diff --git a/frontend/mobile-app/lib/features/auth/presentation/pages/backup_mnemonic_page.dart b/frontend/mobile-app/lib/features/auth/presentation/pages/backup_mnemonic_page.dart
index 672f4a48..11567055 100644
--- a/frontend/mobile-app/lib/features/auth/presentation/pages/backup_mnemonic_page.dart
+++ b/frontend/mobile-app/lib/features/auth/presentation/pages/backup_mnemonic_page.dart
@@ -50,6 +50,10 @@ class _BackupMnemonicPageState extends ConsumerState<BackupMnemonicPage> {
 
   // 轮询定时器
   Timer? _pollTimer;
+  // 倒计时定时器
+  Timer? _countdownTimer;
+  // 倒计时剩余秒数 (100秒)
+  int _countdownSeconds = 100;
 
   @override
   void initState() {
@@ -60,8 +64,9 @@ class _BackupMnemonicPageState extends ConsumerState<BackupMnemonicPage> {
 
   @override
   void dispose() {
-    debugPrint('[BackupMnemonicPage] dispose - 取消轮询定时器');
+    debugPrint('[BackupMnemonicPage] dispose - 取消轮询定时器和倒计时');
     _pollTimer?.cancel();
+    _countdownTimer?.cancel();
     super.dispose();
   }
 
@@ -106,6 +111,7 @@ class _BackupMnemonicPageState extends ConsumerState<BackupMnemonicPage> {
           _errorMessage = null;
         });
         _startPolling();
+        _startCountdown();
       } else if (response.isFailed) {
         // 钱包生成失败
         debugPrint('[BackupMnemonicPage] _loadWalletInfo - 钱包生成失败');
@@ -132,6 +138,34 @@ class _BackupMnemonicPageState extends ConsumerState<BackupMnemonicPage> {
     return '${address.substring(0, 6)}...${address.substring(address.length - 4)}';
   }
 
+  /// 开始倒计时
+  void _startCountdown() {
+    _countdownTimer?.cancel();
+    _countdownSeconds = 100;
+    debugPrint('[BackupMnemonicPage] _startCountdown - 启动100秒倒计时');
+    _countdownTimer = Timer.periodic(const Duration(seconds: 1), (timer) {
+      if (!mounted) {
+        timer.cancel();
+        return;
+      }
+      if (_countdownSeconds > 0) {
+        setState(() {
+          _countdownSeconds--;
+        });
+      } else {
+        timer.cancel();
+        debugPrint('[BackupMnemonicPage] _startCountdown - 倒计时结束');
+      }
+    });
+  }
+
+  /// 停止倒计时
+  void _stopCountdown() {
+    _countdownTimer?.cancel();
+    _countdownTimer = null;
+    debugPrint('[BackupMnemonicPage] _stopCountdown - 停止倒计时');
+  }
+
   /// 开始轮询
   int _pollCount = 0;
   void _startPolling() {
@@ -162,6 +196,7 @@ class _BackupMnemonicPageState extends ConsumerState<BackupMnemonicPage> {
         if (response.isReady) {
           debugPrint('[BackupMnemonicPage] _startPolling - 钱包就绪! 停止轮询 (共轮询 $_pollCount 次)');
           timer.cancel();
+          _stopCountdown();
           final wordCount = response.mnemonic?.split(' ').length ?? 0;
           debugPrint('[BackupMnemonicPage] _startPolling - 助记词数量: $wordCount');
           setState(() {
@@ -176,6 +211,7 @@ class _BackupMnemonicPageState extends ConsumerState<BackupMnemonicPage> {
         } else if (response.isFailed) {
           debugPrint('[BackupMnemonicPage] _startPolling - 钱包生成失败，停止轮询');
           timer.cancel();
+          _stopCountdown();
           setState(() {
             _isLoading = false;
             _errorMessage = '钱包生成失败，请稍后重试';
@@ -367,15 +403,19 @@ ${DateTime.now().toString()}
             children: [
               // 顶部导航栏
               _buildAppBar(),
-              // 内容区域
+              // 内容区域 - 始终显示内容，加载时覆盖蒙版
               Expanded(
-                child: _isLoading
-                    ? _buildLoadingState()
-                    : _errorMessage != null
-                        ? _buildErrorState()
-                        : _buildContent(),
+                child: Stack(
+                  children: [
+                    // 底层：内容（始终显示，加载时显示占位数据）
+                    _buildContentWithPlaceholder(),
+                    // 顶层：加载蒙版或错误蒙版
+                    if (_isLoading) _buildLoadingOverlay(),
+                    if (_errorMessage != null) _buildErrorOverlay(),
+                  ],
+                ),
               ),
-              // 底部按钮区域 (非加载状态时显示)
+              // 底部按钮区域 (非加载状态且无错误时显示)
               if (!_isLoading && _errorMessage == null) _buildBottomButtons(),
             ],
           ),
@@ -384,37 +424,133 @@ ${DateTime.now().toString()}
     );
   }
 
-  /// 构建加载状态
-  Widget _buildLoadingState() {
-    return Center(
-      child: Column(
-        mainAxisAlignment: MainAxisAlignment.center,
