style: 统一全站深色视觉

lib/core/theme/app_theme.dart

@@ -8,12 +8,16 @@ import 'app_dimens.dart';
 
 /// 深色视觉主题（默认且唯一）。
 abstract final class AppTheme {
-  /// 页面背景：深色扁平，靠容器层次区分。
+  /// 页面背景：顶部暖黑、底部纯黑，避免旧深蓝渐变。
   static const LinearGradient pageGradient = LinearGradient(
     begin: Alignment.topCenter,
     end: Alignment.bottomCenter,
-    colors: [AppColors.surfaceTop, AppColors.ink],
-    stops: [0, 0.24],
+    colors: [
+      AppColors.mineGradientTop,
+      AppColors.mineGradientMiddle,
+      AppColors.mineGradientBottom,
+    ],
+    stops: [0, 0.4, 0.75],
   );
 
   /// 卡片阴影关闭，改用底色与分割线。
@@ -76,7 +80,7 @@ abstract final class AppTheme {
       ),
       textButtonTheme: TextButtonThemeData(
         style: TextButton.styleFrom(
-          foregroundColor: AppColors.secondary,
+          foregroundColor: AppColors.primary,
           shape: RoundedRectangleBorder(borderRadius: _buttonRadius),
         ),
       ),
@@ -107,12 +111,12 @@ abstract final class AppTheme {
       ),
       outlinedButtonTheme: OutlinedButtonThemeData(
         style: ButtonStyle(
-          foregroundColor: const WidgetStatePropertyAll(AppColors.blue),
+          foregroundColor: const WidgetStatePropertyAll(AppColors.textPrimary),
           minimumSize: const WidgetStatePropertyAll(
             Size(0, AppDimens.buttonHeight),
           ),
           side: const WidgetStatePropertyAll(
-            BorderSide(color: AppColors.border),
+            BorderSide(color: AppColors.mineOutline),
           ),
           shape: WidgetStatePropertyAll(
             RoundedRectangleBorder(borderRadius: _buttonRadius),
@@ -148,20 +152,20 @@ abstract final class AppTheme {
         ),
       ),
       appBarTheme: const AppBarTheme(
-        backgroundColor: AppColors.card,
-        foregroundColor: AppColors.onSurface,
+        backgroundColor: AppColors.transparent,
+        foregroundColor: AppColors.textPrimary,
         elevation: 0,
         scrolledUnderElevation: 0,
         surfaceTintColor: AppColors.transparent,
         systemOverlayStyle: SystemUiOverlayStyle.light,
         titleTextStyle: TextStyle(
-          color: AppColors.onSurface,
+          color: AppColors.textPrimary,
           fontFamily: 'Outfit',
           fontSize: AppDimens.pageTitle,
           fontWeight: FontWeight.w800,
         ),
       ),
-      iconTheme: const IconThemeData(color: AppColors.onSurface),
+      iconTheme: const IconThemeData(color: AppColors.textPrimary),
       dividerTheme: const DividerThemeData(
         color: AppColors.border,
         thickness: 1,