✨ Better theme & background image

assets/locales/en_us.json

@@ -471,5 +471,11 @@
   "accountNav": "You",
   "performance": "Performance",
   "animatedMessageList": "Non-animated message list",
-  "animatedMessageListDesc": "Remove animation effects in message list, to reduce cause lag"
+  "animatedMessageListDesc": "Remove animation effects in message list, to reduce cause lag",
+  "theme": "Theme",
+  "globalTheme": "Global theme",
+  "agedTheme": "Old school style theme",
+  "agedThemeDesc": "Downgrade the global theme to Material Design 2. Unexpected issues may occur. For experimental use only.",
+  "appBackgroundImage": "Global background image",
+  "appBackgroundImageDesc": "The global background image will be displayed on all pages"
 }

assets/locales/zh_cn.json

@@ -467,5 +467,11 @@
   "accountNav": "您",
   "performance": "性能",
   "animatedMessageList": "无动画消息列表",
-  "animatedMessageListDesc": "在消息列表中禁用动画效果"
+  "animatedMessageListDesc": "在消息列表中禁用动画效果",
+  "theme": "主题",
+  "globalTheme": "全局应用主题",
+  "agedTheme": "过时主题",
+  "agedThemeDesc": "将全局主题降级为 Material Design 2，可能发生意料之外的问题，仅供实验使用",
+  "appBackgroundImage": "全局背景图片",
+  "appBackgroundImageDesc": "全局背景图片将会在所有页面中展示"
 }

lib/bootstrapper.dart

@@ -17,6 +17,7 @@ import 'package:solian/providers/relation.dart';
 import 'package:solian/providers/theme_switcher.dart';
 import 'package:solian/providers/websocket.dart';
 import 'package:solian/services.dart';
+import 'package:solian/widgets/root_container.dart';
 import 'package:solian/widgets/sized_container.dart';
 import 'package:flutter_app_update/flutter_app_update.dart';
 import 'package:version/version.dart';
@@ -255,8 +256,7 @@ class _BootstrapperShellState extends State<BootstrapperShell> {
   Widget build(BuildContext context) {
     if (_isBusy || _isErrored) {
       return GestureDetector(
-        child: Material(
+        child: RootContainer(
-          color: Theme.of(context).colorScheme.surface,
           child: Column(
             mainAxisSize: MainAxisSize.max,
             mainAxisAlignment: MainAxisAlignment.spaceAround,

lib/models/theme.dart

@@ -0,0 +1,50 @@
+import 'dart:ui';
+
+import 'package:json_annotation/json_annotation.dart';
+
+part 'theme.g.dart';
+
+@JsonSerializable(converters: [ColorConverter()])
+class SolianThemeData {
+  String id;
+  Color seedColor;
+  String? fontFamily;
+  List<String>? fontFamilyFallback;
+
+  SolianThemeData({
+    required this.id,
+    required this.seedColor,
+    this.fontFamily,
+    this.fontFamilyFallback,
+  });
+
+  factory SolianThemeData.fromJson(Map<String, dynamic> json) =>
+      _$SolianThemeDataFromJson(json);
+
+  Map<String, dynamic> toJson() => _$SolianThemeDataToJson(this);
+
+  @override
+  int get hashCode => id.hashCode;
+
+  @override
+  bool operator ==(Object other) {
+    if (other is SolianThemeData) {
+      return id == other.id;
+    }
+    return false;
+  }
+}
+
+class ColorConverter extends JsonConverter<Color, int> {
+  const ColorConverter();
+
+  @override
+  Color fromJson(int json) {
+    return Color(json);
+  }
+
+  @override
+  int toJson(Color object) {
+    return object.value;
+  }
+}

lib/models/theme.g.dart

@@ -0,0 +1,26 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'theme.dart';
+
+// **************************************************************************
+// JsonSerializableGenerator
+// **************************************************************************
+
+SolianThemeData _$SolianThemeDataFromJson(Map<String, dynamic> json) =>
+    SolianThemeData(
+      id: json['id'] as String,
+      seedColor:
+          const ColorConverter().fromJson((json['seed_color'] as num).toInt()),
+      fontFamily: json['font_family'] as String?,
+      fontFamilyFallback: (json['font_family_fallback'] as List<dynamic>?)
+          ?.map((e) => e as String)
+          .toList(),
+    );
+
+Map<String, dynamic> _$SolianThemeDataToJson(SolianThemeData instance) =>
+    <String, dynamic>{
+      'id': instance.id,
+      'seed_color': const ColorConverter().toJson(instance.seedColor),
+      'font_family': instance.fontFamily,
+      'font_family_fallback': instance.fontFamilyFallback,
+    };

