diff --git a/backend/app/contracts.py b/backend/app/contracts.py
index a7b4f6f..fa8913c 100644
--- a/backend/app/contracts.py
+++ b/backend/app/contracts.py
@@ -116,6 +116,7 @@ class NoteUpdateRequest(Contract):
     title: str | None = None
     markdown: str | None = None
     tags: list[str] | None = None
+    expected_content_hash: str | None = Field(default=None, pattern=r"^[0-9a-f]{64}$")
 
 
 class NoteMoveRequest(Contract):
diff --git a/backend/app/routes.py b/backend/app/routes.py
index 2cd285d..2fee500 100644
--- a/backend/app/routes.py
+++ b/backend/app/routes.py
@@ -225,7 +225,7 @@ async def open_workspace(request: WorkspaceOpenRequest) -> WorkspaceSnapshot:
 
 @router.get("/workspace/tree", response_model=list[WorkspaceEntry], tags=["Workspace"])
 async def get_workspace_tree() -> list[WorkspaceEntry]:
-    return workspace_service.get_workspace_tree()
+    return await workspace_service.refresh_workspace_tree()
 
 
 @router.post("/workspace/folders", response_model=WorkspaceEntry, tags=["Workspace"])
@@ -286,7 +286,8 @@ async def get_note(note_id: str) -> Note:
 @router.patch("/notes/{note_id}", response_model=Note, tags=["Notes"])
 async def update_note(note_id: str, request: NoteUpdateRequest) -> Note:
     return await note_service.update_note(
-        note_id, title=request.title, markdown=request.markdown, tags=request.tags, defer_vectors=True
+        note_id, title=request.title, markdown=request.markdown, tags=request.tags,
+        expected_content_hash=request.expected_content_hash, defer_vectors=True
     )
 
 
diff --git a/backend/app/services/workspace_service.py b/backend/app/services/workspace_service.py
index 402885d..0046b8d 100644
--- a/backend/app/services/workspace_service.py
+++ b/backend/app/services/workspace_service.py
@@ -105,6 +105,14 @@ def get_workspace_tree() -> list[WorkspaceEntry]:
     return _tree(get_settings().vault_path.resolve(), locations)
 
 
+async def refresh_workspace_tree() -> list[WorkspaceEntry]:
+    """Observe external creates/deletes without waiting for vector inference."""
+    if get_workspace_info().requires_refresh:
+        await _register_workspace_files()
+        index_service.schedule_workspace_rebuild()
+    return get_workspace_tree()
+
+
 async def open_workspace(requested_path: str | None) -> WorkspaceSnapshot:
     """打开只登记文件与全文索引，不让 Embedding 或厂商网络阻塞工作区。"""
 
diff --git a/backend/tests/test_workspace.py b/backend/tests/test_workspace.py
index d32bea3..4794917 100644
--- a/backend/tests/test_workspace.py
+++ b/backend/tests/test_workspace.py
@@ -114,3 +114,34 @@ def test_workspace_openapi_paths_are_published() -> None:
         "/api/workspace/folders/delete",
         "/api/notes/{note_id}/rename",
     } <= paths.keys()
+
+def test_external_files_are_registered_and_removed_without_vector_wait(monkeypatch) -> None:
+    from app.services import index_service
+    scheduled = []
+    monkeypatch.setattr(index_service, 'schedule_workspace_rebuild', lambda: scheduled.append(True))
+    vault = get_settings().vault_path
+    vault.mkdir(parents=True, exist_ok=True)
+    external = vault / 'external.md'
+    external.write_text('# External\n', encoding='utf-8')
+    tree = asyncio.run(get_workspace_tree())
+    assert tree[0].note_id is not None
+    external.rename(vault / 'renamed.md')
+    tree = asyncio.run(get_workspace_tree())
+    assert [item.name for item in tree] == ['renamed.md']
+    (vault / 'renamed.md').unlink()
+    assert asyncio.run(get_workspace_tree()) == []
+    assert len(scheduled) == 3
+
+
+def test_save_rejects_external_content_change() -> None:
+    import hashlib
+    from app.contracts import NoteUpdateRequest
+    from app.routes import update_note
+    original = '# Original\n'
+    note = asyncio.run(create_note(NoteCreateRequest(title='Conflict', markdown=original)))
+    disk = get_settings().vault_path / note.file_path
+    disk.write_text('# External\n', encoding='utf-8')
+    with pytest.raises(ApiError) as error:
+        asyncio.run(update_note(note.note_id, NoteUpdateRequest(markdown='# Editor\n', expected_content_hash=hashlib.sha256(original.encode()).hexdigest())))
+    assert error.value.code == 'NOTE_CONTENT_CONFLICT'
+    assert disk.read_text(encoding='utf-8') == '# External\n'
diff --git a/docs/README.md b/docs/README.md
index 2cb6e38..44877b4 100644
--- a/docs/README.md
+++ b/docs/README.md
@@ -42,6 +42,7 @@
 - [模型上下文管理](development/模型上下文管理.md)
 - [Markdown 渲染检查](development/Markdown渲染检查.md)
 - [警告框与桌面编辑命令开发说明](development/警告框与桌面编辑命令开发说明.md)
+- [标题折叠与样式开发说明](development/标题折叠与样式开发说明.md)
 - [主题组件覆盖检查](development/主题组件覆盖检查.md)
 - [第二阶段补充验收工具](development/第二阶段补充验收工具.md)
 
@@ -92,3 +93,5 @@
 - 问题复盘至少写清原因、后果、解决思路、实际方案和验证结果。
 - `.local-plans/` 只保存个人或阶段性的本地计划，不属于正式团队文档，不应提交到远程仓库。
 - 文档中的“计划实现”和“已经实现”必须明确区分；实现状态以代码、测试和运行时契约为准。
+
+- [Markdown 语法预设与外部文件刷新](development/Markdown语法预设与外部文件刷新.md)
diff --git a/docs/development/Markdown语法预设与外部文件刷新.md b/docs/development/Markdown语法预设与外部文件刷新.md
new file mode 100644
index 0000000..24c63d6
--- /dev/null
+++ b/docs/development/Markdown语法预设与外部文件刷新.md
@@ -0,0 +1,48 @@
+# Markdown 语法预设与外部文件刷新
+
+日期：2026-09-06。
+
+## 1. 设置入口与范围
+
+“设置 → 编辑器 → Markdown 语法预设”管理语法与编辑行为，独立于“标题样式”的字号、字体和字重设置。
+
+支持 ATX/Setext 标题、无序列表标记、有序列表递增、代码围栏、裸链接识别、数学公式、警告框、Mermaid、代码行号、自动换行、缩进和工具栏新建代码块的默认语言。Setext 只作用于 H1/H2。提供扩展、GitHub 和基础三组内置配置，支持最多 20 个命名自定义预设，同名保存替换旧配置。
+
+配置保存在本机 localStorage 的 `markdown-preferences`，读取时校验。静态预览即时应用；写作编辑器在下次打开时应用，避免切换设置重建正在编辑的文档。写作模式保存会统一整篇正文的语法标记，源码模式保留手写语法。关闭扩展后对应内容按普通 Markdown/代码展示。
+
+本次不是完整复制 Typora：未提供上下标、高亮、智能标点、physics 包及导出公式选项。基础配置仍支持现有 GFM 表格等功能。
+
+## 2. 主题与折叠
+
+六个主题共用语义颜色和表单控件。内置浅色、深色、护眼更新为 1.3.0；纸间时光 1.8.0；Ocean Blue 1.5.0；Midnight Purple 2.3.0。社区预览增加语法控件和标题折叠样本。
+
+标题箭头使用统一 CSS 形状，默认隐藏，悬停标题或键盘聚焦按钮时显示；无悬停能力的触摸设备保持可见。用户自定义标题外观独立于主题配色。
+
+## 3. 外部文件刷新与保存保护
+
+Web 当前采用串行后台轮询：前一次完成后间隔两秒，在窗口聚焦时也检查。隐藏页面暂停读取，卸载移除监听。此机制不是原生文件事件监听；第三阶段可由 Tauri 文件事件替代。
+
+`GET /workspace/tree` 检查磁盘新增、删除和重命名，为新文件登记元数据及全文索引，向量任务继续后台执行。前端保留文件夹展开状态，并丢弃过期请求响应。读取失败保留旧树并显示重试入口。
+
+当前打开且未修改的文件检测到外部正文变化后更新编辑器；存在本地编辑时保留缓冲区，停止自动保存并提示冲突。重新加载磁盘版本需要用户确认。`PATCH /notes/{note_id}` 新增可选 `expected_content_hash`（原始正文 UTF-8 SHA-256，64 位小写十六进制），保存前校验，不匹配返回 `NOTE_CONTENT_CONFLICT`，防止覆盖外部修改。
+
+范围限制：现有文件的外部正文修改会刷新当前编辑器，但本轮目录检查不会据此重建其搜索索引；可通过重建索引同步检索内容。
+
+## 4. 验证方法
+
+```powershell
+cd frontend
+npm run test
+npm run build
+cd ..
+backend/.venv/Scripts/python.exe -m pytest backend/tests/test_workspace.py backend/tests/test_workspace_background.py -q -p no:cacheprovider
+```
+
+手工验证：
+
+1. 保存并重新应用命名预设，刷新后确认保留；重新打开笔记，检查 Setext、列表和代码围栏的源码。
+2. 切换六个主题，在社区预览和工作区检查控件、警告框、标题箭头；移出标题后箭头隐藏，Tab 聚焦仍可操作。
+3. 在系统文件管理器新增、重命名、删除 Markdown 文件，保持前端可见，确认树自动更新且目录展开状态保留。
+4. 分别在正文未修改、有未保存编辑时从外部修改同一文件，验证自动加载与冲突保护；拒绝重新加载应保留编辑内容。
+
+本次自动验证覆盖预设持久化、解析选项隔离、写作语法输出、标题折叠、树刷新竞态、外部文件登记及保存冲突。
diff --git a/docs/development/标题折叠与样式开发说明.md b/docs/development/标题折叠与样式开发说明.md
new file mode 100644
index 0000000..ae5945e
--- /dev/null
+++ b/docs/development/标题折叠与样式开发说明.md
@@ -0,0 +1,52 @@
+# 标题折叠与样式开发说明
+
+日期：2026-09-06。范围为工作区写作模式的章节折叠，以及正文标题外观偏好。
+
+## 1. 章节边界与交互
+
+H1–H6 标题旁在悬停时显示统一折叠箭头；键盘聚焦也显示，触摸设备保持可见。章节从标题之后开始，结束于同一容器内下一个同级或更高级标题；末尾没有后续内容的标题不显示按钮。引用等容器中的标题只影响所在容器，不折叠外部正文。
+
+- 工具栏提供“折叠所有章节”和“展开所有章节”。
+- 折叠父章节不会清空子章节的折叠状态。
+- 折叠时若选区在将隐藏的正文中，光标先移到标题。
+- 从大纲、查找或键盘跳到隐藏内容时，展开包含目标的章节，避免隐藏光标。
+- 折叠只影响当前编辑器视图，不修改 Markdown，不触发文档脏状态，也不占用撤销历史。重开文件恢复展开；源码模式与静态预览不进行章节折叠。
+
+实现位于 `headingFolding.ts`：插件状态保存标题位置，通过事务映射跟随文档编辑；删除或改成正文的标题会从状态中清理。Decoration 隐藏完整块，widget 提供可聚焦的折叠按钮。章节范围按标题栈计算，并按不可变文档缓存；隐藏范围合并后遍历节点，避免每个节点重复扫描全部标题。
+
+## 2. 标题样式设置
+
+入口为“设置 → 编辑器 → 标题样式”，主题页“编辑器外观”中也提供同一组件。
+
+- 默认跟随当前主题，不覆盖主题字号、字体与粗细。
+- 启用自定义后，分别调整 H1–H6 字号（12–72 px）和字重（400–800 的五个档位）。
+- 标题字体可跟随正文，或使用系统衬线、无衬线、等宽字体。
+- 面板即时预览，工作区正文和静态 Markdown 预览使用同一偏好。
+- 不影响笔记属性栏的标题、侧栏大纲字号或页面标题，不改写源文件中的标题级别。
+- “恢复跟随主题”清除自定义覆盖；主题页“恢复默认”也重置标题设置。
+
+偏好由 `headingAppearance` store 保存到本机 `editor-heading-appearance`。读取时校验字体枚举、字重与字号范围；应用 CSS 前再次规范化，避免空输入、无效存储或异常大数影响布局。刷新后恢复设置，切换主题保留自定义偏好。用户显式启用的覆盖只作用于 Markdown 标题，优先于主题规则；颜色继续跟随主题。
+
+## 3. 桌面命令预留
+
+既有 `editorCommandService` v1 增加三个可执行 ID：
+
+| 命令 | 行为 |
+| --- | --- |
+| editor.heading.toggle-fold | 切换选区所在章节的折叠状态 |
+| editor.heading.fold-all | 折叠所有有内容的章节 |
+| editor.heading.unfold-all | 展开所有章节 |
+
+均不需要参数，沿用活动文档、模式与冲突检查。原生快捷键仍由第三阶段容器绑定，此处不注册系统级快捷键。
+
+## 4. 验证
+
+```sh
+cd frontend
+npm run test -- src/features/editor/headingFolding.spec.ts src/features/editor/VisualMarkdownEditor.spec.ts src/features/editor/HeadingStyleSettings.spec.ts src/stores/headingAppearance.spec.ts
+npm run build
+```
+
+自动检查覆盖章节边界、嵌套容器、隐藏选区迁移、父子折叠状态、大纲目标展开、序列化保持、设置保存恢复、输入校验和面板恢复默认。
+
+手动检查：打开“功能演示 / 01 Markdown 与大纲”，依次折叠 H2 与 H1，再从大纲跳转；确认隐藏内容重新显示。打开设置调整 H1 字号与 H2 粗细，返回笔记检查外观，刷新后检查偏好仍在；关闭自定义后依次切换六个主题核对主题原有样式。
diff --git a/frontend/README.md b/frontend/README.md
index a5e5d3a..ddbed52 100644
--- a/frontend/README.md
+++ b/frontend/README.md
@@ -41,6 +41,8 @@ pnpm dev
 
