diff --git a/backend/internal/api/auth.go b/backend/internal/api/auth.go
index 5aeea03..5eabc06 100644
--- a/backend/internal/api/auth.go
+++ b/backend/internal/api/auth.go
@@ -91,6 +91,7 @@ func Login(c *gin.Context) {
 	}
 
 	c.JSON(http.StatusOK, gin.H{
-		"token": token,
+		"token":    token,
+		"username": user.Username,
 	})
 }
diff --git a/frontend/lib/pages/login_page.dart b/frontend/lib/pages/login_page.dart
index c83f62c..600707b 100644
--- a/frontend/lib/pages/login_page.dart
+++ b/frontend/lib/pages/login_page.dart
@@ -32,7 +32,7 @@ class _LoginPageState extends State<LoginPage> {
       final response = await api.login(_usernameController.text, _passwordController.text);
       if (response.statusCode == 200) {
         final data = jsonDecode(response.body);
-        await auth.login(data['token']);
+        await auth.login(data['token'], data['username']);
       } else {
         final error = jsonDecode(response.body)['error'] ?? "Login Failed";
         ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(error)));
diff --git a/frontend/lib/pages/player_page.dart b/frontend/lib/pages/player_page.dart
index 7cffa5c..e8c3f5b 100644
--- a/frontend/lib/pages/player_page.dart
+++ b/frontend/lib/pages/player_page.dart
@@ -2,6 +2,7 @@ import 'dart:async';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 import 'package:video_player/video_player.dart';
+import '../providers/auth_provider.dart';
 import '../providers/settings_provider.dart';
 import '../services/chat_service.dart';
 
@@ -26,7 +27,7 @@ class _PlayerPageState extends State<PlayerPage> {
   final ChatService _chatService = ChatService();
   final TextEditingController _msgController = TextEditingController();
   final List<ChatMessage> _messages = [];
-  final List<Widget> _danmakus = []; // 为简单起见，这里存储弹幕 Widget
+  final List<Widget> _danmakus = [];
   
   bool _isError = false;
   String? _errorMessage;
@@ -51,7 +52,11 @@ class _PlayerPageState extends State<PlayerPage> {
 
   void _initializeChat() {
     final settings = context.read<SettingsProvider>();
-    _chatService.connect(settings.baseUrl, widget.roomId, "User_${widget.roomId}"); // 暂定用户名
+    final auth = context.read<AuthProvider>();
+    
+    // 使用真实用户名建立连接
+    final currentUsername = auth.username ?? "Guest_${widget.roomId}";
+    _chatService.connect(settings.baseUrl, widget.roomId, currentUsername);
 
     _chatService.messages.listen((msg) {
       if (mounted) {
@@ -67,7 +72,7 @@ class _PlayerPageState extends State<PlayerPage> {
 
   void _addDanmaku(String text) {
     final id = DateTime.now().millisecondsSinceEpoch;
-    final top = 20.0 + (id % 5) * 30.0; // 简单的多轨道显示
+    final top = 20.0 + (id % 6) * 30.0; 
     
     final danmaku = _DanmakuItem(
       key: ValueKey(id),
@@ -83,7 +88,8 @@ class _PlayerPageState extends State<PlayerPage> {
 
   void _sendMsg() {
     if (_msgController.text.isNotEmpty) {
-      _chatService.sendMessage(_msgController.text, "Me", widget.roomId);
+      final auth = context.read<AuthProvider>();
+      _chatService.sendMessage(_msgController.text, auth.username ?? "Anonymous", widget.roomId);
       _msgController.clear();
     }
   }
@@ -98,81 +104,139 @@ class _PlayerPageState extends State<PlayerPage> {
 