lib/providers/theme_switcher.dart

@@ -1,5 +1,8 @@
+import 'dart:convert';
+
 import 'package:flutter/material.dart';
 import 'package:shared_preferences/shared_preferences.dart';
+import 'package:solian/models/theme.dart';
 import 'package:solian/theme.dart';
 
 class ThemeSwitcher extends ChangeNotifier {
@@ -13,11 +16,21 @@ class ThemeSwitcher extends ChangeNotifier {
 
   Future<void> restoreTheme() async {
     final prefs = await SharedPreferences.getInstance();
-    if (prefs.containsKey('global_theme_color')) {
+    if (prefs.containsKey('global_theme')) {
-      final value = prefs.getInt('global_theme_color')!;
+      final value = SolianThemeData.fromJson(
-      final color = Color(value);
+        jsonDecode(prefs.getString('global_theme')!),
-      lightThemeData = AppTheme.build(Brightness.light, seedColor: color);
+      );
-      darkThemeData = AppTheme.build(Brightness.dark, seedColor: color);
+      final agedTheme = prefs.getBool('aged_theme');
+      lightThemeData = AppTheme.buildFromData(
+        Brightness.light,
+        value,
+        useMaterial3: agedTheme == null ? true : !agedTheme,
+      );
+      darkThemeData = AppTheme.buildFromData(
+        Brightness.dark,
+        value,
+        useMaterial3: agedTheme == null ? true : !agedTheme,
+      );
       notifyListeners();
     }
   }
@@ -27,4 +40,25 @@ class ThemeSwitcher extends ChangeNotifier {
     darkThemeData = dark;
     notifyListeners();
   }
+
+  Future<void> setThemeData(SolianThemeData? data) async {
+    final prefs = await SharedPreferences.getInstance();
+    if (data == null) {
+      prefs.remove('global_theme');
+    } else {
+      prefs.setString(
+        'global_theme',
+        jsonEncode(data.toJson()),
+      );
+      lightThemeData = AppTheme.buildFromData(Brightness.light, data);
+      darkThemeData = AppTheme.buildFromData(Brightness.dark, data);
+      notifyListeners();
+    }
+  }
+
+  Future<void> setAgedTheme(bool enabled) async {
+    final prefs = await SharedPreferences.getInstance();
+    prefs.setBool('aged_theme', enabled);
+    await restoreTheme();
+  }
 }

lib/screens/about.dart

@@ -4,6 +4,7 @@ import 'package:get/get.dart';
 import 'package:intl/intl.dart';
 import 'package:package_info_plus/package_info_plus.dart';
 import 'package:shared_preferences/shared_preferences.dart';
+import 'package:solian/widgets/root_container.dart';
 import 'package:solian/widgets/sized_container.dart';
 import 'package:url_launcher/url_launcher_string.dart';
 
@@ -15,8 +16,7 @@ class AboutScreen extends StatelessWidget {
     const denseButtonStyle =
         ButtonStyle(visualDensity: VisualDensity(vertical: -4));
 
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: SizedBox(
         width: double.infinity,
         child: Column(

lib/screens/account.dart

@@ -7,6 +7,7 @@ import 'package:solian/providers/account_status.dart';
 import 'package:solian/providers/relation.dart';
 import 'package:solian/router.dart';
 import 'package:solian/widgets/account/account_heading.dart';
+import 'package:solian/widgets/root_container.dart';
 import 'package:solian/widgets/sized_container.dart';
 import 'package:badges/badges.dart' as badges;
 
@@ -49,8 +50,7 @@ class _AccountScreenState extends State<AccountScreen> {
 
     final AuthProvider auth = Get.find();
 
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: SafeArea(
         child: Obx(() {
           if (auth.isAuthorized.isFalse) {

lib/screens/account/friend.dart

@@ -6,6 +6,7 @@ import 'package:solian/models/relations.dart';
 import 'package:solian/providers/relation.dart';
 import 'package:solian/theme.dart';
 import 'package:solian/widgets/account/relative_list.dart';
+import 'package:solian/widgets/root_container.dart';
 
 class FriendScreen extends StatefulWidget {
   const FriendScreen({super.key});
@@ -117,8 +118,7 @@ class _FriendScreenState extends State<FriendScreen>
 
