fix(flutter): 放大透明播放按钮

lib/pages/player/widgets/player_center_toggle.dart

@@ -4,6 +4,12 @@ import 'package:flutter/material.dart';
 
 import '../../../core/theme/app_colors.dart';
 
+const double _toggleSize = 72;
+const double _iconSize = 40;
+const List<Shadow> _iconShadows = [
+  Shadow(color: Colors.black54, blurRadius: 12),
+];
+
 /// 首页沉浸流与全屏播放器共用的播放/暂停按钮。
 class PlayerCenterToggle extends StatelessWidget {
   const PlayerCenterToggle({
@@ -23,12 +29,13 @@ class PlayerCenterToggle extends StatelessWidget {
       child: GestureDetector(
         onTap: onTap,
         child: SizedBox(
-          width: 52,
+          width: _toggleSize,
-          height: 52,
+          height: _toggleSize,
           child: Icon(
             playing ? Icons.pause_rounded : Icons.play_arrow_rounded,
             color: AppColors.onPrimary,
-            size: 26,
+            size: _iconSize,
+            shadows: _iconShadows,
           ),
         ),
       ),

test/player/player_center_toggle_test.dart

@@ -6,7 +6,9 @@ import 'package:fruitshorts/core/theme/app_colors.dart';
 import 'package:fruitshorts/pages/player/widgets/player_center_toggle.dart';
 
 void main() {
-  testWidgets('should_use_one_shared_52px_center_toggle_style', (tester) async {
+  testWidgets('should_use_one_shared_72px_transparent_toggle_style', (
+    tester,
+  ) async {
     await tester.pumpWidget(
       MaterialApp(
         home: Scaffold(
@@ -32,7 +34,7 @@ void main() {
       Key('test-center-toggle-a'),
       Key('player-play-toggle'),
     ]) {
-      expect(tester.getSize(find.byKey(key)), const Size(52, 52));
+      expect(tester.getSize(find.byKey(key)), const Size(72, 72));
       // 暂停按钮改为透明背景，容器已不再绘制任何底色或装饰。
       expect(
         find.descendant(of: find.byKey(key), matching: find.byType(Container)),
@@ -41,8 +43,10 @@ void main() {
       final icon = tester.widget<Icon>(
         find.descendant(of: find.byKey(key), matching: find.byType(Icon)),
       );
-      expect(icon.size, 26);
+      expect(icon.size, 40);
       expect(icon.color, AppColors.onPrimary);
+      expect(icon.shadows, isNotNull);
+      expect(icon.shadows, isNotEmpty);
     }
   });
 }