   @override
   Widget build(BuildContext context) {
+    bool isWide = MediaQuery.of(context).size.width > 900;
+
     return Scaffold(
       appBar: AppBar(title: Text(widget.title)),
-      body: Column(
-        children: [
-          // 视频播放器 + 弹幕层
-          Container(
+      body: isWide ? _buildWideLayout() : _buildMobileLayout(),
+    );
+  }
+
+  // 宽屏布局：左右分栏
+  Widget _buildWideLayout() {
+    return Row(
+      crossAxisAlignment: CrossAxisAlignment.stretch,
+      children: [
+        // 左侧视频区 (占比 75%)
+        Expanded(
+          flex: 3,
+          child: Container(
             color: Colors.black,
-            width: double.infinity,
-            height: 250,
-            child: Stack(
-              children: [
-                Center(
-                  child: _isError
-                      ? Text("Error: $_errorMessage", style: TextStyle(color: Colors.white))
-                      : _controller.value.isInitialized
-                          ? AspectRatio(aspectRatio: _controller.value.aspectRatio, child: VideoPlayer(_controller))
-                          : CircularProgressIndicator(),
-                ),
-                // 弹幕层
-                ..._danmakus,
-              ],
-            ),
+            child: _buildVideoWithDanmaku(),
           ),
-          // 评论区标题
-          Container(
-            padding: EdgeInsets.symmetric(horizontal: 16, vertical: 8),
-            color: Theme.of(context).colorScheme.surfaceVariant,
-            child: Row(
-              children: [
-                Icon(Icons.chat_bubble_outline, size: 16),
-                SizedBox(width: 8),
-                Text("Live Chat", style: TextStyle(fontWeight: FontWeight.bold)),
-              ],
-            ),
+        ),
+        // 右侧聊天区 (占比 25%)
+        Container(
+          width: 350,
+          decoration: BoxDecoration(
+            border: Border(left: BorderSide(color: Theme.of(context).dividerColor)),
           ),
-          // 消息列表
-          Expanded(
-            child: ListView.builder(
-              reverse: true,
-              itemCount: _messages.length,
-              itemBuilder: (context, index) {
-                final m = _messages[index];
-                return ListTile(
-                  dense: true,
-                  title: Text(
-                    "${m.username}: ${m.content}",
-                    style: TextStyle(color: m.type == "system" ? Colors.blue : null),
-                  ),
-                );
-              },
-            ),
+          child: _buildChatSection(),
+        ),
+      ],
+    );
+  }
+
+  // 移动端布局：上下堆叠
+  Widget _buildMobileLayout() {
+    return Column(
+      children: [
+        // 上方视频区
+        Container(
+          color: Colors.black,
+          width: double.infinity,
+          height: 250,
+          child: _buildVideoWithDanmaku(),
+        ),
+        // 下方聊天区
+        Expanded(child: _buildChatSection()),
+      ],
+    );
+  }
+
+  // 抽离视频播放器与弹幕组件
+  Widget _buildVideoWithDanmaku() {
+    return Stack(
+      children: [
+        Center(
+          child: _isError
+              ? Text("Error: $_errorMessage", style: TextStyle(color: Colors.white))
+              : _controller.value.isInitialized
+                  ? AspectRatio(
+                      aspectRatio: _controller.value.aspectRatio,
+                      child: VideoPlayer(_controller),
+                    )
+                  : CircularProgressIndicator(),
+        ),
+        // 弹幕层使用 ClipRect 裁剪，防止飘出视频区域
+        ClipRect(
+          child: Stack(children: _danmakus),
+        ),
+      ],
+    );
+  }
+
+  // 抽离聊天区域组件
+  Widget _buildChatSection() {
+    return Column(
+      children: [
+        Container(
+          padding: EdgeInsets.symmetric(horizontal: 16, vertical: 12),
+          color: Theme.of(context).colorScheme.surfaceVariant,
+          child: Row(
+            children: [
+              Icon(Icons.chat_bubble_outline, size: 16),
+              SizedBox(width: 8),
+              Text("Live Chat", style: TextStyle(fontWeight: FontWeight.bold)),
+            ],
           ),
-          // 输入框
-          Padding(
-            padding: const EdgeInsets.all(8.0),
-            child: Row(
-              children: [
-                Expanded(
-                  child: TextField(
-                    controller: _msgController,
-                    decoration: InputDecoration(
-                      hintText: "Say something...",
-                      border: OutlineInputBorder(borderRadius: BorderRadius.circular(20)),
-                      contentPadding: EdgeInsets.symmetric(horizontal: 16),
-                    ),
-                    onSubmitted: (_) => _sendMsg(),
+        ),
+        Expanded(
+          child: ListView.builder(
+            reverse: true,
+            padding: EdgeInsets.all(8),
+            itemCount: _messages.length,
+            itemBuilder: (context, index) {
+              final m = _messages[index];
+              return Padding(
+                padding: const EdgeInsets.symmetric(vertical: 4.0),
+                child: RichText(
+                  text: TextSpan(
+                    style: TextStyle(color: Theme.of(context).textTheme.bodyMedium?.color),
+                    children: [
+                      TextSpan(
+                        text: "${m.username}: ",
+                        style: TextStyle(fontWeight: FontWeight.bold, color: m.type == "system" ? Colors.blue : Theme.of(context).colorScheme.primary),
+                      ),
+                      TextSpan(text: m.content),
+                    ],
                   ),
                 ),
-                SizedBox(width: 8),
-                IconButton(icon: Icon(Icons.send, color: Colors.blue), onPressed: _sendMsg),
-              ],
-            ),
+              );
+            },
           ),
-        ],
-      ),
+        ),
+        Divider(height: 1),
+        Padding(
+          padding: const EdgeInsets.all(8.0),
+          child: Row(
+            children: [
+              Expanded(
+                child: TextField(
+                  controller: _msgController,
+                  decoration: InputDecoration(
+                    hintText: "Send a message...",
+                    border: OutlineInputBorder(borderRadius: BorderRadius.circular(20)),
+                    contentPadding: EdgeInsets.symmetric(horizontal: 16, vertical: 8),
+                  ),
+                  onSubmitted: (_) => _sendMsg(),
+                ),
+              ),
+              IconButton(icon: Icon(Icons.send, color: Theme.of(context).colorScheme.primary), onPressed: _sendMsg),
+            ],
+          ),
+        ),
+      ],
     );
   }
 }
@@ -190,13 +254,15 @@ class _DanmakuItem extends StatefulWidget {
 