   @override
   Widget build(BuildContext context) {
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: Scaffold(
         appBar: AppBar(
           centerTitle: false,

lib/screens/account/preferences/notifications.dart

@@ -6,6 +6,7 @@ import 'package:google_fonts/google_fonts.dart';
 import 'package:solian/exceptions/request.dart';
 import 'package:solian/exts.dart';
 import 'package:solian/providers/auth.dart';
+import 'package:solian/widgets/root_container.dart';
 
 class NotificationPreferencesScreen extends StatefulWidget {
   const NotificationPreferencesScreen({super.key});
@@ -74,8 +75,7 @@ class _NotificationPreferencesScreenState
 
   @override
   Widget build(BuildContext context) {
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: Column(
         children: [
           if (_isBusy) const LinearProgressIndicator().animate().scaleX(),

lib/screens/account/profile_edit.dart

@@ -12,6 +12,7 @@ import 'package:solian/providers/auth.dart';
 import 'package:solian/providers/content/attachment.dart';
 import 'package:solian/services.dart';
 import 'package:solian/widgets/account/account_avatar.dart';
+import 'package:solian/widgets/root_container.dart';
 
 class PersonalizeScreen extends StatefulWidget {
   const PersonalizeScreen({super.key});
@@ -186,8 +187,7 @@ class _PersonalizeScreenState extends State<PersonalizeScreen> {
   Widget build(BuildContext context) {
     const double padding = 32;
 
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: ListView(
         children: [
           if (_isBusy) const LinearProgressIndicator().animate().scaleX(),

lib/screens/account/profile_page.dart

@@ -28,6 +28,7 @@ import 'package:solian/widgets/daily_sign/history_chart.dart';
 import 'package:solian/widgets/posts/post_list.dart';
 import 'package:solian/widgets/posts/post_warped_list.dart';
 import 'package:solian/widgets/reports/abuse_report.dart';
+import 'package:solian/widgets/root_container.dart';
 import 'package:solian/widgets/sized_container.dart';
 
 class AccountProfilePage extends StatefulWidget {
@@ -233,8 +234,7 @@ class _AccountProfilePageState extends State<AccountProfilePage> {
       return const Center(child: CircularProgressIndicator());
     }
 
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: DefaultTabController(
         length: 3,
         child: NestedScrollView(

lib/screens/auth/signin.dart

@@ -11,6 +11,7 @@ import 'package:solian/providers/content/realm.dart';
 import 'package:solian/providers/relation.dart';
 import 'package:solian/providers/websocket.dart';
 import 'package:solian/services.dart';
+import 'package:solian/widgets/root_container.dart';
 import 'package:solian/widgets/sized_container.dart';
 import 'package:url_launcher/url_launcher_string.dart';
 
@@ -216,8 +217,7 @@ class _SignInScreenState extends State<SignInScreen> {
 
   @override
   Widget build(BuildContext context) {
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: CenteredContainer(
         maxWidth: 360,
         child: PageTransitionSwitcher(

lib/screens/auth/signup.dart

@@ -3,6 +3,7 @@ import 'package:gap/gap.dart';
 import 'package:get/get.dart';
 import 'package:solian/exts.dart';
 import 'package:solian/services.dart';
+import 'package:solian/widgets/root_container.dart';
 import 'package:solian/widgets/sized_container.dart';
 import 'package:url_launcher/url_launcher_string.dart';
 
@@ -65,8 +66,7 @@ class _SignUpScreenState extends State<SignUpScreen> {
 
   @override
   Widget build(BuildContext context) {
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: CenteredContainer(
         maxWidth: 360,
         child: ListView(

lib/screens/channel/call/call.dart

@@ -11,6 +11,7 @@ import 'package:solian/widgets/app_bar_leading.dart';
 import 'package:solian/widgets/chat/call/call_controls.dart';
 import 'package:solian/widgets/chat/call/call_participant.dart';
 import 'package:livekit_client/livekit_client.dart' as livekit;
+import 'package:solian/widgets/root_container.dart';
 
 class CallScreen extends StatefulWidget {
   final bool hideAppBar;
@@ -197,8 +198,7 @@ class _CallScreenState extends State<CallScreen> with TickerProviderStateMixin {
   Widget build(BuildContext context) {
     final ChatCallProvider ctrl = Get.find();
 
