feat(响应式布局): 优化移动端头部导航和用户信息展示

调整媒体查询断点至480px和768px，优化小屏幕下的布局
添加移动端导航菜单显示逻辑和用户信息展示
新增关闭按钮功能及登录状态判断

css/public.css

@@ -1773,6 +1773,15 @@ body {
 .head-top .post-list .post-item:not(:last-child) {
   margin-right: 10px;
 }
+.head-top .head-more {
+  display: none;
+  padding: 5px;
+}
+@media screen and (max-width: 480px) {
+  .head-top .head-more {
+    display: flex;
+  }
+}
 .hot-tag {
   background-color: #ffffff;
   border: 1px solid #e9eef2;
@@ -2009,6 +2018,7 @@ td {
 .head-pop .head-more-pop .head-more-userinfo .head-more-right {
   width: 84px;
   height: 30px;
+  display: none;
 }
 .head-pop .head-more-pop .head-more-userinfo .head-more-right .information-box {
   position: relative;