 编辑器使用 Milkdown/Crepe 与 CodeMirror 6；Markdown 展示使用 marked、DOMPurify 和 Shiki。Provider logo 位于 `src/assets/providers`，授权与来源说明随目录保存。
 
+写作模式支持按标题折叠章节及全部展开/折叠；“设置 → 编辑器 → 标题样式”可按 H1–H6 设置字号、粗细与标题字体。设置本地保存，不改写 Markdown；详见 [标题折叠与样式开发说明](../docs/development/标题折叠与样式开发说明.md)。
+
 工作区和静态预览支持 GitHub alerts / Obsidian callout 的类型、别名、标题、嵌套与折叠。桌面快捷键使用预留的 v1 编辑命令边界，尚未接入 Tauri 原生快捷键与元数据转换处理器；见 [警告框与桌面编辑命令开发说明](../docs/development/警告框与桌面编辑命令开发说明.md)。
 
 语言设置会即时更新主导航、页面标题和各功能页面，并同步更新文档与编辑器的 `lang`。拼写检查使用浏览器或桌面 WebView 提供的本地词典，开关会即时作用于可视化 Markdown、源码编辑器以及普通文本输入；JSON、密码等结构化或敏感输入保持关闭。
@@ -92,3 +94,5 @@ Mermaid 大图打开时适配窗口，支持平滑滚轮缩放和鼠标位置补
 ## 构建体积检查
 
 执行 `pnpm build` 后运行 `pnpm build:report`，查看入口静态 JS 依赖与大块清单。分组策略、统计口径及保留的大资源见 [前端构建分块优化开发说明](../docs/development/前端构建分块优化开发说明.md)。
+
+Markdown 语法预设、主题适配和外部文件刷新规则见 [开发说明](../docs/development/Markdown语法预设与外部文件刷新.md)。
diff --git a/frontend/src/assets/themes/paper-moments.theme b/frontend/src/assets/themes/paper-moments.theme
index ea37ee9..667b04f 100644
--- a/frontend/src/assets/themes/paper-moments.theme
+++ b/frontend/src/assets/themes/paper-moments.theme
@@ -1,6 +1,6 @@
 theme_id: paper-moments
 name: 纸间时光 · Paper Moments
-version: 1.7.0
+version: 1.8.0
 author: NotesAgent
 description: 奶油纸张、手帐虚线与粉蓝胶带，把每天的灵感好好收藏。
 min_app_version: 0.2.0
diff --git a/frontend/src/components/common/AppShell.vue b/frontend/src/components/common/AppShell.vue
index 26cc83f..2d792ee 100644
--- a/frontend/src/components/common/AppShell.vue
+++ b/frontend/src/components/common/AppShell.vue
@@ -12,6 +12,8 @@ import TitleBar from './TitleBar.vue'
 import CommandPalette from './CommandPalette.vue'
 import { getIndexStatus } from '@/services/indexService'
 import { navigateToCitation } from '@/composables/useCitationNavigation'
+import { useWorkspaceRefresh } from '@/composables/useWorkspaceRefresh'
+useWorkspaceRefresh()
 
 defineProps<{
   showSecondarySidebar?: boolean
diff --git a/frontend/src/components/common/MarkdownContent.vue b/frontend/src/components/common/MarkdownContent.vue
index ebb1576..0fdf620 100644
--- a/frontend/src/components/common/MarkdownContent.vue
+++ b/frontend/src/components/common/MarkdownContent.vue
@@ -3,6 +3,10 @@ import DiagramInteractions from './DiagramInteractions.vue'
 import { computed, ref, watch } from 'vue'
 import { renderMarkdown } from '@/utils/markdown'
 import { useThemeStore } from '@/stores/theme'
+import { useHeadingAppearanceStore } from '@/stores/headingAppearance'
+const headingAppearance = useHeadingAppearanceStore()
+import { useMarkdownPreferencesStore } from '@/stores/markdownPreferences'
+const markdownPreferences = useMarkdownPreferencesStore()
 
 const props = defineProps<{ source: string }>()
 const themeStore = useThemeStore()
@@ -12,15 +16,15 @@ let renderVersion = 0
 const diagramTheme = computed<'light' | 'dark'>(() => (themeStore.isDark ? 'dark' : 'light'))
 
 // 主题切换需要重渲染：Mermaid SVG 的配色在渲染时烘焙，无法靠 CSS 变量事后调整。
-watch([() => props.source, diagramTheme, () => themeStore.currentThemeId], async ([source, theme]) => {
+watch([() => props.source, diagramTheme, () => themeStore.currentThemeId, () => JSON.stringify(markdownPreferences.normalized)], async ([source, theme]) => {
   const version = ++renderVersion
-  const result = await renderMarkdown(source, { theme })
+  const result = await renderMarkdown(source, { theme, preferences: markdownPreferences.normalized })
   if (version === renderVersion) html.value = result
 }, { immediate: true, flush: 'post' })
 </script>
 
 <template>
-  <DiagramInteractions><div class="markdown-content" v-html="html" /></DiagramInteractions>
+  <DiagramInteractions :data-heading-style="headingAppearance.preferences.custom ? 'custom' : undefined" :style="headingAppearance.cssVariables"><div class="markdown-content" v-html="html" /></DiagramInteractions>
 </template>
 
 <style>
diff --git a/frontend/src/composables/useWorkspaceRefresh.ts b/frontend/src/composables/useWorkspaceRefresh.ts
new file mode 100644
index 0000000..f5a8502
--- /dev/null
+++ b/frontend/src/composables/useWorkspaceRefresh.ts
@@ -0,0 +1,40 @@
+import { onMounted, onUnmounted } from 'vue'
+import { useWorkspaceStore } from '@/stores/workspace'
+import { useEditorStore } from '@/stores/editor'
+
+/** Web fallback until the desktop host supplies filesystem events. No overlapping polls. */
+export function useWorkspaceRefresh() {
+  const workspace = useWorkspaceStore()
+  const editor = useEditorStore()
+  let stopped = false
+  let running = false
+  let timer: ReturnType<typeof setTimeout> | undefined
+  async function refresh() {
+    if (running || stopped) return
+    clearTimeout(timer)
+    running = true
+    try {
+      if (document.visibilityState !== 'hidden' && workspace.hasVault) {
+        await workspace.refreshFileTree()
+        if (!stopped) {
+          if (editor.currentFilePath && editor.currentFilePath === workspace.activeFilePath && !workspace.activeFile) editor.setExternalChanged()
+          else await editor.checkExternalFile()
+        }
+      }
+    } catch { /* Keep the existing tree; the store exposes the error and retries. */ }
+    finally {
+      running = false
+      if (!stopped) timer = setTimeout(refresh, 2000)
+    }
+  }
+  onMounted(() => {
+    window.addEventListener('focus', refresh)
+    document.addEventListener('visibilitychange', refresh)
+    void refresh()
+  })
+  onUnmounted(() => {
+    stopped = true; clearTimeout(timer)
+    window.removeEventListener('focus', refresh)
+    document.removeEventListener('visibilitychange', refresh)
+  })
+}
diff --git a/frontend/src/features/editor/EditorHeader.vue b/frontend/src/features/editor/EditorHeader.vue
index dd0dda9..a95818f 100644
--- a/frontend/src/features/editor/EditorHeader.vue
+++ b/frontend/src/features/editor/EditorHeader.vue
@@ -1,11 +1,21 @@
 <script setup lang="ts">
 import { useEditorStore } from '@/stores/editor'
 import { useWorkspaceStore } from '@/stores/workspace'
-import { computed } from 'vue'
+import { computed, ref } from 'vue'
+import ActionDialog from '@/components/common/ActionDialog.vue'
+import { useActionDialog } from '@/composables/useActionDialog'
 import { t } from '@/i18n'
 
 const editorStore = useEditorStore()
 const workspaceStore = useWorkspaceStore()
+const { actionDialog, resolveAction, askConfirm } = useActionDialog()
+const reloadError = ref('')
+async function reload() {
+  const path = editorStore.currentFilePath, snapshot = editorStore.content
+  if (!(await askConfirm(t('重新加载会丢弃当前未保存内容。请先复制需要保留的文字。继续吗？', 'Reload discards unsaved edits. Copy any text you need to keep first. Continue?')))) return
+  if (path !== editorStore.currentFilePath || snapshot !== editorStore.content) return
+  try { await editorStore.reloadExternalFile(); reloadError.value = '' } catch (error) { reloadError.value = error instanceof Error ? error.message : '重新加载失败' }
+}
 
 const statusText = computed<Record<string, string>>(() => ({
   idle: t('空闲', 'Idle'), dirty: t('未保存', 'Unsaved'), saving: t('保存中…', 'Saving…'), saved: t('已保存', 'Saved'), save_failed: t('保存失败', 'Save failed'),
@@ -15,14 +25,17 @@ const statusText = computed<Record<string, string>>(() => ({
 