+  /// 构建加载蒙版 - 覆盖助记词和地址区域，显示倒计时
+  Widget _buildLoadingOverlay() {
+    return Positioned.fill(
+      child: Container(
+        color: const Color(0xCC5D4037), // 半透明深棕色蒙版
+        child: Center(
+          child: Container(
+            margin: const EdgeInsets.symmetric(horizontal: 32),
+            padding: const EdgeInsets.all(32),
+            decoration: BoxDecoration(
+              color: const Color(0xFFFFFDF5),
+              borderRadius: BorderRadius.circular(20),
+              boxShadow: const [
+                BoxShadow(
+                  color: Color(0x33000000),
+                  blurRadius: 20,
+                  offset: Offset(0, 8),
+                ),
+              ],
+            ),
+            child: Column(
+              mainAxisSize: MainAxisSize.min,
+              children: [
+                // 安全图标
+                Container(
+                  width: 80,
+                  height: 80,
+                  decoration: BoxDecoration(
+                    color: const Color(0xFFFFF3D6),
+                    shape: BoxShape.circle,
+                    border: Border.all(
+                      color: const Color(0xFFD4A84B),
+                      width: 3,
+                    ),
+                  ),
+                  child: const Center(
+                    child: Icon(
+                      Icons.security,
+                      size: 40,
+                      color: Color(0xFFD4A84B),
+                    ),
+                  ),
+                ),
+                const SizedBox(height: 24),
+                // 提示文字
+                const Text(
+                  '正在进行钱包的安全计算',
+                  style: TextStyle(
+                    fontSize: 18,
+                    fontFamily: 'Inter',
+                    fontWeight: FontWeight.w700,
+                    color: Color(0xFF5D4037),
+                  ),
+                  textAlign: TextAlign.center,
+                ),
+                const SizedBox(height: 8),
+                const Text(
+                  '使用多方安全计算技术生成您的钱包',
+                  style: TextStyle(
+                    fontSize: 14,
+                    fontFamily: 'Inter',
+                    fontWeight: FontWeight.w500,
+                    color: Color(0xFF8B7355),
+                  ),
+                  textAlign: TextAlign.center,
+                ),
+                const SizedBox(height: 32),
+                // 倒计时圆环
+                _buildCountdownCircle(),
+                const SizedBox(height: 16),
+                // 倒计时文字
+                Text(
+                  '预计剩余 $_countdownSeconds 秒',
+                  style: const TextStyle(
+                    fontSize: 14,
+                    fontFamily: 'Inter',
+                    fontWeight: FontWeight.w500,
+                    color: Color(0xFF8B7355),
+                  ),
+                ),
+              ],
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+
+  /// 构建倒计时圆环
+  Widget _buildCountdownCircle() {
+    final progress = _countdownSeconds / 100.0;
+    return SizedBox(
+      width: 100,
+      height: 100,
+      child: Stack(
+        alignment: Alignment.center,
         children: [
-          const SizedBox(
-            width: 48,
-            height: 48,
+          // 背景圆环
+          SizedBox(
+            width: 100,
+            height: 100,
             child: CircularProgressIndicator(
-              strokeWidth: 3,
-              valueColor: AlwaysStoppedAnimation<Color>(Color(0xFFD4AF37)),
+              value: 1.0,
+              strokeWidth: 8,
+              backgroundColor: const Color(0xFFE8E0D0),
+              valueColor: const AlwaysStoppedAnimation<Color>(Color(0xFFE8E0D0)),
             ),
           ),
-          const SizedBox(height: 24),
-          const Text(
-            '正在生成您的钱包...',
-            style: TextStyle(
-              fontSize: 18,
-              fontFamily: 'Inter',
-              fontWeight: FontWeight.w600,
-              color: Color(0xFF5D4037),
+          // 进度圆环
+          SizedBox(
+            width: 100,
+            height: 100,
+            child: CircularProgressIndicator(
+              value: progress,
+              strokeWidth: 8,
+              backgroundColor: Colors.transparent,
+              valueColor: const AlwaysStoppedAnimation<Color>(Color(0xFFD4A84B)),
