feat: home page logout stays + wider PC layout

- logout() on home/root page: Auth.reset() only (clear state, refresh
  top bar), no redirect to login; other pages still go to login
- home page container: width:min(50vw+300px, 1440px, 96vw) replaces
  fixed max-width:800px - PC wide screens use at least half viewport,
  mobile near full width

public/js/app.js

@@ -83,7 +83,16 @@ const App = {
   },
 
   afterLogin() { location.hash = '#/dashboard'; },
-  logout() { Auth.logout(); },
+  logout() {
+    // 首页/根路径为公开页: 退出仅清除登录态, 停留当前页刷新顶栏; 其他页面才回登录页
+    const page = (location.hash || '#/home').replace('#/', '').split('/')[0];
+    if (page === 'home' || page === '') {
+      Auth.reset();
+      this.updateTopAuth();
+    } else {
+      Auth.logout();
+    }
+  },
   closeModal() { document.getElementById('modal-overlay').classList.add('hidden'); },
   navigate(page, param) { location.hash = `#/${page}` + (param ? `/${param}` : ''); },
 

public/js/pages/home.js

@@ -20,7 +20,8 @@
 const HomePage = {
   async render(tab) {
     const t = tab || 'report';
-    return `<div id="home-content" style="max-width:800px;margin:0 auto;padding:30px 0">
+    // PC 宽屏自适应: 至少占视口一半, 大屏上限 1440px; 手机端接近全宽
+    return `<div id="home-content" style="width:min(50vw + 300px, 1440px, 96vw);margin:0 auto;padding:30px 20px">
       <div class="tab-nav">
         <button class="${t==='report'?'active':''}" data-tab="report"><i class="fas fa-flag"></i> 举报</button>
         <button class="${t==='suggestion'?'active':''}" data-tab="suggestion"><i class="fas fa-lightbulb"></i> 建议</button>