 <template>
   <header class="editor-header">
+    <ActionDialog v-if="actionDialog" v-bind="actionDialog" @resolve="resolveAction" />
     <div class="file-identity"><strong>{{ workspaceStore.activeFile?.name ?? t('未命名笔记', 'Untitled note') }}</strong><small>{{ workspaceStore.activeFilePath }}</small></div>
     <div class="editor-actions">
       <span class="save-status" :class="editorStore.saveStatus">{{ statusText[editorStore.saveStatus] }}</span>
+      <button v-if="['conflict', 'external_changed'].includes(editorStore.saveStatus)" class="button-secondary" @click="reload">{{ t('重新加载外部版本', 'Reload external version') }}</button>
+      <span v-if="reloadError" class="save-status conflict" role="alert">{{ reloadError }}</span>
       <div class="mode-switch" :aria-label="t('编辑模式', 'Editor mode')">
         <button type="button" :class="{ active: editorStore.mode === 'wysiwyg' }" @click="editorStore.setMode('wysiwyg')">{{ t('写作', 'Writing') }}</button>
         <button type="button" :class="{ active: editorStore.mode === 'source' }" @click="editorStore.setMode('source')">{{ t('源码', 'Source') }}</button>
       </div>
-      <button type="button" class="save-button" :disabled="editorStore.saveStatus === 'saving'" @click="editorStore.save">{{ t('保存', 'Save') }}</button>
+      <button type="button" class="save-button" :disabled="['saving','conflict','external_changed'].includes(editorStore.saveStatus)" @click="editorStore.save">{{ t('保存', 'Save') }}</button>
     </div>
   </header>
 </template>
diff --git a/frontend/src/features/editor/EditorPane.vue b/frontend/src/features/editor/EditorPane.vue
index 5232145..da67c2f 100644
--- a/frontend/src/features/editor/EditorPane.vue
+++ b/frontend/src/features/editor/EditorPane.vue
@@ -24,7 +24,7 @@ function updateContent(event: Event) {
 </script>
 
 <template>
-  <VisualMarkdownEditor v-if="editorStore.mode === 'wysiwyg'" :key="`${editorStore.currentFilePath ?? 'empty'}:${themeStore.resolvedCodeBlockTheme}:${settingsStore.language}`"
+  <VisualMarkdownEditor v-if="editorStore.mode === 'wysiwyg'" :key="`${editorStore.currentFilePath ?? 'empty'}:${editorStore.contentRevision}:${themeStore.resolvedCodeBlockTheme}:${settingsStore.language}`"
     :initial-content="editorStore.content" />
   <textarea v-else ref="sourceEditor" class="editor-pane source" :value="editorStore.content" :spellcheck="settingsStore.spellCheck"
     :lang="settingsStore.language" :aria-label="settingsStore.language === 'en' ? 'Markdown source editor' : 'Markdown 源码编辑器'" @input="updateContent" />
diff --git a/frontend/src/features/editor/HeadingStyleSettings.spec.ts b/frontend/src/features/editor/HeadingStyleSettings.spec.ts
new file mode 100644
index 0000000..dedd955
--- /dev/null
+++ b/frontend/src/features/editor/HeadingStyleSettings.spec.ts
@@ -0,0 +1,20 @@
+// @vitest-environment happy-dom
+import { expect, it } from 'vitest'
+import { mount } from '@vue/test-utils'
+import { createPinia } from 'pinia'
+import HeadingStyleSettings from './HeadingStyleSettings.vue'
+it('previews individual heading settings and restores theme inheritance', async () => {
+  localStorage.clear()
+  const wrapper = mount(HeadingStyleSettings, { global: { plugins: [createPinia()] } })
+  try {
+    expect(wrapper.get('input[aria-label="H1 字号"]').attributes('disabled')).toBeDefined()
+    await wrapper.get('input[type="checkbox"]').setValue(true)
+    await wrapper.get('input[aria-label="H1 字号"]').setValue(42)
+    await wrapper.get('select[aria-label="H1 粗细"]').setValue('400')
+    expect(wrapper.get('.heading-style-preview').attributes('style')).toContain('--heading-1-size: 42px')
+    expect(wrapper.get('.heading-style-preview').attributes('style')).toContain('--heading-1-weight: 400')
+    await wrapper.get('button').trigger('click')
+    expect(wrapper.get('.heading-style-preview').attributes('data-heading-style')).toBeUndefined()
+    expect(wrapper.get('.heading-style-preview').attributes('style') ?? '').not.toContain('--heading-1-size')
+  } finally { wrapper.unmount() }
+})
diff --git a/frontend/src/features/editor/HeadingStyleSettings.vue b/frontend/src/features/editor/HeadingStyleSettings.vue
new file mode 100644
index 0000000..675b27e
--- /dev/null
+++ b/frontend/src/features/editor/HeadingStyleSettings.vue
@@ -0,0 +1,37 @@
+<script setup lang="ts">
+import { useHeadingAppearanceStore } from '@/stores/headingAppearance'
+import { t } from '@/i18n'
+const appearance = useHeadingAppearanceStore()
+</script>
+
+<template>
+  <details class="ui-disclosure heading-style-settings">
+    <summary>{{ t('标题样式', 'Heading styles') }}</summary>
+    <div class="heading-settings-body">
+      <label><input v-model="appearance.preferences.custom" type="checkbox" /> {{ t('自定义标题样式', 'Customize heading styles') }}</label>
+      <p class="subtle">{{ t('关闭时跟随主题。设置作用于正文 H1–H6，不改写 Markdown，也不改变笔记属性标题。', 'Disable to follow the theme. Applies to document H1–H6 without rewriting Markdown or the metadata title.') }}</p>
+      <label>{{ t('标题字体', 'Heading font') }}
+        <select v-model="appearance.preferences.family" class="select" :disabled="!appearance.preferences.custom">
+          <option value="inherit">{{ t('跟随正文', 'Follow body') }}</option><option value="serif">{{ t('衬线字体', 'Serif') }}</option><option value="sans-serif">{{ t('无衬线字体', 'Sans serif') }}</option><option value="monospace">{{ t('等宽字体', 'Monospace') }}</option>
+        </select>
+      </label>
+      <div v-for="(level, index) in appearance.preferences.levels" :key="index" class="heading-setting-row">
+        <strong>H{{ index + 1 }}</strong>
+        <label>{{ t('字号 px', 'Size px') }}<input v-model.number="level.size" class="input" type="number" min="12" max="72" :disabled="!appearance.preferences.custom" :aria-label="`H${index + 1} ${t('字号', 'size')}`" /></label>
+        <label>{{ t('粗细', 'Weight') }}<select v-model.number="level.weight" class="select" :disabled="!appearance.preferences.custom" :aria-label="`H${index + 1} ${t('粗细', 'weight')}`"><option :value="400">{{ t('常规', 'Regular') }}</option><option :value="500">Medium</option><option :value="600">Semibold</option><option :value="700">{{ t('加粗', 'Bold') }}</option><option :value="800">Extra bold</option></select></label>
+      </div>
+      <button class="button-secondary" type="button" @click="appearance.reset">{{ t('恢复跟随主题', 'Restore theme defaults') }}</button>
+      <div class="heading-style-preview" :data-heading-style="appearance.preferences.custom ? 'custom' : undefined" :style="appearance.cssVariables">
+        <div class="markdown-content"><component :is="`h${index + 1}`" v-for="(_, index) in appearance.preferences.levels" :key="index">H{{ index + 1 }} {{ t('标题预览', 'Heading preview') }}</component></div>
+      </div>
+    </div>
+  </details>
+</template>
+
+<style scoped>
+.heading-settings-body { display: grid; gap: 14px; padding: 16px; }
+.heading-setting-row { display: grid; grid-template-columns: 40px minmax(0, 1fr) minmax(0, 1fr); gap: 12px; align-items: end; }
+.heading-setting-row label { display: grid; gap: 6px; min-width: 0; }
+.heading-setting-row strong { align-self: center; }
+.heading-style-preview { border: 1px solid var(--color-border-default); border-radius: var(--radius-md); padding: 16px; overflow-wrap: anywhere; background: var(--color-surface-primary); color: var(--color-text-primary); }
+</style>
diff --git a/frontend/src/features/editor/MarkdownPreferenceSettings.vue b/frontend/src/features/editor/MarkdownPreferenceSettings.vue
new file mode 100644
index 0000000..bdbdff3
--- /dev/null
+++ b/frontend/src/features/editor/MarkdownPreferenceSettings.vue
@@ -0,0 +1,45 @@
+<script setup lang="ts">
+import { ref } from 'vue'
+import { useMarkdownPreferencesStore, markdownPresets } from '@/stores/markdownPreferences'
+import { t } from '@/i18n'
+const store = useMarkdownPreferencesStore()
+const name = ref('')
+const error = ref('')
+function save() { error.value = store.savePreset(name.value) ? '' : t('请输入名称，最多保存 20 个预设。', 'Enter a name; up to 20 presets.'); if (!error.value) name.value = '' }
+</script>
+<template>
+  <section class="markdown-preferences surface-nested">
+    <h3>{{ t('Markdown 语法与编辑预设', 'Markdown syntax and editing presets') }}</h3>
+    <p class="subtle">{{ t('语法和代码设置在下次打开写作编辑器时应用；不批量改写已有笔记。静态预览即时更新。', 'Syntax and code settings apply when the visual editor next opens; existing notes are not rewritten in bulk. Static previews update immediately.') }}</p>
+    <div class="inline-actions"><button class="button-secondary" @click="store.apply(markdownPresets.extended)">{{ t('扩展 Markdown', 'Extended Markdown') }}</button><button class="button-secondary" @click="store.apply(markdownPresets.github)">GitHub</button><button class="button-secondary" @click="store.apply(markdownPresets.plain)">{{ t('基础 Markdown', 'Basic Markdown') }}</button></div>
+    <div class="form-grid">
+      <label>{{ t('标题语法', 'Heading syntax') }}<select v-model="store.preferences.heading" class="select"><option value="atx">ATX (#)</option><option value="setext">Setext (=== / ---)</option></select></label>
+      <label>{{ t('无序列表', 'Bullet list') }}<select v-model="store.preferences.bullet" class="select"><option>-</option><option>*</option><option>+</option></select></label>
+      <label>{{ t('有序列表', 'Ordered list') }}<select v-model="store.preferences.incrementList" class="select"><option :value="true">1. 2. 3.</option><option :value="false">1. 1. 1.</option></select></label>
+      <label>{{ t('代码围栏', 'Code fence') }}<select v-model="store.preferences.fence" class="select"><option value="`">```</option><option value="~">~~~</option></select></label>
+    </div>
+    <p class="subtle">{{ t('Setext 适用于 H1/H2，H3–H6 仍使用 #。写作模式保存时会规范化整篇正文的标记；源码模式保留手写语法。', 'Setext applies to H1/H2; H3–H6 use #. Visual-mode saves normalize document markers; source mode preserves handwritten syntax.') }}</p>
+    <div class="markdown-switches">
+      <label><input v-model="store.preferences.autoLinks" type="checkbox" />{{ t('自动识别裸链接', 'Recognize bare URLs') }}</label>
+      <label><input v-model="store.preferences.math" type="checkbox" />{{ t('数学公式', 'Math') }}</label>
+      <label><input v-model="store.preferences.callouts" type="checkbox" />{{ t('警告框与提示框', 'Alerts and callouts') }}</label>
+      <label><input v-model="store.preferences.diagrams" type="checkbox" />Mermaid</label>
+      <label><input v-model="store.preferences.lineNumbers" type="checkbox" />{{ t('代码行号', 'Code line numbers') }}</label>
+      <label><input v-model="store.preferences.wrapCode" type="checkbox" />{{ t('代码自动换行', 'Wrap code') }}</label>
+    </div>
+    <div class="form-grid">
+      <label>{{ t('代码缩进', 'Code indent') }}<select v-model.number="store.preferences.indent" class="select"><option :value="2">2</option><option :value="4">4</option><option :value="8">8</option></select></label>
+      <label>{{ t('新建代码块默认语言', 'Default language for new code blocks') }}<input v-model="store.preferences.defaultLanguage" class="input" maxlength="40" placeholder="python" /></label>
+    </div>
+    <form class="inline-actions" @submit.prevent="save"><input v-model="name" class="input" maxlength="40" :aria-label="t('预设名称', 'Preset name')" :placeholder="t('我的预设名称', 'My preset name')" /><button class="button-primary">{{ t('保存为预设', 'Save preset') }}</button></form>
+    <p v-if="error" class="error-banner" role="alert">{{ error }}</p>
+    <div v-for="(preset, index) in store.customPresets" :key="preset.name" class="inline-actions"><strong>{{ preset.name }}</strong><button class="button-secondary" @click="store.apply(preset.preferences)">{{ t('应用', 'Apply') }}</button><button class="button-danger" @click="store.customPresets.splice(index, 1)">{{ t('删除', 'Delete') }}</button></div>
+  </section>
+</template>
+<style scoped>
+.markdown-preferences { display: grid; gap: 16px; padding: 16px; margin-block: 16px; }
+.markdown-preferences .form-grid > label { display: grid; gap: 6px; min-width: 0; }
+.markdown-switches { display: grid; grid-template-columns: repeat(auto-fit,minmax(190px,1fr)); gap: 12px; }
+.markdown-switches label { display: flex; align-items: center; gap: 8px; }
+.inline-actions { flex-wrap: wrap; }
+</style>
diff --git a/frontend/src/features/editor/VisualMarkdownEditor.spec.ts b/frontend/src/features/editor/VisualMarkdownEditor.spec.ts
index 086359b..795c90d 100644
--- a/frontend/src/features/editor/VisualMarkdownEditor.spec.ts
+++ b/frontend/src/features/editor/VisualMarkdownEditor.spec.ts
@@ -15,6 +15,8 @@ import { EditorView as CodeMirror } from '@codemirror/view'
 import { renderMarkdown } from '@/utils/markdown'
 import { useEditorStore } from '@/stores/editor'
 import { executeEditorCommand } from '@/services/editorCommandService'
+import { headingFoldKey } from './headingFolding'
+import { useMarkdownPreferencesStore } from '@/stores/markdownPreferences'
 