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: Scaffold(
         appBar: widget.hideAppBar
             ? null

lib/screens/channel/channel_organize.dart

@@ -9,6 +9,7 @@ import 'package:solian/providers/content/channel.dart';
 import 'package:solian/router.dart';
 import 'package:solian/theme.dart';
 import 'package:solian/widgets/app_bar_title.dart';
+import 'package:solian/widgets/root_container.dart';
 import 'package:uuid/uuid.dart';
 
 class ChannelOrganizeArguments {
@@ -114,8 +115,7 @@ class _ChannelOrganizeScreenState extends State<ChannelOrganizeScreen> {
       ),
     ];
 
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: Scaffold(
         appBar: AppBar(
           title: AppBarTitle('channelOrganizing'.tr),

lib/screens/chat.dart

@@ -19,6 +19,7 @@ import 'package:solian/widgets/app_bar_title.dart';
 import 'package:solian/widgets/channel/channel_list.dart';
 import 'package:solian/widgets/chat/call/chat_call_indicator.dart';
 import 'package:solian/widgets/current_state_action.dart';
+import 'package:solian/widgets/root_container.dart';
 import 'package:solian/widgets/sidebar/empty_placeholder.dart';
 
 class ChatScreen extends StatelessWidget {
@@ -26,9 +27,8 @@ class ChatScreen extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    return Material(
+    return const RootContainer(
-      color: Theme.of(context).colorScheme.surface,
+      child: ChatList(),
-      child: const ChatList(),
     );
   }
 }
@@ -40,8 +40,7 @@ class ChatListShell extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: Row(
         children: [
           const SizedBox(
@@ -141,6 +140,7 @@ class _ChatListState extends State<ChatList> {
     return Obx(
       () => DefaultTabController(
         length: 2 + realms.availableRealms.length,
+        child: RootContainer(
           child: Scaffold(
             appBar: AppBar(
               leading: Obx(() {
@@ -166,7 +166,8 @@ class _ChatListState extends State<ChatList> {
                       child: ListTile(
                         title: Text('channelOrganizeCommon'.tr),
                         leading: const Icon(Icons.tag),
-                      contentPadding: const EdgeInsets.symmetric(horizontal: 8),
+                        contentPadding:
+                            const EdgeInsets.symmetric(horizontal: 8),
                       ),
                       onTap: () {
                         AppRouter.instance.pushNamed('channelOrganizing').then(
@@ -185,7 +186,8 @@ class _ChatListState extends State<ChatList> {
                           FontAwesomeIcons.userGroup,
                           size: 16,
                         ),
-                      contentPadding: const EdgeInsets.symmetric(horizontal: 8),
+                        contentPadding:
+                            const EdgeInsets.symmetric(horizontal: 8),
                       ),
                       onTap: () {
                         final ChannelProvider channels = Get.find();
@@ -217,7 +219,8 @@ class _ChatListState extends State<ChatList> {
                       children: [
                         CircleAvatar(
                           radius: 14,
-                        backgroundColor: Theme.of(context).colorScheme.primary,
+                          backgroundColor:
+                              Theme.of(context).colorScheme.primary,
                           child: const Icon(
                             Icons.forum,
                             size: 16,
@@ -318,6 +321,7 @@ class _ChatListState extends State<ChatList> {
             }),
           ),
         ),
+      ),
     );
   }
 }

lib/screens/explore.dart

@@ -15,6 +15,7 @@ import 'package:solian/widgets/app_bar_leading.dart';
 import 'package:solian/widgets/navigation/realm_switcher.dart';
 import 'package:solian/widgets/posts/post_shuffle_swiper.dart';
 import 'package:solian/widgets/posts/post_warped_list.dart';
+import 'package:solian/widgets/root_container.dart';
 
 class ExploreScreen extends StatefulWidget {
   const ExploreScreen({super.key});
@@ -56,8 +57,7 @@ class _ExploreScreenState extends State<ExploreScreen>
   Widget build(BuildContext context) {
     final AuthProvider auth = Get.find();
 
