style(theme): 客户端切换深色视觉风格

lib/core/widgets/app_bottom_nav.dart

@@ -26,7 +26,7 @@ class AppBottomNavItem {
   final bool selected;
 }
 
-/// 四槽底部导航：首页 feed 用深色样式，其它页面保持浅色暖橙风格。
+/// 四槽底部导航：所有页面统一深色底与浅色图标。
 class AppBottomNav extends StatelessWidget {
   const AppBottomNav({
     super.key,
@@ -47,24 +47,22 @@ class AppBottomNav extends StatelessWidget {
       key: barKey,
       height: AppDimens.navHeight,
       decoration: BoxDecoration(
-        color: dark ? Colors.black : backgroundColor.withValues(alpha: 0.95),
-        border: Border(
-          top: BorderSide(color: dark ? Colors.white12 : AppColors.border),
-        ),
+        color: dark ? AppColors.bar : backgroundColor.withValues(alpha: 0.96),
+        border: const Border(top: BorderSide(color: AppColors.border)),
       ),
       child: Row(
         children: [
           for (final item in items)
             _NavDestination(
               item: item,
-              unselectedColor: dark ? Colors.white70 : AppColors.navUnselected,
+              unselectedColor: AppColors.navUnselected,
             ),
         ],
       ),
     );
     if (dark) {
       return ColoredBox(
-        color: Colors.black,
+        color: AppColors.bar,
         child: SafeArea(top: false, child: bar),
       );
     }

lib/core/widgets/auth_gate.dart

@@ -37,7 +37,7 @@ Future<bool> ensureSignedIn(BuildContext context) async {
             Text(
               l10n.authGateTitle,
               style: const TextStyle(
-                color: Colors.white,
+                color: AppColors.onSurface,
                 fontSize: 16,
                 fontWeight: FontWeight.w800,
               ),
@@ -98,7 +98,7 @@ class AuthGatePanel extends StatelessWidget {
               l10n.authGateTitle,
               textAlign: TextAlign.center,
               style: const TextStyle(
-                color: Colors.white,
+                color: AppColors.onSurface,
                 fontSize: 18,
                 fontWeight: FontWeight.w800,
               ),

lib/core/widgets/catalog_endpoint_editor.dart

@@ -5,6 +5,7 @@ import 'package:flutter/material.dart';
 
 import '../config/app_config.dart';
 import '../config/server_endpoint.dart';
+import '../theme/app_colors.dart';
 
 const String _title = '设置服务地址';
 const String _save = '保存';
@@ -94,7 +95,7 @@ class _CatalogEndpointDialogState extends State<_CatalogEndpointDialog> {
             const Text(
               _localNetworkHint,
               key: Key('catalog-debug-endpoint-hint'),
-              style: TextStyle(fontSize: 12, color: Colors.grey),
+              style: TextStyle(fontSize: 12, color: AppColors.muted),
             ),
             if (_error != null) ...[
               const SizedBox(height: 8),

lib/core/widgets/centered_toast.dart

@@ -4,6 +4,8 @@ import 'dart:async';
 
 import 'package:flutter/material.dart';
 
+import '../theme/app_colors.dart';
+
 const Key _toastKey = Key('centered-toast');
 const Duration _fadeDuration = Duration(milliseconds: 200);
 const Duration _visibleDuration = Duration(seconds: 2);
@@ -11,9 +13,8 @@ const double _toastRadius = 12;
 const double _toastMaxWidth = 320;
 const double _toastHorizontalInset = 20;
 const double _toastVerticalInset = 12;
-const double _toastBackgroundOpacity = 0.78;
 const TextStyle _toastTextStyle = TextStyle(
-  color: Colors.white,
+  color: AppColors.onSurface,
   fontSize: 14,
   height: 1.4,
   fontWeight: FontWeight.w500,
@@ -108,10 +109,9 @@ class _CenteredToastState extends State<_CenteredToast>
                 constraints: const BoxConstraints(maxWidth: _toastMaxWidth),
                 padding: _toastPadding,
                 decoration: BoxDecoration(
-                  color: Colors.black.withValues(
-                    alpha: _toastBackgroundOpacity,
-                  ),
+                  color: AppColors.raised,
                   borderRadius: BorderRadius.circular(_toastRadius),
+                  border: Border.all(color: AppColors.border),
                 ),
                 child: Text(
                   widget.message,

