fix(layout): adjust main content overflow and font stack configuration

- Change main content container overflow from 'auto' to 'hidden' in MainLayout.vue
- Update font stack in theme.css to include additional Chinese fonts and reorder priority
- Remove max-width constraint from profile container in Profile.vue for better responsiveness

frontend/app/web-gold/src/layouts/MainLayout.vue

@@ -12,7 +12,7 @@ import SidebarNav from '@/components/SidebarNav.vue'
     <TopNav />
     <div class="flex flex-1 pt-[70px]">
       <SidebarNav />
-      <main class="flex-1 h-[calc(100vh-70px)] overflow-auto">
+      <main class="flex-1 h-[calc(100vh-70px)] overflow-hidden">
         <RouterView v-slot="{ Component }">
           <keep-alive>
             <component :is="Component" />

frontend/app/web-gold/src/theme.css

@@ -129,7 +129,7 @@
   /* ========================================
      字体系统
      ======================================== */
-  --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
+  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Microsoft ZhengHei", "Noto Sans SC", "Heiti SC", -apple-system, BlinkMacSystemFont, sans-serif;
   --font-serif: ui-serif, Georgia, Cambria, "Times New Roman", Times, serif;
   --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, monospace;
   --font-family: var(--font-sans);

frontend/app/web-gold/src/views/user/Profile.vue

@@ -386,7 +386,6 @@ onMounted(async () => {
 <style scoped>
 .profile-container {
   padding: var(--space-6);
-  max-width: 1200px;
   margin: 0 auto;
 }