fix(ui): 骨架屏扫光收窄压淡

lib/core/widgets/drama_grid_skeleton.dart

@@ -12,7 +12,7 @@ const double _shimmerTravel = 2.4;
 const double _shimmerStart = -1.2;
 const double _subtitleWidthFactor = 0.62;
 const double _shimmerPhaseStep = 0.13;
-const Color _shimmerHighlight = Color(0x12FFFFFF);
+const Color _shimmerHighlight = Color(0x0DFFFFFF);
 
 /// 首页短剧网格的占位。行数至少铺满可视高度，并带一道扫光。
 class DramaGridSkeleton extends StatefulWidget {
@@ -116,41 +116,48 @@ class _SkeletonCard extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final phase = (shimmerValue + index * _shimmerPhaseStep) % 1.0;
-    return ShaderMask(
-      blendMode: BlendMode.srcATop,
-      shaderCallback: (bounds) => _cardShader(bounds, phase),
-      child: Column(
-        key: Key('drama-grid-skeleton-$index'),
-        crossAxisAlignment: CrossAxisAlignment.start,
-        children: [
-          AspectRatio(
-            aspectRatio: AppDimens.cardCoverAspectRatio,
-            child: const _SkeletonBlock(),
+    return Stack(
+      key: Key('drama-grid-skeleton-$index'),
+      children: [
+        Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            AspectRatio(
+              aspectRatio: AppDimens.cardCoverAspectRatio,
+              child: const _SkeletonBlock(),
+            ),
+            const SizedBox(height: AppDimens.cardCoverTitleGap),
+            const _SkeletonBar(),
+            const SizedBox(height: AppDimens.skeletonTitleBarGap),
+            const FractionallySizedBox(
+              widthFactor: _subtitleWidthFactor,
+              child: _SkeletonBar(),
+            ),
+          ],
+        ),
+        Positioned.fill(
+          child: IgnorePointer(
+            child: ClipRRect(
+              borderRadius: BorderRadius.circular(AppDimens.homeCardRadius),
+              child: DecoratedBox(
+                decoration: BoxDecoration(gradient: _cardHighlight(phase)),
+              ),
+            ),
           ),
-          const SizedBox(height: AppDimens.cardCoverTitleGap),
-          const _SkeletonBar(),
-          const SizedBox(height: AppDimens.skeletonTitleBarGap),
-          const FractionallySizedBox(
-            widthFactor: _subtitleWidthFactor,
-            child: _SkeletonBar(),
-          ),
-        ],
-      ),
+        ),
+      ],
     );
   }
 }
 
-Shader _cardShader(Rect bounds, double shimmerValue) {
+LinearGradient _cardHighlight(double shimmerValue) {
   final shift = _shimmerStart + _shimmerTravel * shimmerValue;
   return LinearGradient(
     begin: Alignment(shift, -0.3),
     end: Alignment(shift + 1, 0.3),
-    colors: const [
-      AppColors.skeletonSurface,
-      _shimmerHighlight,
-      AppColors.skeletonSurface,
-    ],
-  ).createShader(bounds);
+    colors: const [Colors.transparent, _shimmerHighlight, Colors.transparent],
+    stops: const [0.42, 0.5, 0.58],
+  );
 }
 
 class _SkeletonBlock extends StatelessWidget {

test/discover/drama_grid_skeleton_test.dart

@@ -5,7 +5,7 @@ import 'package:flutter_test/flutter_test.dart';
 import 'package:fruitshorts/core/widgets/drama_grid_skeleton.dart';
 
 void main() {
-  testWidgets('renders one local shimmer mask per skeleton card', (
+  testWidgets('renders one narrow highlight overlay per skeleton card', (
     tester,
   ) async {
     tester.view.physicalSize = const Size(390, 1000);
@@ -28,20 +28,34 @@ void main() {
     await tester.pump(const Duration(milliseconds: 100));
 
     expect(find.byType(GridView), findsOneWidget);
-    expect(
-      find.ancestor(
-        of: find.byType(GridView),
-        matching: find.byType(ShaderMask),
-      ),
-      findsNothing,
-    );
+    expect(find.byType(ShaderMask), findsNothing);
     for (var index = 0; index < 9; index++) {
       final card = find.byKey(Key('drama-grid-skeleton-$index'));
       expect(card, findsOneWidget);
       expect(
-        find.ancestor(of: card, matching: find.byType(ShaderMask)),
+        find.descendant(of: card, matching: find.byType(IgnorePointer)),
         findsOneWidget,
       );
+      final overlay = find.descendant(
+        of: card,
+        matching: find.byWidgetPredicate(
+          (widget) =>
+              widget is DecoratedBox &&
+              widget.decoration is BoxDecoration &&
+              (widget.decoration as BoxDecoration).gradient != null,
+        ),
+      );
+      expect(overlay, findsOneWidget);
+      final decoration =
+          tester.widget<DecoratedBox>(overlay).decoration as BoxDecoration;
+      final gradient = decoration.gradient! as LinearGradient;
+      expect(gradient.colors, const [
+        Colors.transparent,
+        Color(0x0DFFFFFF),
+        Colors.transparent,
+      ]);
+      expect(gradient.stops, const [0.42, 0.5, 0.58]);
+      expect(gradient.stops![2] - gradient.stops![0], lessThanOrEqualTo(0.25));
     }
   });
 }