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: Scaffold(
         floatingActionButton: FloatingActionButton(
           child: const Icon(Icons.add),

lib/screens/feed/draft_box.dart

@@ -9,6 +9,7 @@ import 'package:solian/widgets/app_bar_leading.dart';
 import 'package:solian/widgets/app_bar_title.dart';
 import 'package:solian/widgets/posts/post_action.dart';
 import 'package:solian/widgets/posts/post_owned_list.dart';
+import 'package:solian/widgets/root_container.dart';
 
 class DraftBoxScreen extends StatefulWidget {
   const DraftBoxScreen({super.key});
@@ -54,8 +55,7 @@ class _DraftBoxScreenState extends State<DraftBoxScreen> {
 
   @override
   Widget build(BuildContext context) {
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: Scaffold(
         appBar: AppBar(
           leading: AppBarLeadingButton.adaptive(context),

lib/screens/posts/post_detail.dart

@@ -6,6 +6,7 @@ import 'package:solian/providers/content/posts.dart';
 import 'package:solian/providers/last_read.dart';
 import 'package:solian/widgets/posts/post_item.dart';
 import 'package:solian/widgets/posts/post_replies.dart';
+import 'package:solian/widgets/root_container.dart';
 
 class PostDetailScreen extends StatefulWidget {
   final String id;
@@ -47,8 +48,7 @@ class _PostDetailScreenState extends State<PostDetailScreen> {
 
   @override
   Widget build(BuildContext context) {
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: FutureBuilder(
         future: getDetail(),
         builder: (context, snapshot) {

lib/screens/posts/post_editor.dart

@@ -19,6 +19,7 @@ import 'package:solian/widgets/app_bar_title.dart';
 import 'package:solian/widgets/markdown_text_content.dart';
 import 'package:solian/widgets/posts/post_item.dart';
 import 'package:badges/badges.dart' as badges;
+import 'package:solian/widgets/root_container.dart';
 
 class PostPublishArguments {
   final Post? edit;
@@ -151,8 +152,7 @@ class _PostPublishScreenState extends State<PostPublishScreen> {
       )
     ];
 
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: Scaffold(
         appBar: AppBar(
           leading: AppBarLeadingButton.adaptive(context),

lib/screens/realms.dart

@@ -15,6 +15,7 @@ import 'package:solian/widgets/app_bar_leading.dart';
 import 'package:solian/widgets/app_bar_title.dart';
 import 'package:solian/widgets/auto_cache_image.dart';
 import 'package:solian/widgets/current_state_action.dart';
+import 'package:solian/widgets/root_container.dart';
 import 'package:solian/widgets/sized_container.dart';
 
 class RealmListScreen extends StatefulWidget {
@@ -58,8 +59,7 @@ class _RealmListScreenState extends State<RealmListScreen> {
   Widget build(BuildContext context) {
     final AuthProvider auth = Get.find();
 
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: Scaffold(
         appBar: AppBar(
           leading: AppBarLeadingButton.adaptive(context),

lib/screens/realms/realm_detail.dart

@@ -7,6 +7,7 @@ import 'package:solian/router.dart';
 import 'package:solian/screens/realms/realm_organize.dart';
 import 'package:solian/widgets/realms/realm_deletion.dart';
 import 'package:solian/widgets/realms/realm_member.dart';
+import 'package:solian/widgets/root_container.dart';
 
 class RealmDetailScreen extends StatefulWidget {
   final String alias;
@@ -86,7 +87,8 @@ class _RealmDetailScreenState extends State<RealmDetailScreen> {
       ),
     ];
 
-    return Column(
+    return RootContainer(
+      child: Column(
         children: [
           Padding(
             padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
@@ -141,6 +143,7 @@ class _RealmDetailScreenState extends State<RealmDetailScreen> {
             ),
           ),
         ],
+      ),
     );
   }
 }

lib/screens/realms/realm_organize.dart

@@ -13,6 +13,7 @@ import 'package:solian/router.dart';
 import 'package:solian/theme.dart';
 import 'package:solian/widgets/app_bar_leading.dart';
 import 'package:solian/widgets/app_bar_title.dart';
+import 'package:solian/widgets/root_container.dart';
 import 'package:uuid/uuid.dart';
 
 class RealmOrganizeArguments {
@@ -189,8 +190,7 @@ class _RealmOrganizeScreenState extends State<RealmOrganizeScreen> {
 