lib/core/widgets/empty_state.dart

@@ -87,12 +87,11 @@ class _EmptyMark extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    final dark = Theme.of(context).brightness == Brightness.dark;
     return Icon(
       icon,
       key: const Key('empty-state-icon'),
       size: compact ? _compactIconSize : _regularIconSize,
-      color: dark ? AppColors.gold : AppColors.blue,
+      color: AppColors.blueSoft,
     );
   }
 }

lib/core/widgets/glass_panel.dart

@@ -7,7 +7,7 @@ import 'package:flutter/material.dart';
 import '../theme/app_colors.dart';
 import '../theme/app_dimens.dart';
 
-/// 首页信息卡与浮层控件使用的浅色玻璃面板。
+/// 首页信息卡与浮层控件使用的深色玻璃面板。
 class GlassPanel extends StatelessWidget {
   const GlassPanel({
     super.key,
@@ -38,7 +38,7 @@ class GlassPanel extends StatelessWidget {
             const LinearGradient(
               begin: Alignment.topLeft,
               end: Alignment.bottomRight,
-              colors: [Color(0xE6FFFFFF), Color(0xB3FFFDFB)],
+              colors: [AppColors.glassSurfaceStart, AppColors.glassSurfaceEnd],
             ),
       ),
       child: Padding(padding: padding ?? EdgeInsets.zero, child: child),

lib/core/widgets/remote_image.dart

@@ -16,7 +16,7 @@ class RemoteImage extends StatelessWidget {
     this.showFallbackIcon = false,
     this.fallbackIconKey,
     this.fallbackAspectRatio,
-    this.fallbackColor = AppColors.bar,
+    this.fallbackColor = AppColors.raised,
   });
 
   final String path;

lib/core/widgets/subpage_header.dart

@@ -16,9 +16,6 @@ const double _iconSize = 22;
 const double _iconWeight = 600;
 const double _borderWidth = 1;
 const double _shadowBlur = 8;
-const Color _lightShadowColor = Color(0x14000000);
-const Color _darkBackground = Color(0x59000000);
-const Color _darkShadowColor = Color(0x33000000);
 const Offset _lightShadowOffset = Offset(0, 2);
 
 /// 二级页面统一圆形操作按钮，返回、分享和更多共用同一尺寸与表面样式。
@@ -52,14 +49,14 @@ class AppSubpageCircleButton extends StatelessWidget {
             shape: BoxShape.circle,
             boxShadow: [
               BoxShadow(
-                color: dark ? _darkShadowColor : _lightShadowColor,
+                color: dark ? AppColors.shadowSoft : AppColors.shadowSubtle,
                 blurRadius: _shadowBlur,
                 offset: dark ? Offset.zero : _lightShadowOffset,
               ),
             ],
           ),
           child: Material(
-            color: dark ? _darkBackground : AppColors.card,
+            color: dark ? AppColors.headerScrim : AppColors.card,
             shape: CircleBorder(
               side: dark
                   ? BorderSide.none
@@ -75,7 +72,7 @@ class AppSubpageCircleButton extends StatelessWidget {
               child: Center(
                 child: Icon(
                   icon,
-                  color: dark ? Colors.white : AppColors.onSurface,
+                  color: AppColors.onSurface,
                   size: _iconSize,
                   weight: _iconWeight,
                 ),
@@ -134,8 +131,8 @@ class AppSubpageHeader extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    final foreground = dark ? Colors.white : AppColors.onSurface;
-    final secondary = dark ? Colors.white70 : AppColors.muted;
+    final foreground = AppColors.onSurface;
+    final secondary = AppColors.muted;
     return SizedBox(
       key: const Key('subpage-header'),
       height: subtitle == null ? _height : _heightWithSubtitle,