 type EditorComponent = { getEditor: () => Editor | undefined }
 
@@ -53,6 +55,47 @@ afterEach(() => {
 })
 
 describe('VisualMarkdownEditor formatting toolbars', () => {
+  it('applies syntax and renderer preferences when opening the visual editor', async () => {
+    const preferences = useMarkdownPreferencesStore()
+    preferences.preferences.heading = 'setext'
+    preferences.preferences.bullet = '+'
+    preferences.preferences.fence = '~'
+    preferences.preferences.callouts = false
+    preferences.preferences.math = false
+    preferences.preferences.autoLinks = false
+    const wrapper = mount(VisualMarkdownEditor, { props: { initialContent: '# Heading\n\n- first\n- second\n\n> [!NOTE]\n> text\n\nhttps://example.com\n\n```text\ncode\n```' }, attachTo: document.body })
+    mounted.push(wrapper)
+    const editor = await waitForEditor(wrapper)
+    const result = editor.action(getMarkdown())
+    expect(result).toContain('Heading\n===')
+    expect(result).toContain('+ first')
+    expect(result).toContain('~~~text')
+    expect(wrapper.find('.markdown-callout').exists()).toBe(false)
+    expect(wrapper.find('.ProseMirror a').exists()).toBe(false)
+  })
+  it('folds heading sections, retains nested state and opens hidden outline targets', async () => {
+    const source = '# A\n\nbody\n\n## B\n\nchild\n\n# C\n\nvisible'
+    const wrapper = mount(VisualMarkdownEditor, { props: { initialContent: source }, attachTo: document.body })
+    mounted.push(wrapper)
+    const editor = await waitForEditor(wrapper)
+    await wrapper.get('.heading-fold-toggle[aria-label="折叠 H2 B"]').trigger('click')
+    await wrapper.get('.heading-fold-toggle[aria-label="折叠 H1 A"]').trigger('click')
+    expect(wrapper.findAll('.heading-fold-hidden').length).toBeGreaterThan(1)
+    await wrapper.get('.heading-fold-toggle[aria-label="展开 H1 A"]').trigger('click')
+    expect(wrapper.get('.heading-fold-toggle[aria-label="展开 H2 B"]').attributes('aria-expanded')).toBe('false')
+    editor.action(ctx => {
+      const view = ctx.get(editorViewCtx)
+      let position = 0
+      view.state.doc.descendants((node, pos) => { if (node.isText && node.text === 'child') position = pos })
+      view.dispatch(view.state.tr.setSelection(TextSelection.create(view.state.doc, position)))
+      expect(headingFoldKey.getState(view.state)?.size).toBe(0)
+    })
+    expect(wrapper.find('.heading-fold-hidden').exists()).toBe(false)
+    expect(editor.action(getMarkdown()).trim()).toBe(source)
+    await wrapper.get('button[aria-label="折叠所有章节"]').trigger('click')
+    await wrapper.get('button[aria-label="展开所有章节"]').trigger('click')
+    expect(wrapper.find('.heading-fold-hidden').exists()).toBe(false)
+  })
   it('renders and folds callouts without losing portable Markdown on serialization', async () => {
     const source = '> [!WARNING]- 注意\n>\n> **正文**\n>\n> > [!TIP] 内层\n> > 内容'
     const wrapper = mount(VisualMarkdownEditor, { props: { initialContent: source }, attachTo: document.body })
diff --git a/frontend/src/features/editor/VisualMarkdownEditor.vue b/frontend/src/features/editor/VisualMarkdownEditor.vue
index bbaf9be..4a06067 100644
--- a/frontend/src/features/editor/VisualMarkdownEditor.vue
+++ b/frontend/src/features/editor/VisualMarkdownEditor.vue
@@ -8,7 +8,9 @@ import { Link } from '@element-plus/icons-vue'
 import { Crepe } from '@milkdown/crepe'
 import { codeBlockConfig } from '@milkdown/kit/component/code-block'
 import { basicSetup } from 'codemirror'
-import { keymap } from '@codemirror/view'
+import { keymap, EditorView as CodeEditorView } from '@codemirror/view'
+import { indentUnit } from '@codemirror/language'
+import { EditorState as CodeEditorState } from '@codemirror/state'
 import { indentWithTab } from '@codemirror/commands'
 import { shikiEditorTheme, shikiLanguages, renderCodeLanguage } from './shikiCodeMirror'
 import './language-icons.css'
@@ -16,7 +18,7 @@ import { installLanguagePickerPopover } from './languagePickerPopover'
 import { installCodeBlockLabels } from './codeBlockLabels'
 import { createMermaidPreview } from './mermaidPreview'
 import { splitNoteMetadata, updateMetadataTags } from './noteMetadata'
-import { getMarkdown } from '@milkdown/kit/utils'
+import { getMarkdown, $remark } from '@milkdown/kit/utils'
 import {
   createCodeBlockCommand,
   toggleEmphasisCommand,
@@ -28,7 +30,7 @@ import {
   wrapInHeadingCommand,
   wrapInOrderedListCommand,
 } from '@milkdown/kit/preset/commonmark'
-import { commandsCtx, editorViewCtx, parserCtx } from '@milkdown/kit/core'
+import { commandsCtx, editorViewCtx, parserCtx, remarkStringifyOptionsCtx } from '@milkdown/kit/core'
 import { Slice } from '@milkdown/kit/prose/model'
 import { registerEditorCommands, type CommandHandler, type EditorCommandId } from '@/services/editorCommandService'
 import { TextSelection } from '@milkdown/kit/prose/state'
@@ -41,11 +43,16 @@ import { applyMarkdownFontSize, fontSizeMarkdownPlugin } from './fontSizeMarkdow
 import { inlineCodeInputPlugin } from './inlineCodeInput'
 import { calloutPlugin, configureCalloutSerialization } from './calloutPlugin'
 import { calloutTypes } from '@/utils/callouts'
+import { headingFoldingPlugin, headingFoldTransaction } from './headingFolding'
+import { useHeadingAppearanceStore } from '@/stores/headingAppearance'
+import { useMarkdownPreferencesStore } from '@/stores/markdownPreferences'
 import { t } from '@/i18n'
 import '@milkdown/crepe/theme/common/style.css'
 import '@milkdown/crepe/theme/frame.css'
 
