feat(ui): 优化所有页面使用现代设计系统

- 使用 AppSpacing 替换硬编码间距
- 使用 AppRadius 替换硬编码圆角
- 使用 withValues(alpha:) 替换 withOpacity
- 优化 login_page, home_page, market_page, trade_page, asset_page, mine_page

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

flutter_monisuo/lib/ui/pages/home/home_page.dart

@@ -2,6 +2,8 @@ import 'package:flutter/material.dart';
 import 'package:shadcn_ui/shadcn_ui.dart';
 import 'package:provider/provider.dart';
 import '../../../core/constants/app_colors.dart';
+import '../../../core/theme/app_color_scheme.dart';
+import '../../../core/theme/app_spacing.dart';
 import '../../../providers/asset_provider.dart';
 import '../../../providers/auth_provider.dart';
 import '../../shared/ui_constants.dart';
@@ -44,22 +46,22 @@ class _HomePageState extends State<HomePage> with AutomaticKeepAliveClientMixin
             color: theme.colorScheme.primary,
             child: SingleChildScrollView(
               physics: const AlwaysScrollableScrollPhysics(),
-              padding: const EdgeInsets.all(16),
+              padding: AppSpacing.pagePadding,
               child: Column(
                 crossAxisAlignment: CrossAxisAlignment.start,
                 children: [
-                  const SizedBox(height: 8),
+                  SizedBox(height: AppSpacing.sm),
                   _Header(),
-                  const SizedBox(height: 20),
+                  SizedBox(height: AppSpacing.lg + AppSpacing.sm),
                   _AssetOverviewCard(overview: provider.overview),
-                  const SizedBox(height: 16),
+                  SizedBox(height: AppSpacing.md),
                   _QuickActions(
                     onDeposit: _showDeposit,
                     onWithdraw: _showWithdraw,
                     onTransfer: _showTransfer,
                     onTrade: _navigateToTrade,
                   ),
-                  const SizedBox(height: 24),
+                  SizedBox(height: AppSpacing.lg),
                   _HoldingsList(holdings: provider.holdings),
                 ],
               ),
@@ -96,14 +98,14 @@ class _HomePageState extends State<HomePage> with AutomaticKeepAliveClientMixin
                 keyboardType: const TextInputType.numberWithOptions(decimal: true),
                 validator: Validators.amount,
               ),
-              const SizedBox(height: 12),
+              SizedBox(height: AppSpacing.sm + AppSpacing.xs),
               ShadInputFormField(
                 id: 'address',
                 placeholder: const Text('请输入提现地址'),
                 controller: addressController,
                 validator: (v) => Validators.required(v, '提现地址'),
               ),
-              const SizedBox(height: 12),
+              SizedBox(height: AppSpacing.sm + AppSpacing.xs),
               ShadInputFormField(
                 id: 'contact',
                 placeholder: const Text('联系方式(可选)'),
@@ -187,7 +189,7 @@ class _Header extends StatelessWidget {
         return Row(
           children: [
             _Avatar(text: user?.avatarText),
-            const SizedBox(width: 12),
+            SizedBox(width: AppSpacing.sm + AppSpacing.xs),
             Expanded(
               child: Column(
                 crossAxisAlignment: CrossAxisAlignment.start,
@@ -196,7 +198,7 @@ class _Header extends StatelessWidget {
                     '你好，${user?.username ?? '用户'}',
                     style: theme.textTheme.large.copyWith(fontWeight: FontWeight.bold),
                   ),
-                  const SizedBox(height: 2),
+                  SizedBox(height: AppSpacing.xs),
                   Text('欢迎来到模拟所', style: theme.textTheme.muted),
                 ],
               ),
@@ -241,25 +243,25 @@ class _AssetOverviewCard extends StatelessWidget {
 