   @override
   Widget build(BuildContext context) {
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: Scaffold(
         appBar: AppBar(
           leading: AppBarLeadingButton.adaptive(context),

lib/screens/realms/realm_view.dart

@@ -16,6 +16,7 @@ import 'package:solian/theme.dart';
 import 'package:solian/widgets/app_bar_leading.dart';
 import 'package:solian/widgets/channel/channel_list.dart';
 import 'package:solian/widgets/posts/post_list.dart';
+import 'package:solian/widgets/root_container.dart';
 
 class RealmViewScreen extends StatefulWidget {
   final String alias;
@@ -86,8 +87,7 @@ class _RealmViewScreenState extends State<RealmViewScreen> {
 
   @override
   Widget build(BuildContext context) {
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: DefaultTabController(
         length: 2,
         child: NestedScrollView(

lib/screens/settings.dart

@@ -1,17 +1,25 @@
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:dropdown_button2/dropdown_button2.dart';
 import 'package:flutter/material.dart';
+import 'package:gap/gap.dart';
 import 'package:get/get.dart';
+import 'package:image_picker/image_picker.dart';
 import 'package:in_app_review/in_app_review.dart';
+import 'package:path_provider/path_provider.dart';
 import 'package:provider/provider.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import 'package:solian/exceptions/request.dart';
 import 'package:solian/exts.dart';
+import 'package:solian/models/theme.dart';
 import 'package:solian/platform.dart';
 import 'package:solian/providers/auth.dart';
 import 'package:solian/providers/database/database.dart';
 import 'package:solian/providers/theme_switcher.dart';
 import 'package:solian/router.dart';
-import 'package:solian/theme.dart';
 import 'package:solian/widgets/reports/abuse_report.dart';
+import 'package:solian/widgets/root_container.dart';
 
 class SettingScreen extends StatefulWidget {
   const SettingScreen({super.key});
@@ -22,6 +30,7 @@ class SettingScreen extends StatefulWidget {
 
 class _SettingScreenState extends State<SettingScreen> {
   SharedPreferences? _prefs;
+  String _docBasepath = '/';
 
   Widget _buildCaptionHeader(String title) {
     return Container(
@@ -32,39 +41,38 @@ class _SettingScreenState extends State<SettingScreen> {
     );
   }
 
-  Widget _buildThemeColorButton(String label, Color color) {
+  static final List<SolianThemeData> _presentTheme = [
-    return IconButton(
+    SolianThemeData(
-      icon: Icon(Icons.circle, color: color),
+      id: 'themeColorRed',
-      tooltip: label,
+      seedColor: const Color.fromRGBO(154, 98, 91, 1),
-      onPressed: () {
-        context.read<ThemeSwitcher>().setTheme(
-              AppTheme.build(
-                Brightness.light,
-                seedColor: color,
     ),
-              AppTheme.build(
+    SolianThemeData(
-                Brightness.dark,
+      id: 'themeColorBlue',
-                seedColor: color,
+      seedColor: const Color.fromRGBO(103, 96, 193, 1),
+    ),
+    SolianThemeData(
+      id: 'themeColorMiku',
+      seedColor: const Color.fromRGBO(56, 120, 126, 1),
+    ),
+    SolianThemeData(
+      id: 'themeColorKagamine',
+      seedColor: const Color.fromRGBO(244, 183, 63, 1),
+    ),
+    SolianThemeData(
+      id: 'themeColorLuka',
+      seedColor: const Color.fromRGBO(243, 174, 218, 1),
     ),
-            );
-        _prefs?.setInt('global_theme_color', color.value);
-        context.clearSnackbar();
-        context.showSnackbar('themeColorApplied'.tr);
-      },
-    );
-  }
-
-  static final List<(String, Color)> _presentTheme = [
-    ('themeColorRed', const Color.fromRGBO(154, 98, 91, 1)),
-    ('themeColorBlue', const Color.fromRGBO(103, 96, 193, 1)),
-    ('themeColorMiku', const Color.fromRGBO(56, 120, 126, 1)),
-    ('themeColorKagamine', const Color.fromRGBO(244, 183, 63, 1)),
-    ('themeColorLuka', const Color.fromRGBO(243, 174, 218, 1)),
   ];
 