 const props = defineProps<{ initialContent: string }>()
+const headingAppearance = useHeadingAppearanceStore()
+const markdownPreferences = { ...useMarkdownPreferencesStore().normalized }
 const metadata = ref(splitNoteMetadata(props.initialContent))
 const tagDraft = ref('')
 function setTags(tags: string[]) {
@@ -93,8 +100,14 @@ function insertCallout(event: Event) {
 function installCommands() {
   const targetPath = editorStore.currentFilePath
   const handlers: Partial<Record<EditorCommandId, CommandHandler>> = {}
+  for (const [id, action] of [['editor.heading.toggle-fold', 'toggle'], ['editor.heading.fold-all', 'all'], ['editor.heading.unfold-all', 'none']] as const) {
+    handlers[id] = () => { foldHeadings(action); return { ok: true } }
+  }
   const toolbar: ToolbarCommand[] = ['bold', 'italic', 'ordered-list', 'bullet-list', 'inline-code', 'code-block', 'inline-math', 'math-block']
-  for (const command of toolbar) handlers[`editor.${command}`] = () => { runCommand(command); return { ok: true } }
+  for (const command of toolbar) {
+    if (!markdownPreferences.math && command.includes('math')) continue
+    handlers[`editor.${command}`] = () => { runCommand(command); return { ok: true } }
+  }
   handlers['editor.paragraph'] = () => { crepe!.editor.action(callCommand(turnIntoTextCommand.key)); return { ok: true } }
   handlers['editor.heading'] = params => {
     if (!Number.isInteger(params) || Number(params) < 1 || Number(params) > 6) return { ok: false, reason: 'invalid-params' }
@@ -113,6 +126,7 @@ function installCommands() {
     return { ok: true }
   }
   handlers['editor.callout'] = params => {
+    if (!markdownPreferences.callouts) return { ok: false, reason: 'unsupported' }
     if (!params || typeof params !== 'object') return { ok: false, reason: 'invalid-params' }
     const { type, title = '', body = '', fold = '' } = params as Record<string, unknown>
     if (typeof type !== 'string' || !/^[\w-]{1,64}$/.test(type) || typeof title !== 'string' || /[\r\n]/.test(title)
@@ -126,6 +140,14 @@ function installCommands() {
     handlers,
   })
 }
+
+function foldHeadings(action: 'toggle' | 'all' | 'none') {
+  crepe?.editor.action(ctx => {
+    const view = ctx.get(editorViewCtx)
+    const tr = headingFoldTransaction(view.state, action)
+    if (tr) view.dispatch(tr)
+  })
+}
 const diagramPreviews = new Map<string, { source: string; apply: (value: HTMLElement) => void }>()
 function renderDiagram(source: string, apply: (value: HTMLElement) => void) {
   for (const [id, entry] of diagramPreviews) {
@@ -173,7 +195,7 @@ function runCommand(command: ToolbarCommand) {
     'ordered-list': callCommand(wrapInOrderedListCommand.key),
     'bullet-list': callCommand(wrapInBulletListCommand.key),
     'inline-code': callCommand(toggleInlineCodeCommand.key),
-    'code-block': callCommand(createCodeBlockCommand.key, ''),
+    'code-block': callCommand(createCodeBlockCommand.key, markdownPreferences.defaultLanguage),
     'inline-math': callCommand('ToggleLatex'),
     'math-block': callCommand(createCodeBlockCommand.key, 'LaTeX'),
   }
@@ -240,7 +262,7 @@ onMounted(async () => {
   crepe = new Crepe({
     root: editorRoot.value,
     defaultValue: metadata.value?.body ?? props.initialContent,
-    features: { [Crepe.Feature.TopBar]: false },
+    features: { [Crepe.Feature.TopBar]: false, [Crepe.Feature.Latex]: markdownPreferences.math },
     featureConfigs: {
       [Crepe.Feature.Placeholder]: { text: t('开始记录你的想法…', 'Start writing your thoughts…') },
       [Crepe.Feature.CodeMirror]: {
@@ -304,14 +326,35 @@ onMounted(async () => {
     languages: shikiLanguages(themeStore.resolvedCodeBlockTheme),
     renderLanguage: renderCodeLanguage,
     renderPreview: (language, content, applyPreview) => language.trim().toLowerCase() === 'mermaid'
-      ? renderDiagram(content, applyPreview)
+      ? markdownPreferences.diagrams ? renderDiagram(content, applyPreview) : null
       : config.renderPreview(language, content, applyPreview),
-    extensions: [basicSetup, keymap.of([indentWithTab]), shikiEditorTheme(themeStore.resolvedCodeBlockTheme)],
+    extensions: [basicSetup, keymap.of([indentWithTab]), shikiEditorTheme(themeStore.resolvedCodeBlockTheme),
+      indentUnit.of(' '.repeat(markdownPreferences.indent)), CodeEditorState.tabSize.of(markdownPreferences.indent),
+      ...(markdownPreferences.wrapCode ? [CodeEditorView.lineWrapping] : [])],
   })))
+  crepe.editor.config(ctx => ctx.update(remarkStringifyOptionsCtx, options => ({
+    ...options, setext: markdownPreferences.heading === 'setext', bullet: markdownPreferences.bullet,
+    incrementListMarker: markdownPreferences.incrementList, fence: markdownPreferences.fence,
+  })))
+  if (!markdownPreferences.autoLinks) crepe.editor.use($remark('disable-bare-autolinks', () => () => (tree, file) => {
+    type Ast = { type: string; value?: string; url?: string; children?: Ast[]; position?: { start: { offset?: number }; end: { offset?: number } } }
+    const source = String(file.value)
+    const walk = (node: Ast) => {
+      if (node.type === 'link' && node.position) {
+        const raw = source.slice(node.position.start.offset, node.position.end.offset)
+        if (/^(?:https?:\/\/|www\.)\S+$/.test(raw)) {
+          node.type = 'text'; node.value = raw; delete node.children; delete node.url
+        }
+      }
+      node.children?.forEach(walk)
+    }
+    walk(tree as Ast)
+  }))
   crepe.editor.use(fontSizeMarkdownPlugin)
   crepe.editor.use(inlineCodeInputPlugin)
-  crepe.editor.use(calloutPlugin)
-  crepe.editor.config(configureCalloutSerialization)
+  if (markdownPreferences.callouts) crepe.editor.use(calloutPlugin)
+  crepe.editor.use(headingFoldingPlugin)
+  if (markdownPreferences.callouts) crepe.editor.config(configureCalloutSerialization)
   crepe.on((listener) => {
     listener.markdownUpdated((_ctx, markdown, previousMarkdown) => {
       // 忽略编辑器初始化/回显事件，防止无内容变化时触发自动保存循环。
@@ -350,9 +393,11 @@ defineExpose({ getEditor: () => crepe?.editor })
 </script>
 
 <template>
-  <DiagramInteractions class="visual-editor">
+  <DiagramInteractions class="visual-editor" :class="{ 'hide-code-line-numbers': !markdownPreferences.lineNumbers }" :data-heading-style="headingAppearance.preferences.custom ? 'custom' : undefined" :style="headingAppearance.cssVariables">
     <ActionDialog v-if="actionDialog" v-bind="actionDialog" @resolve="resolveAction" />
     <div class="markdown-toolbar" role="toolbar" :aria-label="t('Markdown 格式工具栏', 'Markdown formatting toolbar')">
+      <button type="button" :title="t('折叠所有章节', 'Fold all sections')" :aria-label="t('折叠所有章节', 'Fold all sections')" @click="foldHeadings('all')">▸</button>
+      <button type="button" :title="t('展开所有章节', 'Unfold all sections')" :aria-label="t('展开所有章节', 'Unfold all sections')" @click="foldHeadings('none')">▾</button>
       <label class="toolbar-select heading-select" :title="t('设置标题级别', 'Set heading level')">
         <span class="format-glyph heading-glyph">H</span>
         <select :aria-label="t('标题级别', 'Heading level')" @change="applyHeading">
@@ -383,11 +428,11 @@ defineExpose({ getEditor: () => crepe?.editor })
       <span class="toolbar-divider" />
       <button type="button" :title="t('行内代码', 'Inline code')" :aria-label="t('行内代码', 'Inline code')" @pointerdown.prevent="runCommand('inline-code')"><code class="code-glyph">&lt;/&gt;</code></button>
       <button type="button" :title="t('代码块', 'Code block')" :aria-label="t('代码块', 'Code block')" @pointerdown.prevent="runCommand('code-block')"><span class="block-glyph">{ }</span></button>
-      <button type="button" :title="t('行内公式', 'Inline formula')" :aria-label="t('行内公式', 'Inline formula')" @pointerdown.prevent="runCommand('inline-math')"><span class="math-glyph">ƒx</span></button>
-      <button type="button" :title="t('公式块', 'Formula block')" :aria-label="t('公式块', 'Formula block')" @pointerdown.prevent="runCommand('math-block')"><span class="math-glyph">∑</span></button>
+      <button v-if="markdownPreferences.math" type="button" :title="t('行内公式', 'Inline formula')" :aria-label="t('行内公式', 'Inline formula')" @pointerdown.prevent="runCommand('inline-math')"><span class="math-glyph">ƒx</span></button>
+      <button v-if="markdownPreferences.math" type="button" :title="t('公式块', 'Formula block')" :aria-label="t('公式块', 'Formula block')" @pointerdown.prevent="runCommand('math-block')"><span class="math-glyph">∑</span></button>
       <button type="button" :title="t('插入链接', 'Insert link')" :aria-label="t('插入链接', 'Insert link')" @pointerdown.prevent="applyLink"><AppIcon :icon="Link" :size="17" /></button>
       <label class="toolbar-select">
-        <select :aria-label="t('插入警告框', 'Insert callout')" @change="insertCallout">
+        <select v-if="markdownPreferences.callouts" :aria-label="t('插入警告框', 'Insert callout')" @change="insertCallout">
           <option value="">{{ t('提示框', 'Callout') }}</option>
           <option v-for="(_, type) in calloutTypes" :key="type" :value="type">{{ type }}</option>
         </select>
@@ -411,6 +456,7 @@ defineExpose({ getEditor: () => crepe?.editor })
 