     return Container(
       width: double.infinity,
-      padding: const EdgeInsets.all(20),
+      padding: EdgeInsets.all(AppSpacing.lg + AppSpacing.sm),
       decoration: BoxDecoration(
         gradient: const LinearGradient(
           colors: AppColors.gradientColors,
           begin: Alignment.topLeft,
           end: Alignment.bottomRight,
         ),
-        borderRadius: BorderRadius.circular(16),
+        borderRadius: BorderRadius.circular(AppRadius.xl),
       ),
       child: Column(
         crossAxisAlignment: CrossAxisAlignment.start,
         children: [
           Text('总资产(USDT)', style: theme.textTheme.small.copyWith(color: Colors.white70)),
-          const SizedBox(height: 8),
+          SizedBox(height: AppSpacing.sm),
           Text(
             overview?.totalAsset ?? '0.00',
             style: theme.textTheme.h2.copyWith(color: Colors.white, fontWeight: FontWeight.bold),
           ),
-          const SizedBox(height: 20),
+          SizedBox(height: AppSpacing.lg + AppSpacing.sm),
           Row(
             mainAxisAlignment: MainAxisAlignment.spaceBetween,
             children: [
@@ -286,7 +288,7 @@ class _AssetItem extends StatelessWidget {
       crossAxisAlignment: CrossAxisAlignment.start,
       children: [
         Text(label, style: const TextStyle(fontSize: 12, color: Colors.white70)),
-        const SizedBox(height: 4),
+        SizedBox(height: AppSpacing.xs),
         Text(value, style: const TextStyle(fontSize: 18, fontWeight: FontWeight.w600, color: Colors.white)),
       ],
     );
@@ -310,14 +312,14 @@ class _QuickActions extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     return ShadCard(
-      padding: const EdgeInsets.all(16),
+      padding: AppSpacing.cardPadding,
       child: Row(
         mainAxisAlignment: MainAxisAlignment.spaceAround,
         children: [
-          _ActionButton(icon: LucideIcons.arrowDownToLine, text: '充值', color: AppColors.deposit, onTap: onDeposit),
-          _ActionButton(icon: LucideIcons.arrowUpFromLine, text: '提现', color: AppColors.withdraw, onTap: onWithdraw),
-          _ActionButton(icon: LucideIcons.arrowRightLeft, text: '划转', color: AppColors.trade, onTap: onTransfer),
-          _ActionButton(icon: LucideIcons.trendingUp, text: '交易', color: AppColors.trade, onTap: onTrade),
+          _ActionButton(icon: LucideIcons.arrowDownToLine, text: '充值', color: AppColorScheme.success, onTap: onDeposit),
+          _ActionButton(icon: LucideIcons.arrowUpFromLine, text: '提现', color: AppColorScheme.warning, onTap: onWithdraw),
+          _ActionButton(icon: LucideIcons.arrowRightLeft, text: '划转', color: AppColorScheme.info, onTap: onTransfer),
+          _ActionButton(icon: LucideIcons.trendingUp, text: '交易', color: AppColorScheme.info, onTap: onTrade),
         ],
       ),
     ).animate().fadeIn(duration: 500.ms, delay: 100.ms);
@@ -349,10 +351,10 @@ class _ActionButton extends StatelessWidget {
           Container(
             width: 48,
             height: 48,
-            decoration: BoxDecoration(color: color.withOpacity(0.15), shape: BoxShape.circle),
+            decoration: BoxDecoration(color: color.withValues(alpha: 0.15), shape: BoxShape.circle),
             child: Icon(icon, color: color, size: 22),
           ),
-          const SizedBox(height: 8),
+          SizedBox(height: AppSpacing.sm),
           Text(text, style: TextStyle(fontSize: 12, color: theme.colorScheme.foreground)),
         ],
       ),
@@ -371,7 +373,7 @@ class _HoldingsList extends StatelessWidget {
     final theme = ShadTheme.of(context);
 
     return ShadCard(
-      padding: const EdgeInsets.all(16),
+      padding: AppSpacing.cardPadding,
       child: Column(
         crossAxisAlignment: CrossAxisAlignment.start,
         children: [
@@ -382,7 +384,7 @@ class _HoldingsList extends StatelessWidget {
               Icon(LucideIcons.chevronRight, color: theme.colorScheme.mutedForeground, size: 20),
             ],
           ),
-          const SizedBox(height: 16),
+          SizedBox(height: AppSpacing.md),
           if (holdings.isEmpty)
             _EmptyHoldings()
           else
@@ -401,13 +403,13 @@ class _EmptyHoldings extends StatelessWidget {
 
     return Center(
       child: Padding(
-        padding: const EdgeInsets.all(32),
+        padding: EdgeInsets.all(AppSpacing.xl),
         child: Column(
           children: [
             Icon(LucideIcons.wallet, size: 48, color: theme.colorScheme.mutedForeground),
-            const SizedBox(height: 12),
+            SizedBox(height: AppSpacing.sm + AppSpacing.xs),
             Text('暂无持仓', style: theme.textTheme.muted),
-            const SizedBox(height: 4),
+            SizedBox(height: AppSpacing.xs),
             Text('快去交易吧~', style: theme.textTheme.muted.copyWith(fontSize: 12)),
           ],
         ),
@@ -452,7 +454,7 @@ class _HoldingItem extends StatelessWidget {
     final theme = ShadTheme.of(context);
 
     return Padding(
-      padding: const EdgeInsets.symmetric(vertical: 8),
+      padding: EdgeInsets.symmetric(vertical: AppSpacing.sm),
       child: Row(
         mainAxisAlignment: MainAxisAlignment.spaceBetween,
         children: [
@@ -466,7 +468,7 @@ class _HoldingItem extends StatelessWidget {
                   style: TextStyle(color: theme.colorScheme.primary, fontWeight: FontWeight.bold),
                 ),
               ),
-              const SizedBox(width: 12),
+              SizedBox(width: AppSpacing.sm + AppSpacing.xs),
               Column(
                 crossAxisAlignment: CrossAxisAlignment.start,
                 children: [
@@ -483,7 +485,7 @@ class _HoldingItem extends StatelessWidget {
               Text(
                 holding.formattedProfitRate,
                 style: TextStyle(
-                  color: holding.isProfit ? AppColors.up : AppColors.down,
+                  color: holding.isProfit ? AppColorScheme.up : AppColorScheme.down,
                   fontSize: 12,
                 ),
               ),