fix: use blue filled Dock icons on gray glass

mobile/lib/widgets/glass_dock.dart

@@ -21,7 +21,6 @@ class GlassDock extends StatefulWidget {
 class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
   static const _width = 264.0, _height = 68.0, _inset = 3.0, _travel = 86.0;
   static const _blue = Color(0xFF007AFF);
-  static const _selectedInk = Color(0xFF62666C);
   late final AnimationController _motion = AnimationController.unbounded(
     vsync: this,
     value: widget.selectedIndex.toDouble(),
@@ -181,7 +180,7 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
                 child: Row(
                   children: [
                     _item(0, Icons.calendar_month_rounded, '课表'),
-                    _item(1, Icons.assignment_outlined, '考试'),
+                    _item(1, Icons.assignment_rounded, '考试'),
                     _item(2, Icons.person_rounded, '个人设置'),
                   ],
                 ),
@@ -253,7 +252,7 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
               icon,
               size: 27,
               color: index == _position.round().clamp(0, 2)
-                  ? _selectedInk
+                  ? _blue
                   : _blue.withValues(alpha: 0.48),
             ),
           ),