refactor: redesign Profile page, fix navigation & interaction logic

Profile page:
- Add page title '我的账户' in settings-section h2
- Restructure points section: horizontal action buttons (充值/明细/定价)
- Remove '产品定价' from menu list (already in points section)
- Remove '更多' heading

Interaction fixes:
- Profile logout now uses onNavigate('logout') → App.tsx ConfirmModal
- Sidebar dropdown: only '我的账户' + '退出登录' (others go through Profile)
- Add back button to usage-detail / system-update / about-us → navigate to profile
- content-management click: only expand/collapse, no auto-navigate to first child

CSS:
- Add --bg-secondary / --bg-tertiary to variables.css
- Add page-back-btn CSS class
- Convert profile-points-actions to horizontal row layout

tauri-app/src/components/Layout/Sidebar.tsx

@@ -35,9 +35,6 @@ interface SidebarProps {
 
 const userMenuItems = [
   { id: 'profile', label: '我的账户' },
-  { id: 'usage-detail', label: '使用明细' },
-  { id: 'system-update', label: '系统设置' },
-  { id: 'about-us', label: '关于我们' },
 ];
 
 export default function Sidebar({ currentPath, onNavigate }: SidebarProps) {
@@ -83,10 +80,6 @@ export default function Sidebar({ currentPath, onNavigate }: SidebarProps) {
   const handleClick = (item: NavItem) => {
     if (item.children) {
       toggleExpand(item.id);
-      // Navigate to first child
-      if (!expandedItems.has(item.id)) {
-        onNavigate(item.children[0].id);
-      }
     } else {
       onNavigate(item.id);
     }

tauri-app/src/pages/ContentManagement/ContentManagement.css

@@ -475,7 +475,7 @@
 
 .profile-points-section {
   display: flex;
-  align-items: flex-end;
+  flex-direction: column;
   gap: var(--spacing-lg);
   padding: 20px 28px;
 }
@@ -525,14 +525,14 @@
   color: var(--text-tertiary);
 }
 
-.profile-points-actions {
+.profile-points-actions-row {
   display: flex;
-  flex-direction: column;
-  gap: 10px;
+  gap: var(--spacing-sm);
+  flex-wrap: wrap;
 }
 
-.profile-points-actions .btn {
-  padding: 10px 24px;
+.profile-points-actions-row .btn {
+  padding: 10px 20px;
   font-size: var(--font-sm);
   white-space: nowrap;
 }
@@ -754,6 +754,32 @@
   overflow: hidden;
 }
 
+/* ── 页面返回按钮 ── */
+.page-back-btn {
+  display: inline-flex;
+  align-items: center;
+  gap: 6px;
+  padding: var(--spacing-sm) var(--spacing-md);
+  border: none;
+  background: transparent;
+  color: var(--text-secondary);
+  font-size: var(--font-sm);
+  font-family: inherit;
+  cursor: pointer;
+  border-radius: var(--radius-md);
+  transition: all var(--transition-fast);
+  margin-bottom: var(--spacing-sm);
+}
+
+.page-back-btn:hover {
+  color: var(--primary);
+  background: var(--bg-hover);
+}
+
+.page-back-btn svg {
+  flex-shrink: 0;
+}
+
 .profile-edit-wrap {
   display: flex;
   align-items: center;

tauri-app/src/pages/Profile/Profile.tsx

@@ -38,12 +38,6 @@ const FileTextIcon = () => (
   </svg>
 );
 
-const DollarSignIcon = () => (
-  <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
-    <line x1="12" y1="1" x2="12" y2="23" /><path d="M17 5H9.5a3.5 3.5 0 0 0 0 7h5a3.5 3.5 0 0 1 0 7H6" />
-  </svg>
-);
-
 const SettingsIcon = () => (
   <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
     <circle cx="12" cy="12" r="3" /><path d="M19.4 15a1.65 1.65 0 0 0 .33 1.82l.06.06a2 2 0 0 1 0 2.83 2 2 0 0 1-2.83 0l-.06-.06a1.65 1.65 0 0 0-1.82-.33 1.65 1.65 0 0 0-1 1.51V21a2 2 0 0 1-2 2 2 2 0 0 1-2-2v-.09A1.65 1.65 0 0 0 9 19.4a1.65 1.65 0 0 0-1.82.33l-.06.06a2 2 0 0 1-2.83 0 2 2 0 0 1 0-2.83l.06-.06a1.65 1.65 0 0 0 .33-1.82 1.65 1.65 0 0 0-1.51-1H3a2 2 0 0 1-2-2 2 2 0 0 1 2-2h.09A1.65 1.65 0 0 0 4.6 9a1.65 1.65 0 0 0-.33-1.82l-.06-.06a2 2 0 0 1 0-2.83 2 2 0 0 1 2.83 0l.06.06a1.65 1.65 0 0 0 1.82.33H9a1.65 1.65 0 0 0 1-1.51V3a2 2 0 0 1 2-2 2 2 0 0 1 2 2v.09a1.65 1.65 0 0 0 1 1.51 1.65 1.65 0 0 0 1.82-.33l.06-.06a2 2 0 0 1 2.83 0 2 2 0 0 1 0 2.83l-.06.06a1.65 1.65 0 0 0-.33 1.82V9a1.65 1.65 0 0 0 1.51 1H21a2 2 0 0 1 2 2 2 2 0 0 1-2 2h-.09a1.65 1.65 0 0 0-1.51 1z" />
@@ -77,7 +71,6 @@ const EditIcon = () => (
 export default function Profile() {
   const { navigate } = useNavigation();
   const authUser = useAuthStore((s) => s.user);
-  const logout = useAuthStore((s) => s.logout);
 
   const [user, setUser] = useState<UserProfile | null>(null);
   const [balance, setBalance] = useState<PointBalance | null>(null);
@@ -156,10 +149,8 @@ export default function Profile() {
     }
   };
 