             ),
           ),
-          const SizedBox(height: 8),
-          const Text(
-            '请稍候，这可能需要几秒钟',
-            style: TextStyle(
-              fontSize: 14,
+          // 倒计时数字
+          Text(
+            '$_countdownSeconds',
+            style: const TextStyle(
+              fontSize: 32,
               fontFamily: 'Inter',
-              color: Color(0xFF8B7355),
+              fontWeight: FontWeight.w700,
+              color: Color(0xFFD4A84B),
             ),
           ),
         ],
@@ -422,75 +558,135 @@ ${DateTime.now().toString()}
     );
   }
 
-  /// 构建错误状态
-  Widget _buildErrorState() {
-    return Center(
-      child: Padding(
-        padding: const EdgeInsets.all(24),
-        child: Column(
-          mainAxisAlignment: MainAxisAlignment.center,
-          children: [
-            const Icon(
-              Icons.error_outline,
-              size: 64,
-              color: Color(0xFFCC6B2C),
-            ),
-            const SizedBox(height: 16),
-            Text(
-              _errorMessage!,
-              style: const TextStyle(
-                fontSize: 16,
-                fontFamily: 'Inter',
-                color: Color(0xFF5D4037),
-              ),
-              textAlign: TextAlign.center,
-            ),
-            const SizedBox(height: 24),
-            GestureDetector(
-              onTap: () {
-                setState(() {
-                  _isLoading = true;
-                  _errorMessage = null;
-                });
-                _loadWalletInfo();
-              },
-              child: Container(
-                padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 12),
-                decoration: BoxDecoration(
-                  color: const Color(0xFFD4AF37),
-                  borderRadius: BorderRadius.circular(8),
+  /// 构建错误蒙版
+  Widget _buildErrorOverlay() {
+    return Positioned.fill(
+      child: Container(
+        color: const Color(0xCC5D4037), // 半透明深棕色蒙版
+        child: Center(
+          child: Container(
+            margin: const EdgeInsets.symmetric(horizontal: 32),
+            padding: const EdgeInsets.all(32),
+            decoration: BoxDecoration(
+              color: const Color(0xFFFFFDF5),
+              borderRadius: BorderRadius.circular(20),
+              boxShadow: const [
+                BoxShadow(
+                  color: Color(0x33000000),
+                  blurRadius: 20,
+                  offset: Offset(0, 8),
                 ),
-                child: const Text(
-                  '重试',
-                  style: TextStyle(
-                    fontSize: 16,
-                    fontWeight: FontWeight.w600,
-                    color: Colors.white,
+              ],
+            ),
+            child: Column(
+              mainAxisSize: MainAxisSize.min,
+              children: [
+                // 错误图标
+                Container(
+                  width: 80,
+                  height: 80,
+                  decoration: const BoxDecoration(
+                    color: Color(0xFFFFE4E4),
+                    shape: BoxShape.circle,
+                  ),
+                  child: const Center(
+                    child: Icon(
+                      Icons.error_outline,
+                      size: 48,
+                      color: Color(0xFFCC6B2C),
+                    ),
                   ),
                 ),
-              ),
+                const SizedBox(height: 24),
+                // 错误标题
+                const Text(
+                  '钱包生成失败',
+                  style: TextStyle(
+                    fontSize: 18,
+                    fontFamily: 'Inter',
+                    fontWeight: FontWeight.w700,
+                    color: Color(0xFF5D4037),
+                  ),
+                  textAlign: TextAlign.center,
+                ),
+                const SizedBox(height: 8),
+                // 错误信息
+                Text(
+                  _errorMessage ?? '未知错误',
+                  style: const TextStyle(
+                    fontSize: 14,
+                    fontFamily: 'Inter',
+                    fontWeight: FontWeight.w500,
+                    color: Color(0xFF8B7355),
+                  ),
+                  textAlign: TextAlign.center,
+                ),
