feat(mobile-app): 优化创建钱包页面UI

- 添加背景图片 onboarding_bg.jpg
- 移除重复的logo和标题（背景图已包含）
- 添加白色半透明卡片背景提高文字可读性
- 调整颜色主题为绿色系匹配背景
- 修改认种确认弹窗标题为"一旦确认，无法更改"

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/mobile-app/lib/features/auth/presentation/pages/onboarding_page.dart

@@ -257,31 +257,28 @@ class _OnboardingPageState extends ConsumerState<OnboardingPage> {
       body: Container(
         width: double.infinity,
         height: double.infinity,
-        // 渐变背景 - 从浅米色到金黄色
+        // 背景图片
         decoration: const BoxDecoration(
-          gradient: LinearGradient(
-            begin: Alignment.topCenter,
-            end: Alignment.bottomCenter,
-            colors: [
-              Color(0xFFFFF5E6), // 浅米色
-              Color(0xFFFFE4B5), // 金黄色
-            ],
+          image: DecorationImage(
+            image: AssetImage('assets/images/backgrounds/onboarding_bg.jpg'),
+            fit: BoxFit.cover,
           ),
         ),
         child: SafeArea(
           child: Padding(
-            padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 15),
+            padding: const EdgeInsets.symmetric(horizontal: 20, vertical: 15),
             child: Column(
               children: [
-                // 顶部 Logo 和标题区域
+                // 顶部返回按钮
                 _buildHeader(),
-                const SizedBox(height: 48),
+                // 留出空间给背景图的 logo
+                const Spacer(flex: 3),
                 // 创建账户说明区域
                 _buildDescription(),
-                const Spacer(),
+                const SizedBox(height: 16),
                 // 底部操作区域
                 _buildActionSection(),
-                const SizedBox(height: 9),
+                const Spacer(flex: 1),
               ],
             ),
           ),
@@ -297,136 +294,122 @@ class _OnboardingPageState extends ConsumerState<OnboardingPage> {
     context.go(RoutePaths.guide, extra: 4);
   }
 
-  /// 构建顶部 Logo 和标题
+  /// 构建顶部返回按钮
   Widget _buildHeader() {
-    return Column(
-      children: [
-        // 返回按钮行 - 仅在账号未创建时显示
-        SizedBox(
-          height: 32,
-          child: (!_isLoading && !_isAccountCreated)
-              ? Align(
-                  alignment: Alignment.centerLeft,
-                  child: GestureDetector(
-                    onTap: _goBackToGuide,
-                    behavior: HitTestBehavior.opaque,
-                    child: const Padding(
-                      padding: EdgeInsets.symmetric(vertical: 4),
-                      child: Row(
-                        mainAxisSize: MainAxisSize.min,
-                        children: [
-                          Icon(
-                            Icons.arrow_back_ios,
-                            size: 18,
-                            color: Color(0xFF5D4037),
-                          ),
-                          SizedBox(width: 4),
-                          Text(
-                            '返回',
-                            style: TextStyle(
-                              fontSize: 14,
-                              fontFamily: 'Inter',
-                              fontWeight: FontWeight.w500,
-                              color: Color(0xFF5D4037),
-                            ),
-                          ),
-                        ],
-                      ),
-                    ),
+    return SizedBox(
+      height: 32,
+      child: (!_isLoading && !_isAccountCreated)
+          ? Align(
+              alignment: Alignment.centerLeft,
+              child: GestureDetector(
+                onTap: _goBackToGuide,
+                behavior: HitTestBehavior.opaque,
+                child: Container(
+                  padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
+                  decoration: BoxDecoration(
+                    color: Colors.white.withValues(alpha: 0.9),
+                    borderRadius: BorderRadius.circular(16),
                   ),
-                )
-              : null,
-        ),
-        // Logo 容器
-        Container(
-          width: 100,
-          height: 80,
-          decoration: BoxDecoration(
-            color: Colors.white,
-            borderRadius: BorderRadius.circular(8),
-            boxShadow: [
-              BoxShadow(
-                color: Colors.black.withValues(alpha: 0.05),
-                blurRadius: 10,
-                offset: const Offset(0, 2),
+                  child: const Row(
+                    mainAxisSize: MainAxisSize.min,
+                    children: [
+                      Icon(
+                        Icons.arrow_back_ios,
+                        size: 16,
+                        color: Color(0xFF2E7D32),
+                      ),
+                      SizedBox(width: 4),
+                      Text(
+                        '返回',
+                        style: TextStyle(
+                          fontSize: 14,
+                          fontFamily: 'Inter',
+                          fontWeight: FontWeight.w600,
+                          color: Color(0xFF2E7D32),
+                        ),
+                      ),
+                    ],
+                  ),
+                ),
               ),
-            ],
-          ),
-          child: const Center(
-            child: Text(
-              'ap',
-              style: TextStyle(
-                fontSize: 32,
-                fontWeight: FontWeight.w600,
-                color: Color(0xFF2E7D32), // 绿色
-              ),
-            ),
-          ),
-        ),
-        const SizedBox(height: 24),
-        // 应用标题
-        const Text(
-          '榴莲皇后',
-          style: TextStyle(
-            fontSize: 32,
-            fontFamily: 'Inter',
-            fontWeight: FontWeight.w700,
-            height: 1.25,
-            color: Color(0xFF5D4037), // 深棕色
-          ),
-        ),
-      ],
+            )
+          : null,
     );
   }
 
