommandSerialization:
     """Tests for ChangeZOrderCommand serialization"""
-    
+
     def test_serialize_command(self):
         """Test serializing a ChangeZOrderCommand"""
         layout = PageLayout()
         elem = ImageData(x=10, y=10)
         layout.add_element(elem)
-        
+
         cmd = ChangeZOrderCommand(layout, elem, old_index=0, new_index=1)
-        
+
         data = cmd.serialize()
-        
-        assert data['type'] == 'change_zorder'
-        assert data['old_index'] == 0
-        assert data['new_index'] == 1
-        assert 'element' in data
-    
+
+        assert data["type"] == "change_zorder"
+        assert data["old_index"] == 0
+        assert data["new_index"] == 1
+        assert "element" in data
+
     def test_deserialize_command(self):
         """Test deserializing a ChangeZOrderCommand"""
         data = {
-            'type': 'change_zorder',
-            'element': {
-                'type': 'image',
-                'position': (10, 10),
-                'size': (50, 50),
-                'rotation': 0,
-                'z_index': 0,
-                'image_path': '',
-                'crop_info': (0, 0, 1, 1)
+            "type": "change_zorder",
+            "element": {
+                "type": "image",
+                "position": (10, 10),
+                "size": (50, 50),
+                "rotation": 0,
+                "z_index": 0,
+                "image_path": "",
+                "crop_info": (0, 0, 1, 1),
             },
-            'old_index': 0,
-            'new_index': 1
+            "old_index": 0,
+            "new_index": 1,
         }
-        
+
         cmd = ChangeZOrderCommand.deserialize(data, None)
-        
+
         assert isinstance(cmd, ChangeZOrderCommand)
         assert cmd.old_index == 0
         assert cmd.new_index == 1
diff --git a/tests/test_zorder_ops_mixin.py b/tests/test_zorder_ops_mixin.py
index 9e71505..8b99950 100755
--- a/tests/test_zorder_ops_mixin.py
+++ b/tests/test_zorder_ops_mixin.py
@@ -34,7 +34,7 @@ class TestZOrderWindow(ZOrderOperationsMixin, QMainWindow):
 
     def get_current_page(self):
         """Return mock current page"""
-        if hasattr(self, '_current_page'):
+        if hasattr(self, "_current_page"):
             return self._current_page
         return None