+                const SizedBox(height: 24),
+                // 重试按钮
+                GestureDetector(
+                  onTap: () {
+                    setState(() {
+                      _isLoading = true;
+                      _errorMessage = null;
+                      _countdownSeconds = 100;
+                    });
+                    _loadWalletInfo();
+                  },
+                  child: Container(
+                    padding: const EdgeInsets.symmetric(horizontal: 32, vertical: 14),
+                    decoration: BoxDecoration(
+                      color: const Color(0xFFD4A84B),
+                      borderRadius: BorderRadius.circular(12),
+                      boxShadow: const [
+                        BoxShadow(
+                          color: Color(0x33D4A84B),
+                          blurRadius: 8,
+                          offset: Offset(0, 4),
+                        ),
+                      ],
+                    ),
+                    child: const Text(
+                      '重新尝试',
+                      style: TextStyle(
+                        fontSize: 16,
+                        fontFamily: 'Inter',
+                        fontWeight: FontWeight.w700,
+                        color: Colors.white,
+                      ),
+                    ),
+                  ),
+                ),
+              ],
             ),
-          ],
+          ),
         ),
       ),
     );
   }
 
-  /// 构建内容
-  Widget _buildContent() {
+  /// 构建内容（带占位数据）
+  Widget _buildContentWithPlaceholder() {
+    // 使用占位数据或真实数据
+    final displayWords = _mnemonicWords.isNotEmpty
+        ? _mnemonicWords
+        : List.generate(12, (i) => '******');
+    final displayKava = _kavaAddress ?? '0x••••••••••••••••••••';
+    final displayDst = _dstAddress ?? '0x••••••••••••••••••••';
+    final displayBsc = _bscAddress ?? '0x••••••••••••••••••••';
+
     return SingleChildScrollView(
       padding: const EdgeInsets.symmetric(horizontal: 16),
       child: Column(
         children: [
           const SizedBox(height: 8),
-          // 助记词卡片
-          if (_mnemonicWords.isNotEmpty) _buildMnemonicCard(),
+          // 助记词卡片 (使用占位或真实数据)
+          _buildMnemonicCardWithData(displayWords),
           const SizedBox(height: 16),
           // 警告提示
           _buildWarningCard(),
           const SizedBox(height: 16),
-          // 钱包地址卡片
-          _buildAddressCard(),
+          // 钱包地址卡片 (使用占位或真实数据)
+          _buildAddressCardWithData(displayKava, displayDst, displayBsc),
           const SizedBox(height: 16),
         ],
       ),
@@ -710,6 +906,329 @@ ${DateTime.now().toString()}
     );
   }
 
+  /// 构建助记词卡片（带数据参数）
+  Widget _buildMnemonicCardWithData(List<String> words) {
+    final isPlaceholder = words.isNotEmpty && words[0] == '******';
+    return Container(
+      width: double.infinity,
+      padding: const EdgeInsets.all(16),
+      decoration: BoxDecoration(
+        color: const Color(0xFFFFFDF5),
+        borderRadius: BorderRadius.circular(16),
+        boxShadow: const [
+          BoxShadow(
+            color: Color(0x0D000000),
+            blurRadius: 4,
+            offset: Offset(0, 2),
+          ),
+        ],
+      ),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          // 标题和操作按钮
+          Row(
+            mainAxisAlignment: MainAxisAlignment.spaceBetween,
+            children: [
+              const Text(
+                '您的助记词',
+                style: TextStyle(
+                  fontSize: 18,
+                  fontFamily: 'Inter',
+                  fontWeight: FontWeight.w700,
+                  height: 1.25,
+                  letterSpacing: -0.27,
+                  color: Color(0xFF5D4037),
+                ),
+              ),
+              // 仅在非占位状态时显示操作按钮
+              if (!isPlaceholder)
+                Row(
+                  children: [
+                    // 显示/隐藏按钮
+                    GestureDetector(
+                      onTap: _toggleVisibility,
+                      child: Container(
+                        padding: const EdgeInsets.all(4),
+                        child: Icon(
+                          _isHidden ? Icons.visibility : Icons.visibility_off,
+                          color: const Color(0xFF8B7355),
+                          size: 22,
+                        ),