   /// 构建创建账户说明区域
   Widget _buildDescription() {
-    return Column(
-      children: [
-        // 标题
-        const Text(
-          '创建账户',
-          style: TextStyle(
-            fontSize: 22,
-            fontFamily: 'Inter',
-            fontWeight: FontWeight.w700,
-            height: 1.25,
-            letterSpacing: -0.33,
-            color: Color(0xFF5D4037),
+    return Container(
+      padding: const EdgeInsets.all(20),
+      decoration: BoxDecoration(
+        color: Colors.white.withValues(alpha: 0.95),
+        borderRadius: BorderRadius.circular(16),
+        boxShadow: [
+          BoxShadow(
+            color: Colors.black.withValues(alpha: 0.1),
+            blurRadius: 10,
+            offset: const Offset(0, 4),
           ),
-        ),
-        const SizedBox(height: 16),
-        // 说明文字
-        const Padding(
-          padding: EdgeInsets.symmetric(horizontal: 20),
-          child: Text(
+        ],
+      ),
+      child: const Column(
+        children: [
+          // 标题
+          Text(
+            '创建账户',
+            style: TextStyle(
+              fontSize: 22,
+              fontFamily: 'Inter',
+              fontWeight: FontWeight.w700,
+              height: 1.25,
+              letterSpacing: -0.33,
+              color: Color(0xFF2E7D32),
+            ),
+          ),
+          SizedBox(height: 12),
+          // 说明文字
+          Text(
             '我们将为你创建三个链的钱包地址：KAVA / DST / BSC，同时生成唯一序列号用于推荐与权益。',
             style: TextStyle(
-              fontSize: 16,
+              fontSize: 15,
               fontFamily: 'Inter',
               height: 1.5,
-              color: Color(0xFF5D4037),
+              color: Color(0xFF424242),
             ),
             textAlign: TextAlign.center,
           ),
-        ),
-      ],
+        ],
+      ),
     );
   }
 
   /// 构建底部操作区域
   Widget _buildActionSection() {
-    return Column(
-      children: [
-        // 生成钱包按钮
-        _buildCreateButton(),
-        const SizedBox(height: 20),
-        // 用户协议勾选
-        _buildAgreementCheckbox(),
-        const SizedBox(height: 24),
-        // 导入助记词链接
-        _buildImportLink(),
-      ],
+    return Container(
+      padding: const EdgeInsets.all(20),
+      decoration: BoxDecoration(
+        color: Colors.white.withValues(alpha: 0.95),
+        borderRadius: BorderRadius.circular(16),
+        boxShadow: [
+          BoxShadow(
+            color: Colors.black.withValues(alpha: 0.1),
+            blurRadius: 10,
+            offset: const Offset(0, 4),
+          ),
+        ],
+      ),
+      child: Column(
+        children: [
+          // 生成钱包按钮
+          _buildCreateButton(),
+          const SizedBox(height: 16),
+          // 用户协议勾选
+          _buildAgreementCheckbox(),
+          const SizedBox(height: 16),
+          // 导入助记词链接
+          _buildImportLink(),
+        ],
+      ),
     );
   }
 
@@ -532,8 +515,8 @@ class _OnboardingPageState extends ConsumerState<OnboardingPage> {
                 _isAgreed = value ?? false;
               });
             },
-            activeColor: const Color(0xFFD4AF37),
-            side: const BorderSide(color: Color(0xFF5D4037)),
+            activeColor: const Color(0xFF2E7D32),
+            side: const BorderSide(color: Color(0xFF757575)),
             shape: RoundedRectangleBorder(
               borderRadius: BorderRadius.circular(4),
             ),
@@ -549,18 +532,18 @@ class _OnboardingPageState extends ConsumerState<OnboardingPage> {
                 fontFamily: 'Inter',
                 fontWeight: FontWeight.w500,
                 height: 1.43,
-                color: Color(0xFF5D4037),
+                color: Color(0xFF424242),
               ),
               children: [
                 const TextSpan(text: '我已阅读并同意 '),
                 TextSpan(
                   text: '《用户协议》',
-                  style: const TextStyle(color: Color(0xFFD4AF37)),
+                  style: const TextStyle(color: Color(0xFF2E7D32)),
                   recognizer: TapGestureRecognizer()..onTap = _showUserAgreement,
                 ),
                 TextSpan(
                   text: '《隐私政策》',
-                  style: const TextStyle(color: Color(0xFFD4AF37)),
+                  style: const TextStyle(color: Color(0xFF2E7D32)),
                   recognizer: TapGestureRecognizer()..onTap = _showPrivacyPolicy,
                 ),
               ],
@@ -580,9 +563,9 @@ class _OnboardingPageState extends ConsumerState<OnboardingPage> {
         style: TextStyle(
           fontSize: 14,
           fontFamily: 'Inter',
-          fontWeight: FontWeight.w500,
+          fontWeight: FontWeight.w600,
           height: 1.43,
-          color: Color(0xFFD4AF37),
+          color: Color(0xFF2E7D32),
         ),
       ),
     );

frontend/mobile-app/lib/features/planting/presentation/widgets/planting_confirm_dialog.dart

@@ -196,7 +196,7 @@ class _PlantingConfirmDialogState extends State<PlantingConfirmDialog> {
   /// 构建标题
   Widget _buildTitle() {
     return const Text(
-      '最后确认！不可修改！',
+      '一旦确认，无法更改',
       style: TextStyle(
         fontSize: 22,
         fontFamily: 'Inter',