   @override
   void initState() {
     super.initState();
+    getApplicationDocumentsDirectory().then((dir) {
+      _docBasepath = dir.path;
+      if (mounted) {
+        setState(() {});
+      }
+    });
     SharedPreferences.getInstance().then((inst) {
       _prefs = inst;
       if (mounted) {
@@ -75,19 +83,100 @@ class _SettingScreenState extends State<SettingScreen> {
 
   @override
   Widget build(BuildContext context) {
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: ListView(
         children: [
-          _buildCaptionHeader('themeColor'.tr),
+          _buildCaptionHeader('theme'.tr),
-          SizedBox(
+          ListTile(
-            height: 56,
+            leading: const Icon(Icons.palette),
-            child: ListView(
+            contentPadding: const EdgeInsets.symmetric(horizontal: 22),
-              scrollDirection: Axis.horizontal,
+            title: Text('globalTheme'.tr),
-              children: _presentTheme
+            trailing: DropdownButtonHideUnderline(
-                  .map((x) => _buildThemeColorButton(x.$1, x.$2))
+              child: DropdownButton2<SolianThemeData>(
+                isExpanded: true,
+                hint: Text(
+                  'theme'.tr,
+                  style: TextStyle(
+                    fontSize: 14,
+                    color: Theme.of(context).hintColor,
+                  ),
+                ),
+                items: _presentTheme
+                    .map((SolianThemeData item) =>
+                        DropdownMenuItem<SolianThemeData>(
+                          value: item,
+                          child: Row(
+                            crossAxisAlignment: CrossAxisAlignment.center,
+                            children: [
+                              Icon(Icons.circle, color: item.seedColor),
+                              const Gap(8),
+                              Text(
+                                item.id.tr,
+                                style: const TextStyle(
+                                  fontSize: 14,
+                                ),
+                              ),
+                            ],
+                          ),
+                        ))
                     .toList(),
-            ).paddingSymmetric(horizontal: 12, vertical: 8),
+                value: (_prefs?.containsKey('global_theme') ?? false)
+                    ? SolianThemeData.fromJson(
+                        jsonDecode(_prefs!.getString('global_theme')!),
+                      )
+                    : null,
+                onChanged: (SolianThemeData? value) {
+                  context.read<ThemeSwitcher>().setThemeData(value);
+                  setState(() {});
+                },
+                buttonStyleData: const ButtonStyleData(
+                  padding: EdgeInsets.symmetric(horizontal: 8),
+                  height: 40,
+                  width: 140,
+                ),
+                menuItemStyleData: const MenuItemStyleData(
+                  height: 40,
+                ),
+              ),
+            ),
+          ),
+          CheckboxListTile(
+            secondary: const Icon(Icons.military_tech),
+            contentPadding: const EdgeInsets.symmetric(horizontal: 22),
+            title: Text('agedTheme'.tr),
+            subtitle: Text('agedThemeDesc'.tr),
+            value: _prefs?.getBool('aged_theme') ?? false,
+            onChanged: (value) {
+              if (value != null) {
+                context.read<ThemeSwitcher>().setAgedTheme(value);
+              }
+              setState(() {});
+            },
+          ),
+          if (!PlatformInfo.isWeb)
+            ListTile(
+              leading: const Icon(Icons.wallpaper),
+              contentPadding: const EdgeInsets.only(left: 22, right: 31),
+              title: Text('appBackgroundImage'.tr),
+              subtitle: Text('appBackgroundImageDesc'.tr),
+              trailing: File('$_docBasepath/app_background_image').existsSync()
+                  ? const Icon(Icons.check_box)
+                  : const Icon(Icons.check_box_outline_blank),
+              onTap: () async {
+                if (File('$_docBasepath/app_background_image').existsSync()) {
+                  File('$_docBasepath/app_background_image').deleteSync();
+                } else {
+                  final image = await ImagePicker().pickImage(
+                    source: ImageSource.gallery,
+                  );
+                  if (image == null) return;
+
+                  await File(image.path)
+                      .copy('$_docBasepath/app_background_image');
+                }
+
+                setState(() {});
+              },
             ),
           _buildCaptionHeader('notification'.tr),
           Tooltip(

lib/shells/title_shell.dart

@@ -5,6 +5,7 @@ import 'package:solian/theme.dart';
 import 'package:solian/widgets/app_bar_title.dart';
 import 'package:solian/widgets/app_bar_leading.dart';
 import 'package:solian/widgets/current_state_action.dart';
+import 'package:solian/widgets/root_container.dart';
 
 class TitleShell extends StatelessWidget {
   final bool showAppBar;
@@ -26,7 +27,8 @@ class TitleShell extends StatelessWidget {
   Widget build(BuildContext context) {
     assert(state != null || title != null);
 
