diff --git a/docs/project_context.md b/docs/project_context.md
index 4514ed2..52c706c 100644
--- a/docs/project_context.md
+++ b/docs/project_context.md
@@ -1,5 +1,12 @@
 # 项目上下文记录
 
+## 2026-05-19：优化数据管理导出入口和弹窗宽度
+
+- `frontend/src/composables/pageHeader.ts` 和 `frontend/src/AppShell.vue` 为页面顶部动作支持 Naive UI 下拉菜单，按钮内显示下拉箭头。
+- `frontend/src/components/DatabasePanel.vue` 将顶部“导出 CSV / 导出 XLSX”两个按钮合并为一个“导出”下拉按钮，点击后选择 CSV 或 XLSX 再进入对应表选择弹窗。
+- CSV 和 XLSX 导出弹窗改为固定 420px 内的响应式宽度，避免在宽屏下铺满整页；表选择列表增加边框和背景，视觉上更集中。
+- 已执行 `npm run build`，构建通过；构建只保留 Vite 原有大 chunk 提示。
+
 ## 2026-05-19：调整数据管理导出交互并支持多表 XLSX
 
 - `frontend/src/components/DatabasePanel.vue` 将导出入口移到页面顶部，并放在“删除全部表”按钮左侧；内容区工具栏只保留刷新、清空、删除当前表。
diff --git a/frontend/src/AppShell.vue b/frontend/src/AppShell.vue
index a40b57a..1008e46 100644
--- a/frontend/src/AppShell.vue
+++ b/frontend/src/AppShell.vue
@@ -42,6 +42,31 @@
             <span v-if="action.kind === 'text'" class="header-info-text">
               {{ actionLabel(action) }}
             </span>
+            <n-dropdown
+              v-else-if="actionDropdownOptions(action).length"
+              trigger="click"
+              :options="actionDropdownOptions(action)"
+              :disabled="actionDisabled(action)"
+              @select="runHeaderActionSelect(action)"
+            >
+              <n-button
+                size="small"
+                :type="action.type === 'default' ? undefined : action.type"
+                :tertiary="action.variant !== 'solid'"
+                :text="action.variant === 'text'"
+                :loading="actionLoading(action)"
+                :disabled="actionDisabled(action)"
+                :title="actionTitle(action)"
+              >
+                <template v-if="actionIcon(action)" #icon>
+                  <n-icon><component :is="actionIcon(action)" /></n-icon>
+                </template>
+                <span class="header-dropdown-label">
+                  <span>{{ actionLabel(action) }}</span>
+                  <n-icon class="header-dropdown-caret"><ChevronDownOutline /></n-icon>
+                </span>
+              </n-button>
+            </n-dropdown>
             <n-button
               v-else
               size="small"
@@ -97,8 +122,9 @@
 <script setup lang="ts">
 import { computed, h, onBeforeUnmount, onMounted, ref, watch, type Component } from 'vue';
 import { RouterView, useRoute, useRouter } from 'vue-router';
-import { useDialog, useMessage, type MenuOption, NIcon } from 'naive-ui';
+import { useDialog, useMessage, type DropdownOption, type MenuOption, NIcon } from 'naive-ui';
 import {
+  ChevronDownOutline,
   CloudUploadOutline,
   ConstructOutline,
   FileTrayFullOutline,
@@ -294,10 +320,20 @@ function actionDisabled(action: PageHeaderAction) {
   return resolveHeaderValue(action.disabled, false);
 }
 
+function actionDropdownOptions(action: PageHeaderAction) {
+  return resolveHeaderValue(action.dropdownOptions, []);
+}
+
 function runHeaderAction(action: PageHeaderAction) {
   void action.onClick?.();
 }
 
+function runHeaderActionSelect(action: PageHeaderAction) {
+  return (key: string | number, option: DropdownOption) => {
+    void action.onSelect?.(key, option);
+  };
+}
+
 function preventWindowFileDrop(event: DragEvent) {
   const types = Array.from(event.dataTransfer?.types || []);
   if (!types.includes('Files')) {
diff --git a/frontend/src/components/DatabasePanel.vue b/frontend/src/components/DatabasePanel.vue
index e2c911e..d7393ec 100644
--- a/frontend/src/components/DatabasePanel.vue
+++ b/frontend/src/components/DatabasePanel.vue
@@ -146,7 +146,13 @@
     </section>
   </div>
 
-  <n-modal v-model:show="csvDialogVisible" preset="card" class="table-export-modal" title="导出 CSV">
+  <n-modal
+    v-model:show="csvDialogVisible"
+    preset="card"
+    class="table-export-modal"
+    title="导出 CSV"
+    style="width: min(420px, calc(100vw - 32px))"
+  >
     <div class="export-dialog-body">
       <p class="export-dialog-hint">选择要导出的数据表。</p>
       <n-scrollbar class="export-table-options">
@@ -175,7 +181,13 @@
     </template>
   </n-modal>
 
