fix: 胶囊高度42px + 功能卡片白底 + 面板绿粉渐变 + 间距调整

health_app/lib/widgets/health_drawer.dart

@@ -415,6 +415,11 @@ class _NavigationSection extends StatelessWidget {
 
     return _Panel(
       title: '功能入口',
+      backgroundGradient: const LinearGradient(
+        begin: Alignment.bottomCenter,
+        end: Alignment.topCenter,
+        colors: [Color(0xFFA8EDEA), Color(0xFFFED6E3)],
+      ),
       child: GridView.builder(
         itemCount: items.length,
         shrinkWrap: true,
@@ -466,7 +471,7 @@ class _NavTile extends StatelessWidget {
       borderRadius: BorderRadius.circular(20),
       child: Container(
         decoration: BoxDecoration(
-          color: Colors.white.withValues(alpha: 0.78),
+          color: Colors.white,
           borderRadius: BorderRadius.circular(20),
           border: Border.all(color: Colors.white, width: 1.2),
         ),