 <style scoped>
 .visual-editor { display: flex; flex: 1; min-height: 0; flex-direction: column; background: var(--color-background-primary); }
+.hide-code-line-numbers :deep(.cm-lineNumbers) { display: none; }
 .markdown-toolbar { display: flex; align-items: center; flex-wrap: wrap; gap: 2px; min-height: 42px; padding: 5px var(--space-lg); border-bottom: 1px solid var(--color-border-subtle); background: var(--color-surface-primary); }
 .markdown-toolbar button { display: inline-grid; place-items: center; min-width: 32px; min-height: 30px; padding: 4px 8px; border-radius: var(--radius-sm); color: var(--color-text-primary); }
 .markdown-toolbar button:hover, .toolbar-select:hover { background: var(--color-background-hover); color: var(--color-text-primary); }
diff --git a/frontend/src/features/editor/headingFolding.spec.ts b/frontend/src/features/editor/headingFolding.spec.ts
new file mode 100644
index 0000000..2b4f13b
--- /dev/null
+++ b/frontend/src/features/editor/headingFolding.spec.ts
@@ -0,0 +1,32 @@
+// @vitest-environment happy-dom
+import { expect, it } from 'vitest'
+import { Schema } from '@milkdown/kit/prose/model'
+import { EditorState, TextSelection } from '@milkdown/kit/prose/state'
+import { headingSections, headingFoldTransaction } from './headingFolding'
+
+const schema = new Schema({ nodes: {
+  doc: { content: 'block+' }, text: { group: 'inline' },
+  heading: { group: 'block', content: 'inline*', attrs: { level: { default: 1 } } },
+  paragraph: { group: 'block', content: 'inline*' },
+  blockquote: { group: 'block', content: 'block+' },
+} })
+const h = (level: number, text: string) => schema.nodes.heading!.create({ level }, schema.text(text))
+const p = (text: string) => schema.nodes.paragraph!.create(null, schema.text(text))
+it('ends sections at same-or-higher headings and confines nested quotes to their parent', () => {
+  const doc = schema.nodes.doc!.create(null, [h(1, 'A'), p('a'), h(2, 'B'), p('b'), h(1, 'C'), p('c'), schema.nodes.blockquote!.create(null, [h(2, 'D'), p('d')])])
+  const sections = headingSections(doc)
+  expect(sections.map(section => doc.nodeAt(section.from)?.textContent)).toEqual(['A', 'B', 'C', 'D'])
+  expect(sections[0]!.end).toBe(sections[2]!.from)
+  expect(sections[1]!.end).toBe(sections[2]!.from)
+  expect(sections[3]!.end).toBe(doc.content.size - 1)
+})
+it('moves the caret out of collapsed content without changing document content or history', () => {
+  const doc = schema.nodes.doc!.create(null, [h(1, 'A'), p('body'), h(1, 'B')])
+  const state = EditorState.create({ doc, selection: TextSelection.create(doc, 5) })
+  const tr = headingFoldTransaction(state, 'all')!
+  expect(tr.doc.eq(doc)).toBe(true)
+  expect(tr.docChanged).toBe(false)
+  expect(tr.selection.from).toBe(1)
+  expect(tr.getMeta('addToHistory')).toBe(false)
+  expect(headingSections(doc)).toHaveLength(1)
+})
diff --git a/frontend/src/features/editor/headingFolding.ts b/frontend/src/features/editor/headingFolding.ts
new file mode 100644
index 0000000..c97f1b0
--- /dev/null
+++ b/frontend/src/features/editor/headingFolding.ts
@@ -0,0 +1,119 @@
+import { $prose } from '@milkdown/kit/utils'
+import { Plugin, PluginKey, TextSelection, type EditorState } from '@milkdown/kit/prose/state'
+import { Decoration, DecorationSet } from '@milkdown/kit/prose/view'
+import type { Node } from '@milkdown/kit/prose/model'
+import { t } from '@/i18n'
+
+export const headingFoldKey = new PluginKey<Set<number>>('heading-folding')
+type Section = { from: number; body: number; end: number; level: number }
+const sectionCache = new WeakMap<Node, Section[]>()
+/** A section ends at the next sibling heading of the same or a higher rank. */
+export function headingSections(doc: Node): Section[] {
+  const cached = sectionCache.get(doc)
+  if (cached) return cached
+  const sections: Section[] = []
+  function visit(parent: Node, start: number) {
+    const children: { node: Node; pos: number }[] = []
+    parent.forEach((node, offset) => children.push({ node, pos: start + offset }))
+    const following: { pos: number; level: number }[] = []
+    for (let i = children.length - 1; i >= 0; i--) {
+      const { node, pos } = children[i]!
+      if (node.type.name === 'heading') {
+        while (following.length && following[following.length - 1]!.level > node.attrs.level) following.pop()
+        const next = following[following.length - 1]
+        const body = pos + node.nodeSize
+        const end = next?.pos ?? start + parent.content.size
+        if (end > body) sections.push({ from: pos, body, end, level: Number(node.attrs.level) })
+        following.push({ pos, level: Number(node.attrs.level) })
+      }
+      if (!node.isTextblock && node.childCount) visit(node, pos + 1)
+    }
+  }
+  visit(doc, 0)
+  sections.sort((a, b) => a.from - b.from)
+  sectionCache.set(doc, sections)
+  return sections
+}
+
+export function headingFoldTransaction(state: EditorState, action: 'toggle' | 'all' | 'none', position?: number) {
+  const sections = headingSections(state.doc)
+  const folded = new Set(headingFoldKey.getState(state) ?? [])
+  if (action === 'none') folded.clear()
+  else if (action === 'all') sections.forEach(section => folded.add(section.from))
+  else {
+    const section = position === undefined
+      ? sections.filter(item => item.from <= state.selection.from && item.end >= state.selection.from).pop()
+      : sections.find(item => item.from === position)
+    if (!section) return null
+    if (folded.has(section.from)) folded.delete(section.from)
+    else folded.add(section.from)
+  }
+  const tr = state.tr
+  const enclosing = sections.find(section => folded.has(section.from) && state.selection.to >= section.body && state.selection.from < section.end)
+  if (enclosing) tr.setSelection(TextSelection.near(state.doc.resolve(enclosing.from + 1)))
+  return tr.setMeta(headingFoldKey, folded).setMeta('addToHistory', false)
+}
+
+export const headingFoldingPlugin = $prose(() => new Plugin<Set<number>>({
+  key: headingFoldKey,
+  state: {
+    init: () => new Set(),
+    apply(tr, previous) {
+      const explicit = tr.getMeta(headingFoldKey) as Set<number> | undefined
+      if (explicit) return explicit
+      const sections = headingSections(tr.doc)
+      const mapped = new Set<number>()
+      for (const old of previous) {
+        const result = tr.mapping.mapResult(old, 1)
+        if (!result.deleted && sections.some(section => section.from === result.pos)) mapped.add(result.pos)
+      }
+      // Outline jumps, find and keyboard navigation must never leave a hidden caret.
+      if (tr.selectionSet || tr.docChanged) {
+        for (const section of sections) if (tr.selection.to >= section.body && tr.selection.from < section.end) mapped.delete(section.from)
+      }
+      return mapped
+    },
+  },
+  props: {
+    decorations(state) {
+      const folded = headingFoldKey.getState(state) ?? new Set<number>()
+      const sections = headingSections(state.doc)
+      const decorations: Decoration[] = []
+      for (const section of sections) {
+        const collapsed = folded.has(section.from)
+        decorations.push(Decoration.widget(section.from + 1, view => {
+          const button = document.createElement('button')
+          button.type = 'button'; button.className = 'heading-fold-toggle'; button.contentEditable = 'false'
+          button.textContent = collapsed ? '▸' : '▾'
+          button.setAttribute('aria-expanded', String(!collapsed))
+          button.setAttribute('aria-label', `${collapsed ? t('展开', 'Expand') : t('折叠', 'Collapse')} H${section.level} ${state.doc.nodeAt(section.from)?.textContent ?? ''}`)
+          button.onmousedown = event => event.preventDefault()
+          button.onclick = event => {
+            event.preventDefault()
+            const tr = headingFoldTransaction(view.state, 'toggle', section.from)
+            if (tr) view.dispatch(tr)
+          }
+          return button
+        }, { key: `${section.from}:${collapsed}:${state.doc.nodeAt(section.from)?.textContent}`, side: -1, stopEvent: () => true }))
+      }
+      const hidden: { body: number; end: number }[] = []
+      for (const section of sections) {
+        if (!folded.has(section.from)) continue
+        const previous = hidden[hidden.length - 1]
+        if (previous && section.body <= previous.end) previous.end = Math.max(previous.end, section.end)
+        else hidden.push({ body: section.body, end: section.end })
+      }
+      let rangeIndex = 0
+      state.doc.descendants((node, pos) => {
+        if (!node.isBlock) return
+        while (hidden[rangeIndex] && pos >= hidden[rangeIndex]!.end) rangeIndex++
+        const range = hidden[rangeIndex]
+        if (range && pos >= range.body && pos + node.nodeSize <= range.end) {
+          decorations.push(Decoration.node(pos, pos + node.nodeSize, { class: 'heading-fold-hidden' }))
+          return false
+        }
+      })
+      return DecorationSet.create(state.doc, decorations)
+    },
+  },
+}))
diff --git a/frontend/src/features/settings/SettingsView.vue b/frontend/src/features/settings/SettingsView.vue
index a730333..a2e3c88 100644
--- a/frontend/src/features/settings/SettingsView.vue
+++ b/frontend/src/features/settings/SettingsView.vue
@@ -5,6 +5,8 @@ const { actionDialog, resolveAction, askConfirm } = useActionDialog()
 import { computed, onMounted, ref } from 'vue'
 import type { ProviderConfig } from '@/contracts'
 import ProviderForm from './ProviderForm.vue'
+import HeadingStyleSettings from '@/features/editor/HeadingStyleSettings.vue'
+import MarkdownPreferenceSettings from '@/features/editor/MarkdownPreferenceSettings.vue'
 import ChatPersonaDialog from '@/features/chat/ChatPersonaDialog.vue'
 import ProviderLogo from './ProviderLogo.vue'
 import ModelRoutingSettings from './ModelRoutingSettings.vue'
@@ -85,7 +87,7 @@ async function chooseDefaultModel(provider: ProviderConfig, event: Event) {
     <ChatPersonaDialog v-if="showPersona" @close="showPersona = false" />
     <div v-if="activeSection === 'general'" class="panel settings-section"><h2>{{ t('通用', 'General') }}</h2><label class="setting-row"><span><strong>{{ t('恢复上次 Vault', 'Restore last Vault') }}</strong><small>{{ t('启动后自动打开最近使用的知识库', 'Open the most recently used knowledge base at startup') }}</small></span><input v-model="settingsStore.restoreLastVault" type="checkbox" /></label><div class="setting-row"><span><strong>{{ t('自动保存间隔', 'Autosave interval') }}</strong><small>{{ t('编辑停止后等待多久写入文件', 'How long to wait after editing before saving') }}</small></span><select v-model.number="settingsStore.autoSaveInterval" class="select short"><option :value="500">0.5 {{ t('秒', 'sec') }}</option><option :value="1500">1.5 {{ t('秒', 'sec') }}</option><option :value="3000">3 {{ t('秒', 'sec') }}</option></select></div><div class="setting-row"><span><strong>{{ t('界面语言', 'Interface language') }}</strong><small>{{ t('切换后立即应用到界面', 'Applied to the interface immediately') }}</small></span><select v-model="settingsStore.language" class="select short"><option value="zh-CN">简体中文</option><option value="en">English</option></select></div><div class="setting-row"><span><strong>{{ t('版本', 'Version') }}</strong><small>Desktop / AI Core</small></span><span>{{ settingsStore.appVersion }} / {{ settingsStore.aiCoreVersion }}</span></div></div>
 
