fix: use GTK theme colors, translucent cards, focus confirm on keyboard

- Replace hardcoded colors with @theme_* variables for consistency
- Card backgrounds use alpha for subtle translucency over wallpaper
- Confirmation dialog grabs focus on "No" button for safe keyboard nav

src/moonset/panel.py

@@ -263,6 +263,9 @@ class PanelWindow(Gtk.ApplicationWindow):
         self._confirm_box.append(button_box)
         self._confirm_area.append(self._confirm_box)
 
+        # Focus the "No" button — safe default for keyboard navigation
+        no_btn.grab_focus()
+
     def _dismiss_confirm(self) -> None:
         """Remove the confirmation prompt."""
         if self._confirm_box is not None:

src/moonset/style.css

@@ -1,16 +1,16 @@
 /* ABOUTME: GTK4 CSS stylesheet for the Moonset power menu. */
-/* ABOUTME: Catppuccin Mocha theme with action buttons and confirmation styling. */
+/* ABOUTME: Uses GTK theme colors for consistency with the active desktop theme. */
 
 /* Main panel window background */
 window.panel {
-    background-color: #1a1a2e;
+    background-color: @theme_bg_color;
     background-size: cover;
     background-position: center;
 }
 
 /* Wallpaper-only window for secondary monitors */
 window.wallpaper {
-    background-color: #1a1a2e;
+    background-color: @theme_bg_color;
 }
 
 /* Action button — square card */
@@ -19,37 +19,37 @@ window.wallpaper {
     min-height: 120px;
     padding: 16px;
     border-radius: 16px;
-    background-color: alpha(white, 0.08);
-    color: white;
+    background-color: alpha(@theme_base_color, 0.55);
+    color: @theme_fg_color;
     border: none;
 }
 
 .action-button:hover {
-    background-color: alpha(white, 0.20);
+    background-color: alpha(@theme_base_color, 0.7);
 }
 
 /* Action icon inside button */
 .action-icon {
-    color: white;
+    color: @theme_fg_color;
 }
 
 /* Action label below icon */
 .action-label {
     font-size: 14px;
-    color: white;
+    color: @theme_unfocused_fg_color;
 }
 
 /* Confirmation box below action buttons */
 .confirm-box {
     padding: 16px 24px;
     border-radius: 12px;
-    background-color: alpha(white, 0.08);
+    background-color: @theme_base_color;
 }
 
 /* Confirmation prompt text */
 .confirm-label {
     font-size: 16px;
-    color: white;
+    color: @theme_fg_color;
     margin-bottom: 4px;
 }
 
@@ -57,31 +57,31 @@ window.wallpaper {
 .confirm-yes {
     padding: 8px 24px;
     border-radius: 8px;
-    background-color: #ff6b6b;
-    color: white;
+    background-color: @error_color;
+    color: @theme_bg_color;
     border: none;
     font-weight: bold;
 }
 
 .confirm-yes:hover {
-    background-color: #ff8787;
+    background-color: lighter(@error_color);
 }
 
 /* Confirm "No/Cancel" button */
 .confirm-no {
     padding: 8px 24px;
     border-radius: 8px;
-    background-color: alpha(white, 0.12);
-    color: white;
+    background-color: @theme_unfocused_bg_color;
+    color: @theme_fg_color;
     border: none;
 }
 
 .confirm-no:hover {
-    background-color: alpha(white, 0.25);
+    background-color: @theme_selected_bg_color;
 }
 
 /* Error message label */
 .error-label {
-    color: #ff6b6b;
+    color: @error_color;
     font-size: 14px;
 }