-  const handleLogout = async () => {
-    if (!window.confirm('确定要退出登录吗？')) { return; }
-    await logout();
-    window.location.reload();
+  const handleLogout = () => {
+    navigate('logout');
   };
 
   const displayName = user?.nickname || authUser?.nickname || '用户';
@@ -168,14 +159,17 @@ export default function Profile() {
 
   const menuItems = [
     { label: '使用明细', icon: <FileTextIcon />, onClick: () => navigate('usage-detail') },
-    { label: '产品定价', icon: <DollarSignIcon />, onClick: handleOpenPricing },
     { label: '系统设置', icon: <SettingsIcon />, onClick: () => navigate('system-update') },
     { label: '关于我们', icon: <InfoIcon />, onClick: () => navigate('about-us') },
   ];
 
   return (
     <div className="settings-page">
-      {/* 个人资料卡片 */}
+      <div className="settings-section">
+        <h2>我的账户</h2>
+      </div>
+
+      {/* 个人信息 + 积分 */}
       <div className="card profile-card-flat">
         {/* 用户区 */}
         <div className="profile-user-section">
@@ -253,7 +247,7 @@ export default function Profile() {
             </div>
           </div>
 
-          <div className="profile-points-actions">
+          <div className="profile-points-actions-row">
             <button className="btn btn-primary btn-sm" onClick={() => setShowRechargeModal(true)}>
               积分充值
             </button>
@@ -273,9 +267,8 @@ export default function Profile() {
         </div>
       </div>
 
-      {/* 功能入口 */}
+      {/* 设置入口 */}
       <div className="profile-section-spaced">
-        <h3 className="profile-section-title">更多</h3>
         <div className="card profile-menu-list">
           {menuItems.map((item) => (
             <button key={item.label} className="profile-menu-item" onClick={item.onClick}>

tauri-app/src/pages/Profile/UsageDetail.tsx

@@ -1,4 +1,5 @@
 import { useEffect, useState, useCallback, useRef } from 'react';
+import { useNavigation } from '../../contexts/NavigationContext';
 import { pointsApi, type PointTransaction } from '../../api/modules/points';
 import DateRangePicker from '../../components/DatePicker/DateRangePicker';
 import '../ContentManagement/ContentManagement.css';
@@ -360,8 +361,16 @@ export default function UsageDetail() {
     return `${sign}${Math.abs(amount)}`;
   };
 
+  const { navigate } = useNavigation();
+
   return (
     <div className="settings-page">
+      <button className="page-back-btn" onClick={() => navigate('profile')}>
+        <svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
+          <polyline points="15 18 9 12 15 6" />
+        </svg>
+        返回
+      </button>
       <div className="settings-section">
         <h2>积分明细</h2>
 

tauri-app/src/pages/Settings/AboutUs.tsx

@@ -9,7 +9,7 @@ import { toast } from '../../store/uiStore';
 const CURRENT_VERSION = __APP_VERSION__;
 
 export default function AboutUs() {
-  const { appEnvironment } = useNavigation();
+  const { navigate, appEnvironment } = useNavigation();
   const [showModal, setShowModal] = useState(false);
 
   // 版本号连击检测
@@ -56,6 +56,12 @@ export default function AboutUs() {
 
   return (
     <div className="settings-page">
+      <button className="page-back-btn" onClick={() => navigate('profile')}>
+        <svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
+          <polyline points="15 18 9 12 15 6" />
+        </svg>
+        返回
+      </button>
       <div className="settings-section">
         <h2>关于我们</h2>
         <div className="card" style={{ padding: 0, overflow: 'hidden' }}>

tauri-app/src/pages/Settings/SystemUpdate.tsx

@@ -6,6 +6,7 @@
  */
 
 import { useState } from 'react';
+import { useNavigation } from '../../contexts/NavigationContext';
 import { check, type Update, type DownloadEvent } from '@tauri-apps/plugin-updater';
 import { relaunch } from '@tauri-apps/plugin-process';
 import '../ContentManagement/ContentManagement.css';
@@ -13,6 +14,7 @@ import '../ContentManagement/ContentManagement.css';
 const CURRENT_VERSION = __APP_VERSION__;
 
 export default function SystemUpdate() {
+  const { navigate } = useNavigation();
   const [checking, setChecking] = useState(false);
   const [checkResult, setCheckResult] = useState<'none' | 'latest' | 'available'>('none');
   const [updateInfo, setUpdateInfo] = useState<Update | null>(null);
@@ -107,6 +109,12 @@ export default function SystemUpdate() {
 
   return (
     <div className="settings-page">
+      <button className="page-back-btn" onClick={() => navigate('profile')}>
+        <svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
+          <polyline points="15 18 9 12 15 6" />
+        </svg>
+        返回
+      </button>
       <div className="settings-section">
         <h2>系统更新</h2>
         <div className="card" style={{ padding: 0, overflow: 'hidden' }}>