fix(ui): 打磨推荐追剧我的设置页间距与图标

lib/core/widgets/plain_page_scaffold.dart

@@ -3,7 +3,6 @@
 import 'package:flutter/material.dart';
 
 import '../theme/app_colors.dart';
-import '../theme/app_theme.dart';
 import 'subpage_header.dart';
 
 /// 二级页面通用骨架：返回栏 + 标题/副标题 + 可滚动内容，无底部导航。
@@ -29,7 +28,19 @@ class PlainPageScaffold extends StatelessWidget {
       key: pageKey,
       backgroundColor: AppColors.ink,
       body: DecoratedBox(
-        decoration: const BoxDecoration(gradient: AppTheme.pageGradient),
+        // 与首页各 tab 同族：纯黑底 + 顶部暗红光晕。
+        decoration: const BoxDecoration(
+          gradient: LinearGradient(
+            begin: Alignment.topCenter,
+            end: Alignment.bottomCenter,
+            colors: [
+              AppColors.followingGlow,
+              AppColors.followingGlowMid,
+              AppColors.appBackground,
+            ],
+            stops: [0, 0.14, 0.3],
+          ),
+        ),
         child: SafeArea(
           child: Column(
             crossAxisAlignment: CrossAxisAlignment.start,

lib/core/widgets/remote_image.dart

@@ -74,9 +74,13 @@ class RemoteImage extends StatelessWidget {
                       : null);
         final cacheWidth =
             decodeWidth ?? resolveImageDecodePixels(layoutWidth, pixelRatio);
-        final cacheHeight =
-            decodeHeight ??
-            (inferredHeight == null
+        // cover/contain 本身会保持宽高比，此时若同时强制 cacheWidth 和
+        // cacheHeight，解码会把竖版图强行拉成横版像素。只在显式指定了
+        // decodeHeight、或 fit 不保持宽高比时才限定解码高度。
+        final keepsAspectRatio =
+            fit == BoxFit.cover || fit == BoxFit.contain;
+        final cacheHeight = decodeHeight ??
+            (keepsAspectRatio || inferredHeight == null
                 ? null
                 : resolveImageDecodePixels(inferredHeight, pixelRatio));
         return Image.network(

lib/core/widgets/subpage_header.dart

@@ -8,7 +8,7 @@ const double _height = 52;
 const double _heightWithSubtitle = 64;
 const double _horizontal = 14;
 const double _backSize = 40;
-const double _backGap = 12;
+const double _backGap = 6;
 const double _titleFontSize = 18;
 const double _subtitleFontSize = 12;
 const double _actionGap = 8;
@@ -163,7 +163,7 @@ class AppSubpageHeader extends StatelessWidget {
                     style: TextStyle(
                       color: foreground,
                       fontSize: _titleFontSize,
-                      fontWeight: FontWeight.w800,
+                      fontWeight: FontWeight.w400,
                     ),
                   ),
                   if (subtitle != null) ...[