+                      ),
+                    ),
+                    const SizedBox(width: 12),
+                    // 下载按钮
+                    GestureDetector(
+                      onTap: _isDownloading ? null : _downloadMnemonic,
+                      child: Container(
+                        padding: const EdgeInsets.all(4),
+                        child: _isDownloading
+                            ? const SizedBox(
+                                width: 22,
+                                height: 22,
+                                child: CircularProgressIndicator(
+                                  strokeWidth: 2,
+                                  valueColor: AlwaysStoppedAnimation<Color>(
+                                    Color(0xFF8B7355),
+                                  ),
+                                ),
+                              )
+                            : const Icon(
+                                Icons.file_download_outlined,
+                                color: Color(0xFF8B7355),
+                                size: 22,
+                              ),
+                      ),
+                    ),
+                  ],
+                ),
+            ],
+          ),
+          const SizedBox(height: 20),
+          // 助记词网格
+          _buildMnemonicGridWithData(words),
+          const SizedBox(height: 20),
+          // 复制全部按钮（仅在非占位状态时可用）
+          _buildCopyAllButtonWithState(!isPlaceholder),
+        ],
+      ),
+    );
+  }
+
+  /// 构建助记词网格（带数据参数）
+  Widget _buildMnemonicGridWithData(List<String> words) {
+    return Column(
+      children: [
+        for (int row = 0; row < 4; row++)
+          Padding(
+            padding: const EdgeInsets.symmetric(vertical: 8),
+            child: Row(
+              children: [
+                for (int col = 0; col < 3; col++)
+                  Expanded(
+                    child: _buildMnemonicWordWithData(
+                      row * 3 + col + 1,
+                      words.length > row * 3 + col ? words[row * 3 + col] : '',
+                    ),
+                  ),
+              ],
+            ),
+          ),
+      ],
+    );
+  }
+
+  /// 构建单个助记词项（带数据参数）
+  Widget _buildMnemonicWordWithData(int index, String word) {
+    final isPlaceholder = word == '******';
+    return Row(
+      mainAxisSize: MainAxisSize.min,
+      children: [
+        // 序号
+        Text(
+          '$index.',
+          style: TextStyle(
+            fontSize: 14,
+            fontFamily: 'Inter',
+            fontWeight: FontWeight.w500,
+            height: 1.43,
+            color: isPlaceholder
+                ? const Color(0x668B7355)
+                : const Color(0xCC8B7355),
+          ),
+        ),
+        const SizedBox(width: 6),
+        // 单词
+        Text(
+          _isHidden && !isPlaceholder ? '******' : word,
+          style: TextStyle(
+            fontSize: 15,
+            fontFamily: 'Inter',
+            fontWeight: FontWeight.w600,
+            height: 1.5,
+            color: isPlaceholder
+                ? const Color(0x665D4037)
+                : const Color(0xFF5D4037),
+          ),
+        ),
+      ],
+    );
+  }
+
+  /// 构建复制全部按钮（带状态）
+  Widget _buildCopyAllButtonWithState(bool enabled) {
+    return GestureDetector(
+      onTap: enabled ? _copyAllMnemonic : null,
+      child: Container(
+        width: double.infinity,
+        height: 44,
+        decoration: BoxDecoration(
+          color: enabled
+              ? const Color(0xFFF5ECD9)
+              : const Color(0xFFE8E0D0),
+          borderRadius: BorderRadius.circular(10),
+        ),
+        child: Center(
+          child: Text(
+            '复制全部',
+            style: TextStyle(
+              fontSize: 16,
+              fontFamily: 'Inter',
+              fontWeight: FontWeight.w600,
+              height: 1.5,
+              color: enabled
+                  ? const Color(0xFF8B7355)
+                  : const Color(0x668B7355),
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+
+  /// 构建钱包地址卡片（带数据参数）
+  Widget _buildAddressCardWithData(String kava, String dst, String bsc) {
+    final isPlaceholder = kava.contains('••••');
+    return Container(
+      width: double.infinity,
+      decoration: BoxDecoration(
+        color: const Color(0xFFFFFDF5),