-    <div v-else-if="activeSection === 'editor'" class="panel settings-section"><h2>{{ t('编辑器', 'Editor') }}</h2><div class="setting-row"><span><strong>{{ t('默认模式', 'Default mode') }}</strong><small>{{ t('新打开文件使用的编辑器模式', 'Editor mode used for newly opened files') }}</small></span><select v-model="settingsStore.defaultEditorMode" class="select short"><option value="wysiwyg">{{ t('写作与预览', 'Writing and preview') }}</option><option value="source">{{ t('Markdown 源码', 'Markdown source') }}</option></select></div><div class="setting-row"><span><strong>{{ t('字号', 'Font size') }}</strong></span><input v-model.number="themeStore.fontEditorSize" class="input short" type="number" min="12" max="32" /></div><div class="setting-row"><span><strong>{{ t('行高', 'Line height') }}</strong></span><input v-model.number="themeStore.lineHeight" class="input short" type="number" min="1.2" max="2.4" step="0.1" /></div><div class="setting-row"><span><strong>{{ t('行宽', 'Line width') }}</strong><small>{{ t('Markdown 预览最大字符宽度', 'Maximum character width for Markdown preview') }}</small></span><input v-model.number="settingsStore.editorLineWidth" class="input short" type="number" min="40" max="140" /></div><label class="setting-row"><span><strong>{{ t('拼写检查', 'Spell check') }}</strong><small>{{ t('在写作与源码编辑器中使用系统拼写检查', 'Use system spell checking in visual and source editors') }}</small></span><input v-model="settingsStore.spellCheck" type="checkbox" /></label></div>
+    <div v-else-if="activeSection === 'editor'" class="panel settings-section"><h2>{{ t('编辑器', 'Editor') }}</h2><div class="setting-row"><span><strong>{{ t('默认模式', 'Default mode') }}</strong><small>{{ t('新打开文件使用的编辑器模式', 'Editor mode used for newly opened files') }}</small></span><select v-model="settingsStore.defaultEditorMode" class="select short"><option value="wysiwyg">{{ t('写作与预览', 'Writing and preview') }}</option><option value="source">{{ t('Markdown 源码', 'Markdown source') }}</option></select></div><div class="setting-row"><span><strong>{{ t('字号', 'Font size') }}</strong></span><input v-model.number="themeStore.fontEditorSize" class="input short" type="number" min="12" max="32" /></div><div class="setting-row"><span><strong>{{ t('行高', 'Line height') }}</strong></span><input v-model.number="themeStore.lineHeight" class="input short" type="number" min="1.2" max="2.4" step="0.1" /></div><div class="setting-row"><span><strong>{{ t('行宽', 'Line width') }}</strong><small>{{ t('Markdown 预览最大字符宽度', 'Maximum character width for Markdown preview') }}</small></span><input v-model.number="settingsStore.editorLineWidth" class="input short" type="number" min="40" max="140" /></div><label class="setting-row"><span><strong>{{ t('拼写检查', 'Spell check') }}</strong><small>{{ t('在写作与源码编辑器中使用系统拼写检查', 'Use system spell checking in visual and source editors') }}</small></span><input v-model="settingsStore.spellCheck" type="checkbox" /></label><MarkdownPreferenceSettings /><HeadingStyleSettings /></div>
 
     <div v-else-if="activeSection === 'providers'" class="settings-section">
       <section class="panel provider-settings-card">
diff --git a/frontend/src/features/themes/CommunityThemePreview.vue b/frontend/src/features/themes/CommunityThemePreview.vue
index de96438..cab8cfe 100644
--- a/frontend/src/features/themes/CommunityThemePreview.vue
+++ b/frontend/src/features/themes/CommunityThemePreview.vue
@@ -5,6 +5,7 @@ import { t } from '@/i18n'
 import { getCommunityThemePreviewCss, mockCommunityThemes } from '@/services/themePackageService'
 import tokensCss from '@/styles/tokens.css?raw'
 import featuresCss from '@/styles/features.css?raw'
+import headingsCss from '@/styles/headings.css?raw'
 import calloutsCss from '@/styles/callouts.css?raw'
 import { calloutTypes } from '@/utils/callouts'
 import specimenHtml from './themeSpecimen.html?raw'
@@ -22,7 +23,7 @@ const previewDocument = computed(() => {
   policy.content = "default-src 'none'; style-src 'unsafe-inline'; img-src data:; font-src data:; base-uri 'none'; form-action 'none'"
   doc.head.append(policy)
   const style = doc.createElement('style')
-  style.textContent = `${tokensCss}\n${featuresCss}\n${calloutsCss}\n${props.css ?? getCommunityThemePreviewCss(props.themeId)}\nhtml { height:100% !important; overflow-y:auto !important; overflow-x:hidden !important; overscroll-behavior:contain; } body { height:auto !important; min-height:100%; overflow:visible !important; margin:0; padding:24px; background:var(--color-background-primary); color:var(--color-text-primary); font:16px/1.6 system-ui; } article { min-width:0; } .theme-specimen { display:grid; gap:16px; margin-top:20px; } .surface-nested { padding:12px; border:1px solid var(--color-border-default); border-radius:var(--radius-md); } .specimen-markdown { overflow:auto; } .specimen-markdown code { background:var(--color-code-background, var(--color-background-secondary)); color:var(--color-code-text, var(--color-text-primary)); padding:3px 6px; border-radius:4px; } .specimen-markdown pre { padding:12px; background:var(--color-background-secondary); } .specimen-markdown blockquote { border-left:3px solid var(--color-accent-primary); padding-left:12px; } .specimen-markdown table { width:100%; border-collapse:collapse; } .specimen-markdown td,.specimen-markdown th { padding:8px; border:1px solid var(--color-border-default); } .specimen-markdown th { background:var(--color-markdown-table-header); } .specimen-chart > div { display:flex; align-items:flex-end; gap:12px; height:100px; border-bottom:1px solid var(--color-border-default); } .specimen-chart span { width:36px; } .specimen-long { overflow-wrap:anywhere; } @media(max-width:480px) { body { padding:12px; } .form-grid { grid-template-columns:minmax(0,1fr); } }`
+  style.textContent = `${tokensCss}\n${featuresCss}\n${calloutsCss}\n${headingsCss}\n${props.css ?? getCommunityThemePreviewCss(props.themeId)}\nhtml { height:100% !important; overflow-y:auto !important; overflow-x:hidden !important; overscroll-behavior:contain; } body { height:auto !important; min-height:100%; overflow:visible !important; margin:0; padding:24px; background:var(--color-background-primary); color:var(--color-text-primary); font:16px/1.6 system-ui; } article { min-width:0; } .theme-specimen { display:grid; gap:16px; margin-top:20px; } .surface-nested { padding:12px; border:1px solid var(--color-border-default); border-radius:var(--radius-md); } .specimen-markdown { overflow:auto; } .specimen-markdown code { background:var(--color-code-background, var(--color-background-secondary)); color:var(--color-code-text, var(--color-text-primary)); padding:3px 6px; border-radius:4px; } .specimen-markdown pre { padding:12px; background:var(--color-background-secondary); } .specimen-markdown blockquote { border-left:3px solid var(--color-accent-primary); padding-left:12px; } .specimen-markdown table { width:100%; border-collapse:collapse; } .specimen-markdown td,.specimen-markdown th { padding:8px; border:1px solid var(--color-border-default); } .specimen-markdown th { background:var(--color-markdown-table-header); } .specimen-chart > div { display:flex; align-items:flex-end; gap:12px; height:100px; border-bottom:1px solid var(--color-border-default); } .specimen-chart span { width:36px; } .specimen-long { overflow-wrap:anywhere; } @media(max-width:480px) { body { padding:12px; } .form-grid { grid-template-columns:minmax(0,1fr); } }`
 
   doc.head.append(style)
   const article = doc.createElement('article')
diff --git a/frontend/src/features/themes/ThemesView.spec.ts b/frontend/src/features/themes/ThemesView.spec.ts
index ea528a1..28f9fc7 100644
--- a/frontend/src/features/themes/ThemesView.spec.ts
+++ b/frontend/src/features/themes/ThemesView.spec.ts
@@ -96,7 +96,7 @@ it.each(mockCommunityThemes)('previews uninstalled $theme_id using its actual CS
 