-  <n-modal v-model:show="xlsxDialogVisible" preset="card" class="table-export-modal" title="导出 XLSX">
+  <n-modal
+    v-model:show="xlsxDialogVisible"
+    preset="card"
+    class="table-export-modal"
+    title="导出 XLSX"
+    style="width: min(420px, calc(100vw - 32px))"
+  >
     <div class="export-dialog-body">
       <p class="export-dialog-hint">选择一个或多个数据表，导出后会合并到同一个 XLSX 文件中。</p>
       <n-scrollbar class="export-table-options">
@@ -209,7 +221,7 @@
 import { computed, onActivated, onBeforeUnmount, onMounted, ref } from 'vue';
 import { onBeforeRouteLeave } from 'vue-router';
 import { useDialog, useMessage } from 'naive-ui';
-import type { DataTableColumns } from 'naive-ui';
+import type { DataTableColumns, DropdownOption } from 'naive-ui';
 import {
   ChevronForwardOutline,
   CloudDownloadOutline,
@@ -248,9 +260,14 @@ let tableLoadToken = 0;
 
 const totalPages = computed(() => Math.max(1, Math.ceil(total.value / pageSize.value)));
 const downloading = computed(() => Boolean(downloadingFormat.value));
-const csvExportButtonText = computed(() => (downloadingFormat.value === 'csv' ? '导出 CSV...' : '导出 CSV'));
-const xlsxExportButtonText = computed(() => (downloadingFormat.value === 'xlsx' ? '导出 XLSX...' : '导出 XLSX'));
+const exportButtonText = computed(() => (
+  downloadingFormat.value ? `导出 ${downloadingFormat.value.toUpperCase()}...` : '导出'
+));
 const exportDisabled = computed(() => loadingTables.value || tables.value.length === 0 || downloading.value);
+const exportOptions: DropdownOption[] = [
+  { label: 'CSV', key: 'csv' },
+  { label: 'XLSX', key: 'xlsx' }
+];
 const loadDataInfileText = computed(() => {
   if (testing.value || !databaseInfo.value) return '检测中';
   return databaseInfo.value.load_data_infile ? '可用' : '未启用';
@@ -281,24 +298,15 @@ onMounted(() => {
   setPageHeader({
     actions: [
       {
-        key: 'export-csv',
-        label: csvExportButtonText,
+        key: 'export',
+        label: exportButtonText,
         icon: CloudDownloadOutline,
         type: 'primary',
         variant: 'solid',
-        loading: computed(() => downloadingFormat.value === 'csv'),
+        loading: downloading,
         disabled: exportDisabled,
-        onClick: showCsvExportDialog
-      },
-      {
-        key: 'export-xlsx',
-        label: xlsxExportButtonText,
-        icon: CloudDownloadOutline,
-        type: 'primary',
-        variant: 'outline',
-        loading: computed(() => downloadingFormat.value === 'xlsx'),
-        disabled: exportDisabled,
-        onClick: showXlsxExportDialog
+        dropdownOptions: exportOptions,
+        onSelect: selectExportFormat
       },
       {
         key: 'drop-all-tables',
@@ -434,6 +442,17 @@ function changePageSize(value: number) {
   void loadTableData();
 }
 
+function selectExportFormat(key: string | number) {
+  if (key === 'csv') {
+    void showCsvExportDialog();
+    return;
+  }
+
+  if (key === 'xlsx') {
+    void showXlsxExportDialog();
+  }
+}
+
 async function showCsvExportDialog() {
   await loadTables();
   if (tables.value.length === 0) {
@@ -935,7 +954,7 @@ function formatCell(value: unknown): string {
 }
 
 .table-export-modal {
-  width: min(520px, calc(100vw - 32px));
+  max-width: calc(100vw - 32px);
 }
 
 .export-dialog-body {
@@ -952,7 +971,10 @@ function formatCell(value: unknown): string {
 
 .export-table-options {
   max-height: min(420px, 52vh);
-  padding: 6px 2px;
+  padding: 8px 10px;
+  background: var(--td-bg-color-component);
+  border: 1px solid var(--td-border-color-light);
+  border-radius: var(--td-radius-default);
 }
 
 .export-dialog-footer {
diff --git a/frontend/src/composables/pageHeader.ts b/frontend/src/composables/pageHeader.ts
index e57ff66..4006bda 100644
--- a/frontend/src/composables/pageHeader.ts
+++ b/frontend/src/composables/pageHeader.ts
@@ -1,4 +1,5 @@
 import { shallowReactive, unref, type Component, type Ref } from 'vue';
+import type { DropdownOption } from 'naive-ui';
 
 type HeaderValue<T> = T | Ref<T> | (() => T);
 
@@ -12,7 +13,9 @@ export interface PageHeaderAction {
   variant?: 'solid' | 'outline' | 'text';
   loading?: HeaderValue<boolean>;
   disabled?: HeaderValue<boolean>;
+  dropdownOptions?: HeaderValue<DropdownOption[]>;
   onClick?: () => void | Promise<void>;
+  onSelect?: (key: string | number, option: DropdownOption) => void | Promise<void>;
 }
 
 export const pageHeader = shallowReactive<{
diff --git a/frontend/src/styles.css b/frontend/src/styles.css
index df3e894..298ece9 100644
--- a/frontend/src/styles.css
+++ b/frontend/src/styles.css
@@ -342,6 +342,16 @@ select {
   white-space: nowrap;
 }
 
+.header-dropdown-label {
+  display: inline-flex;
+  align-items: center;
+  gap: 4px;
+}
+
+.header-dropdown-caret {
+  font-size: 13px;
+}
+
 .theme-toggle,
 .restart-btn {
   display: inline-flex;