-    return Scaffold(
+    return RootContainer(
+      child: Scaffold(
         appBar: showAppBar
             ? AppBar(
                 leading: AppBarLeadingButton.adaptive(context),
@@ -44,6 +46,7 @@ class TitleShell extends StatelessWidget {
               )
             : null,
         body: child,
+      ),
     );
   }
 }

lib/theme.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:solian/models/theme.dart';
 import 'package:solian/platform.dart';
 
 abstract class AppTheme {
@@ -38,6 +39,7 @@ abstract class AppTheme {
         brightness: brightness,
         seedColor: seedColor ?? const Color.fromRGBO(154, 98, 91, 1),
       ),
+      scaffoldBackgroundColor: Colors.transparent,
       snackBarTheme: const SnackBarThemeData(
         behavior: SnackBarBehavior.floating,
       ),
@@ -55,4 +57,36 @@ abstract class AppTheme {
       ),
     );
   }
+
+  static ThemeData buildFromData(
+    Brightness brightness,
+    SolianThemeData data, {
+    bool useMaterial3 = true,
+  }) {
+    return ThemeData(
+      brightness: brightness,
+      useMaterial3: useMaterial3,
+      colorScheme: ColorScheme.fromSeed(
+        brightness: brightness,
+        seedColor: data.seedColor,
+      ),
+      snackBarTheme: const SnackBarThemeData(
+        behavior: SnackBarBehavior.floating,
+      ),
+      scaffoldBackgroundColor: Colors.transparent,
+      fontFamily: data.fontFamily ?? 'Comfortaa',
+      fontFamilyFallback: data.fontFamilyFallback ??
+          [
+            'NotoSansSC',
+            'NotoSansHK',
+            'NotoSansJP',
+            if (PlatformInfo.isWeb) 'NotoSansEmoji',
+          ],
+      typography: Typography.material2021(
+        colorScheme: brightness == Brightness.light
+            ? const ColorScheme.light()
+            : const ColorScheme.dark(),
+      ),
+    );
+  }
 }

lib/widgets/root_container.dart

@@ -0,0 +1,48 @@
+import 'dart:io';
+
+import 'package:flutter/material.dart';
+import 'package:path_provider/path_provider.dart';
+import 'package:solian/platform.dart';
+
+class RootContainer extends StatelessWidget {
+  final Widget? child;
+
+  const RootContainer({super.key, this.child});
+
+  @override
+  Widget build(BuildContext context) {
+    return FutureBuilder(
+      future: PlatformInfo.isWeb
+          ? Future.value(null)
+          : getApplicationDocumentsDirectory(),
+      builder: (context, snapshot) {
+        if (snapshot.hasData) {
+          final path = '${snapshot.data!.path}/app_background_image';
+          final file = File(path);
+          if (file.existsSync()) {
+            return Material(
+              color: Theme.of(context).colorScheme.surface,
+              child: Container(
+                decoration: BoxDecoration(
+                  backgroundBlendMode: BlendMode.darken,
+                  color: Theme.of(context).colorScheme.surface,
+                  image: DecorationImage(
+                    opacity: 0.5,
+                    image: FileImage(file),
+                    fit: BoxFit.cover,
+                  ),
+                ),
+                child: child,
+              ),
+            );
+          }
+        }
+
+        return Material(
+          color: Theme.of(context).colorScheme.surface,
+          child: child,
+        );
+      },
+    );
+  }
+}

lib/widgets/sidebar/empty_placeholder.dart

@@ -1,12 +1,12 @@
 import 'package:flutter/material.dart';
+import 'package:solian/widgets/root_container.dart';
 
 class EmptyPagePlaceholder extends StatelessWidget {
   const EmptyPagePlaceholder({super.key});
 
   @override
   Widget build(BuildContext context) {
-    return Material(
+    return RootContainer(
-      color: Theme.of(context).colorScheme.surface,
       child: Center(
         child: ClipRRect(
           borderRadius: const BorderRadius.all(Radius.circular(12)),