fix: 固定宽度布局 - 侧边栏 160px + 主内容 calc(100vw-160px) = 100vw

platform/frontend/index.html

@@ -89,7 +89,7 @@
               </div>
             </div>
           </div>
-          <div v-if="currentPage === 'topics'" style="margin-left: 160px; width: 100%; padding: 0 20px; box-sizing: border-box; overflow-x: auto;">
+          <div v-if="currentPage === 'topics'" style="margin-left: 160px; width: calc(100vw - 160px); padding: 0 20px; box-sizing: border-box; overflow-x: auto;">
             <div class="flex justify-between items-center mb-6" style="width: 100%;"><h2 class="text-2xl font-bold text-gray-800">📋 选题管理</h2></div>
             <div class="card mb-6" style="display: inline-block; min-width: fit-content;"><div class="flex flex-wrap gap-2 items-center">
               <el-button type="primary" size="small" @click="refreshAll">🔄 批量刷新</el-button>
@@ -104,7 +104,7 @@
               <el-tag size="large" :type="filterStatus === '待发布' ? 'primary' : ''" @click="filterStatus = '待发布'">待发布 ({{ countByStatus('待发布') }})</el-tag>
               <el-tag size="large" :type="filterStatus === '已发布' ? 'primary' : ''" @click="filterStatus = '已发布'">已发布 ({{ countByStatus('已发布') }})</el-tag>
             </div>
-            <div class="card" style="width: 100%; overflow-x: auto;">
+            <div class="card" style="width: 100%; overflow-x: auto; box-sizing: border-box;">
               <el-table :data="filteredTopics" style=" max-"> stripe v-loading="loadingTable" :row-key="topic => topic.id" @selection-change="selectedTopicIds = $event">
                 <el-table-column type="selection" width="55"></el-table-column>
                 <el-table-column prop="id" label="ID" width="70" fixed></el-table-column>