Add optional background color to NavigationRailM3E and bump package versions to 0.3.4

packages/m3e_collection/pubspec.yaml

@@ -1,6 +1,6 @@
 name: m3e_collection
 description: Aggregated exports of all Material 3 Expressive components for Flutter.
-version: 0.3.3
+version: 0.3.4
 repository: https://github.com/EmilyMoonstone/material_3_expressive/tree/main/packages/m3e_collection
 issue_tracker: https://github.com/EmilyMonestone/material_3_expressive/issues
 
@@ -8,7 +8,7 @@ environment:
   sdk: ">=3.5.0 <4.0.0"
 
 dependencies:
-  app_bar_m3e: ^0.1.1
+  app_bar_m3e: ^0.1.2
   button_group_m3e: ^0.1.1
   button_m3e: ^0.1.1
   expressive_refresh: ^0.1.2
@@ -20,7 +20,7 @@ dependencies:
   m3e_design: ^0.2.1
   material_new_shapes: ^1.0.0
   navigation_bar_m3e: ^0.1.1
-  navigation_rail_m3e: ^0.3.3
+  navigation_rail_m3e: ^0.3.4
   progress_indicator_m3e: ^0.1.1
   slider_m3e: ^0.1.1
   split_button_m3e: ^0.2.1

packages/navigation_rail_m3e/lib/src/navigation_rail_m3e_widget.dart

@@ -30,6 +30,7 @@ class NavigationRailM3E extends StatefulWidget {
     this.scrollable = true,
     this.trailing,
     this.trailingAtBottom = true,
+    this.background,
   });
 
   /// Presentation type for the rail (collapsed or expanded or alwaysCollapsed or alwaysExpanded).
@@ -80,6 +81,10 @@ class NavigationRailM3E extends StatefulWidget {
   /// If false, [trailing] appears directly after the sections.
   final bool trailingAtBottom;
 
+  /// Optional background color for the rail. If null, falls back to
+  /// [NavigationRailTokensAdapter.containerColor] from the current theme.
+  final Color? background;
+
   @override
   State<NavigationRailM3E> createState() => _NavigationRailM3EState();
 }
@@ -464,7 +469,8 @@ class _NavigationRailM3EState extends State<NavigationRailM3E>
       duration: const Duration(milliseconds: 280),
       curve: Curves.easeOutCubic,
       width: width,
-      decoration: BoxDecoration(color: tokens.containerColor),
+      decoration:
+          BoxDecoration(color: widget.background ?? tokens.containerColor),
       child: LayoutBuilder(
         builder: (ctx, constraints) {
           final showLabels = _isExpanded && constraints.maxWidth >= 180;

packages/navigation_rail_m3e/lib/src/rail_tokens_adapter.dart

@@ -15,8 +15,7 @@ class NavigationRailTokensAdapter {
   /// Background color of the rail container.
   Color get containerColor {
     // Use surface container token if present, else fallback.
-    return _maybe(() => context.m3e.colors.surfaceContainer) ??
-        _cs.surfaceContainer;
+    return _maybe(() => context.m3e.colors.surface) ?? _cs.surface;
   }
 
   /// Background color of the active item indicator.

packages/navigation_rail_m3e/pubspec.yaml

@@ -1,6 +1,6 @@
 name: navigation_rail_m3e
 description: Material 3 Expressive navigation rail (collapsed & expanded) with modal/standard modes, badges, sections, and m3e_design token integration.
-version: 0.3.3
+version: 0.3.4
 homepage: https://github.com/EmilyMonestone/material_3_expressive
 repository: https://github.com/EmilyMoonstone/material_3_expressive/tree/main/packages/navigation_rail_m3e
 issue_tracker: https://github.com/EmilyMonestone/material_3_expressive/issues