+        borderRadius: BorderRadius.circular(16),
+        boxShadow: const [
+          BoxShadow(
+            color: Color(0x0D000000),
+            blurRadius: 4,
+            offset: Offset(0, 2),
+          ),
+        ],
+      ),
+      child: Column(
+        children: [
+          _buildAddressItemWithData(
+            iconWidget: _buildChainIcon(),
+            label: 'KAVA 地址',
+            address: kava,
+            showBorder: true,
+            isPlaceholder: isPlaceholder,
+          ),
+          _buildAddressItemWithData(
+            iconWidget: _buildChainIcon(),
+            label: 'DST 地址',
+            address: dst,
+            showBorder: true,
+            isPlaceholder: isPlaceholder,
+          ),
+          _buildAddressItemWithData(
+            iconWidget: _buildChainIcon(),
+            label: 'BSC 地址',
+            address: bsc,
+            showBorder: true,
+            isPlaceholder: isPlaceholder,
+          ),
+          _buildAddressItemWithData(
+            iconWidget: _buildSequenceIcon(),
+            label: '序列号',
+            address: widget.userSerialNum.toString(),
+            showBorder: false,
+            isPlaceholder: false,
+          ),
+        ],
+      ),
+    );
+  }
+
+  /// 构建地址项（带占位状态）
+  Widget _buildAddressItemWithData({
+    required Widget iconWidget,
+    required String label,
+    required String address,
+    required bool showBorder,
+    required bool isPlaceholder,
+  }) {
+    return Container(
+      padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 14),
+      decoration: BoxDecoration(
+        border: showBorder
+            ? const Border(
+                bottom: BorderSide(
+                  color: Color(0x1A5D4037),
+                  width: 1,
+                ),
+              )
+            : null,
+      ),
+      child: Row(
+        children: [
+          // 图标
+          iconWidget,
+          const SizedBox(width: 14),
+          // 标签和地址
+          Expanded(
+            child: Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text(
+                  label,
+                  style: TextStyle(
+                    fontSize: 16,
+                    fontFamily: 'Inter',
+                    fontWeight: FontWeight.w600,
+                    height: 1.5,
+                    color: isPlaceholder
+                        ? const Color(0x995D4037)
+                        : const Color(0xFF5D4037),
+                  ),
+                ),
+                const SizedBox(height: 2),
+                Text(
+                  _formatAddress(address),
+                  style: TextStyle(
+                    fontSize: 14,
+                    fontFamily: 'Inter',
+                    height: 1.5,
+                    color: isPlaceholder
+                        ? const Color(0x66756452)
+                        : const Color(0x99756452),
+                  ),
+                ),
+              ],
+            ),
+          ),
+          // 复制按钮（仅在非占位状态时可用）
+          if (!isPlaceholder)
+            GestureDetector(
+              onTap: () => _copyAddress(address, label),
+              child: Container(
+                padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 6),
+                child: const Row(
+                  mainAxisSize: MainAxisSize.min,
+                  children: [
+                    Icon(
+                      Icons.copy_rounded,
+                      color: Color(0xCC8B7355),
+                      size: 16,
+                    ),
+                    SizedBox(width: 4),
+                    Text(
+                      '复制',
+                      style: TextStyle(
+                        fontSize: 14,
+                        fontFamily: 'Inter',
+                        fontWeight: FontWeight.w500,
+                        height: 1.5,
+                        color: Color(0xCC8B7355),
+                      ),
+                    ),
+                  ],
+                ),
+              ),
+            ),
+        ],
+      ),
+    );
+  }
+
   /// 构建警告卡片
   Widget _buildWarningCard() {
     return Container(
@@ -733,7 +1252,7 @@ ${DateTime.now().toString()}
     );
   }
 
-  /// 构建钱包地址卡片
+  /// 构建钱包地址卡片 (旧方法，保留向后兼容)
   Widget _buildAddressCard() {
     return Container(
       width: double.infinity,