 class __DanmakuItemState extends State<_DanmakuItem> with SingleTickerProviderStateMixin {
   late AnimationController _animationController;
-  late Animation<Offset> _animation;
+  late Animation<double> _animation;
 
   @override
   void initState() {
     super.initState();
-    _animationController = AnimationController(duration: const Duration(seconds: 8), vsync: this);
-    _animation = Tween<Offset>(begin: Offset(1.5, 0), end: Offset(-1.5, 0)).animate(_animationController);
+    _animationController = AnimationController(duration: const Duration(seconds: 10), vsync: this);
+    
+    // 使用相对位置：从右向左
+    _animation = Tween<double>(begin: 1.0, end: -0.5).animate(_animationController);
     
     _animationController.forward().then((_) => widget.onFinished());
   }
@@ -209,16 +275,24 @@ class __DanmakuItemState extends State<_DanmakuItem> with SingleTickerProviderSt
 
   @override
   Widget build(BuildContext context) {
-    return Positioned(
-      top: widget.top,
-      width: 300,
-      child: SlideTransition(
-        position: _animation,
-        child: Text(
-          widget.text,
-          style: TextStyle(color: Colors.white, fontWeight: FontWeight.bold, fontSize: 16, shadows: [Shadow(blurRadius: 2, color: Colors.black)]),
-        ),
-      ),
+    return AnimatedBuilder(
+      animation: _animation,
+      builder: (context, child) {
+        return Positioned(
+          top: widget.top,
+          // left 使用 MediaQuery 获取屏幕宽度进行动态计算
+          left: MediaQuery.of(context).size.width * _animation.value,
+          child: Text(
+            widget.text,
+            style: TextStyle(
+              color: Colors.white,
+              fontWeight: FontWeight.bold,
+              fontSize: 18,
+              shadows: [Shadow(blurRadius: 4, color: Colors.black, offset: Offset(1, 1))],
+            ),
+          ),
+        );
+      },
     );
   }
 }
diff --git a/frontend/lib/providers/auth_provider.dart b/frontend/lib/providers/auth_provider.dart
index 5bf4d57..5021d11 100644
--- a/frontend/lib/providers/auth_provider.dart
+++ b/frontend/lib/providers/auth_provider.dart
@@ -3,35 +3,42 @@ import 'package:shared_preferences/shared_preferences.dart';
 
 class AuthProvider with ChangeNotifier {
   String? _token;
+  String? _username; // 新增用户名状态
   bool _isAuthenticated = false;
 
   bool get isAuthenticated => _isAuthenticated;
   String? get token => _token;
+  String? get username => _username;
 
   AuthProvider() {
-    _loadToken();
+    _loadAuth();
   }
 
-  void _loadToken() async {
+  void _loadAuth() async {
     final prefs = await SharedPreferences.getInstance();
     _token = prefs.getString('token');
+    _username = prefs.getString('username');
     _isAuthenticated = _token != null;
     notifyListeners();
   }
 
-  Future<void> login(String token) async {
+  Future<void> login(String token, String username) async {
     _token = token;
+    _username = username;
     _isAuthenticated = true;
     final prefs = await SharedPreferences.getInstance();
     await prefs.setString('token', token);
+    await prefs.setString('username', username);
     notifyListeners();
   }
 
   Future<void> logout() async {
     _token = null;
+    _username = null;
     _isAuthenticated = false;
     final prefs = await SharedPreferences.getInstance();
     await prefs.remove('token');
+    await prefs.remove('username');
     notifyListeners();
   }
 }