 it('offers and applies the paper theme update without discarding the active theme', async () => {
   const store = useThemeStore()
-  const old = await inspectThemePackage(paperPackage.replace('version: 1.7.0', 'version: 1.6.1'))
+  const old = await inspectThemePackage(paperPackage.replace('version: 1.8.0', 'version: 1.6.1'))
   await store.installThemeFromInspection(old.manifest, old.css)
   store.applyTheme('paper-moments')
   wrapper = mount(ThemesView, { global: { stubs: { MarkdownContent: true } } })
@@ -105,6 +105,6 @@ it('offers and applies the paper theme update without discarding the active them
   const card = wrapper.findAll('article.theme-card').find(item => item.text().includes('Paper Moments'))!
   await card.findAll('button').find(button => button.text() === '更新')!.trigger('click')
   await flushPromises()
-  expect(store.allThemes.find(theme => theme.theme_id === 'paper-moments')?.version).toBe('1.7.0')
+  expect(store.allThemes.find(theme => theme.theme_id === 'paper-moments')?.version).toBe('1.8.0')
   expect(document.getElementById('theme-style-paper-moments')!.textContent).toContain('.surface-nested')
 })
diff --git a/frontend/src/features/themes/ThemesView.vue b/frontend/src/features/themes/ThemesView.vue
index a000c50..f5e63a8 100644
--- a/frontend/src/features/themes/ThemesView.vue
+++ b/frontend/src/features/themes/ThemesView.vue
@@ -1,4 +1,5 @@
 <script setup lang="ts">
+import HeadingStyleSettings from '@/features/editor/HeadingStyleSettings.vue'
 import AppDialog from '@/components/common/AppDialog.vue'
 import { computed, onMounted, onBeforeUnmount, ref } from 'vue'
 import MarkdownContent from '@/components/common/MarkdownContent.vue'
@@ -222,6 +223,7 @@ onMounted(() => {
         <div class="field"><label>{{ t('字体', 'Font') }}</label><select v-model="themeStore.fontEditorFamily" class="select"><option value="system-ui">{{ t('系统字体', 'System font') }}</option><option value="serif">{{ t('衬线字体', 'Serif') }}</option><option value="var(--font-ui-mono)">{{ t('等宽字体', 'Monospace') }}</option></select></div>
         <div class="field"><label>{{ t('代码块样式', 'Code block style') }}</label><select v-model="themeStore.codeBlockTheme" class="select"><option value="auto">{{ t('跟随主题', 'Follow theme') }}</option><option value="github-light">GitHub Light</option><option value="github-dark">GitHub Dark</option></select><small>{{ t('Markdown 渲染使用对应的 Shiki GitHub 主题', 'Markdown rendering uses the matching Shiki GitHub theme') }}</small></div>
       </div>
+      <HeadingStyleSettings />
       <div class="editor-preview" :style="{ fontSize: `${themeStore.fontEditorSize}px`, lineHeight: themeStore.lineHeight, fontFamily: themeStore.fontEditorFamily }">
         <div class="preview-heading"><h3>{{ t('主题预览', 'Theme Preview') }}</h3><span class="badge info">{{ codeThemeLabel }}</span></div>
         <p>{{ t('知识的价值不只在于保存，更在于被重新发现和使用。', 'Knowledge gains value when it can be rediscovered and used.') }}</p>
diff --git a/frontend/src/features/themes/themeSpecimen.html b/frontend/src/features/themes/themeSpecimen.html
index b2e6d02..a5f2805 100644
--- a/frontend/src/features/themes/themeSpecimen.html
+++ b/frontend/src/features/themes/themeSpecimen.html
@@ -17,3 +17,6 @@ console.log(note);</code></pre><table><thead><tr><th>名称</th><th>状态</th><
   <figure class="specimen-chart"><figcaption>数据配色示例</figcaption><div role="img" aria-label="本地用量 30，提供商用量 70"><span style="height:30%;background:var(--color-accent-primary)"></span><span style="height:70%;background:var(--color-accent-secondary)"></span></div></figure>
   <p class="subtle specimen-long">超长模型标识：provider/model-with-a-very-long-identifier-for-layout-validation-012345678901234567890123456789</p>
 </div>
+
+<section class="surface-nested markdown-preferences"><h2>Markdown 语法预设</h2><label>标题样式 <select class="select"><option>ATX (#)</option><option>Setext</option></select></label><label><input type="checkbox" checked> 警告框与提示框</label><button class="button-secondary">保存为预设</button></section>
+<section class="milkdown"><div class="ProseMirror"><h2><button class="heading-fold-toggle" aria-expanded="true" aria-label="折叠示例标题"></button>悬停查看折叠箭头</h2><p>折叠按钮跟随主题，键盘聚焦时也可见。</p></div></section>
diff --git a/frontend/src/features/workspace/FileTreePanel.vue b/frontend/src/features/workspace/FileTreePanel.vue
index 3855b06..3cfbc3e 100644
--- a/frontend/src/features/workspace/FileTreePanel.vue
+++ b/frontend/src/features/workspace/FileTreePanel.vue
@@ -216,6 +216,7 @@ function containingFolder(path: string): string {
 
 <template>
   <section class="file-tree-panel" @click="closeContextMenu" @keydown.esc="closeContextMenu" @wheel.passive="revealSearch">
+    <p v-if="workspaceStore.treeRefreshError" class="subtle" role="status">{{ t('文件树暂未同步，将自动重试。', 'File tree sync delayed; retrying automatically.') }}</p>
     <ActionDialog v-if="actionDialog" v-bind="actionDialog" @resolve="resolveAction" />
     <div class="workspace-tabs" role="tablist" :aria-label="t('工作区导航', 'Workspace navigation')" @keydown="navigateTabs">
       <button id="workspace-files-tab" role="tab" aria-controls="workspace-files-panel" :aria-selected="activeTab === 'files'" :tabindex="activeTab === 'files' ? 0 : -1" @click="switchTab('files')">{{ t('文件', 'Files') }}</button>
diff --git a/frontend/src/services/editorCommandService.ts b/frontend/src/services/editorCommandService.ts
index f43c118..5884e81 100644
--- a/frontend/src/services/editorCommandService.ts
+++ b/frontend/src/services/editorCommandService.ts
@@ -9,6 +9,7 @@ export const editorCommandIds = [
   'editor.font-size', 'editor.insert-markdown', 'editor.import-note-properties',
   'editor.metadata.edit', 'editor.metadata.title', 'editor.metadata.tags',
   'editor.reference-link', 'editor.html', 'editor.undo', 'editor.redo',
+  'editor.heading.toggle-fold', 'editor.heading.fold-all', 'editor.heading.unfold-all',
 ] as const
 export type EditorCommandId = typeof editorCommandIds[number]
 export type CommandResult = { ok: true } | { ok: false; reason: 'unsupported' | 'unavailable' | 'invalid-params' | 'failed' }
diff --git a/frontend/src/services/noteService.ts b/frontend/src/services/noteService.ts
index 30e57bd..58f89ec 100644
--- a/frontend/src/services/noteService.ts
+++ b/frontend/src/services/noteService.ts
@@ -25,7 +25,7 @@ export async function createNote(data: {
 
 export async function updateNote(
   noteId: string,
-  data: { title?: string; markdown?: string; tags?: string[] }
+  data: { title?: string; markdown?: string; tags?: string[]; expected_content_hash?: string }
 ): Promise<ApiNote> {
   return apiClient.patch(`/api/notes/${noteId}`, data)
 }
diff --git a/frontend/src/services/themePackageService.ts b/frontend/src/services/themePackageService.ts
index 7d62703..faf6424 100644
--- a/frontend/src/services/themePackageService.ts
+++ b/frontend/src/services/themePackageService.ts
@@ -361,7 +361,7 @@ export const mockCommunityThemes: ThemeManifest[] = [
   {
     theme_id: 'ocean-blue',
     name: 'Ocean Blue',
-    version: '1.4.0',
+    version: '1.5.0',
     author: 'community',
     description: '宁静的海洋蓝色主题，适合长时间阅读',
     min_app_version: '0.2.0',
@@ -373,7 +373,7 @@ export const mockCommunityThemes: ThemeManifest[] = [
   {
     theme_id: 'midnight-purple',
     name: 'Midnight Purple',
-    version: '2.2.0',
+    version: '2.3.0',
     author: 'night-owl',
     description: '深紫色暗夜主题，适合编码',
     min_app_version: '0.2.0',
diff --git a/frontend/src/services/workspaceService.ts b/frontend/src/services/workspaceService.ts
index c412de3..5fec41d 100644
--- a/frontend/src/services/workspaceService.ts
+++ b/frontend/src/services/workspaceService.ts
@@ -19,6 +19,7 @@ export interface VaultInfo {
 }
 
 let cachedTree: FileNode[] | null = null
+let treeRequestVersion = 0
 const noteIdByPath = new Map<string, string>()
 const typeByPath = new Map<string, FileNode['type']>()
 
@@ -88,6 +89,7 @@ export async function getRecentVaults(): Promise<VaultInfo[]> {
 }
 
 export async function openVault(path: string): Promise<VaultInfo> {
+  treeRequestVersion++
   const snapshot = await apiClient.post<ApiWorkspaceSnapshot>('/api/workspace/open', { path }, { timeoutMs: 15000 })
   cacheEntries(snapshot.items)
   return {
@@ -104,7 +106,9 @@ export async function createVault(path: string, name: string): Promise<VaultInfo
 }
 
 export async function refreshTree(): Promise<FileNode[]> {
-  const entries = await apiClient.get<ApiWorkspaceEntry[]>('/api/workspace/tree')
+  const version = ++treeRequestVersion
+  const entries = await apiClient.get<ApiWorkspaceEntry[]>('/api/workspace/tree', { timeoutMs: 10000 })
+  if (version !== treeRequestVersion) return cachedTree ?? []
   return cacheEntries(entries)
 }
 
@@ -122,10 +126,12 @@ export async function getNoteId(filePath: string): Promise<string> {
   return requireNoteId(filePath)
 }
 
-export async function saveFileContent(filePath: string, content: string): Promise<void> {
+export async function saveFileContent(filePath: string, content: string, expectedContent?: string): Promise<void> {
   const metadata = splitNoteMetadata(content)
+  const expectedHash = expectedContent === undefined ? undefined : Array.from(new Uint8Array(await crypto.subtle.digest('SHA-256', new TextEncoder().encode(expectedContent)))).map(byte => byte.toString(16).padStart(2, '0')).join('')
   await noteService.updateNote(await requireNoteId(filePath), {
     markdown: content,
+    ...(expectedHash ? { expected_content_hash: expectedHash } : {}),
     // Explicit [] clears the index; absent tags retain API-managed tags.
     ...(metadata?.hasTags ? { tags: metadata.tags } : {}),
   })
diff --git a/frontend/src/stores/editor.ts b/frontend/src/stores/editor.ts
index 1d104a2..1cf8ce0 100644
--- a/frontend/src/stores/editor.ts
+++ b/frontend/src/stores/editor.ts
@@ -3,10 +3,13 @@ import { ref, computed } from 'vue'
 import type { SaveStatus } from '@/contracts'
 import * as workspaceService from '@/services/workspaceService'
 import { t } from '@/i18n'
+import { ApiErrorClass } from '@/services/apiClient'
 
 export const useEditorStore = defineStore('editor', () => {
   const mode = ref<'wysiwyg' | 'source'>('wysiwyg')
   const content = ref('')
+  const contentRevision = ref(0)
+  let diskContent: string | undefined
   const saveStatus = ref<SaveStatus>('idle')
   const lastSavedAt = ref<string | null>(null)
   const currentNoteId = ref<string | null>(null)
@@ -35,13 +38,14 @@ export const useEditorStore = defineStore('editor', () => {
 
   function updateContent(newContent: string) {
     content.value = newContent
-    saveStatus.value = 'dirty'
+    if (saveStatus.value !== 'conflict' && saveStatus.value !== 'external_changed') saveStatus.value = 'dirty'
   }
 
   let saveTimer: ReturnType<typeof setTimeout> | null = null
   let pendingSave: Promise<void> | null = null
 
   function scheduleAutoSave(delay = 1500) {
+    if (saveStatus.value === 'conflict' || saveStatus.value === 'external_changed') return
     if (saveTimer) clearTimeout(saveTimer)
     saveTimer = setTimeout(() => {
       saveTimer = null
@@ -51,20 +55,23 @@ export const useEditorStore = defineStore('editor', () => {
 
   async function save() {
     if (!currentFilePath.value) return
+    if (saveStatus.value === 'conflict' || saveStatus.value === 'external_changed') return
     if (pendingSave) return pendingSave
     // 保存路径与正文都取快照；请求完成时用户可能已继续输入或切换文件。
     const targetPath = currentFilePath.value
     const snapshot = content.value
+    const baseline = diskContent
     saveStatus.value = 'saving'
     pendingSave = (async () => {
       try {
-        await workspaceService.saveFileContent(targetPath, snapshot)
+        await workspaceService.saveFileContent(targetPath, snapshot, baseline)
         if (currentFilePath.value === targetPath) {
+          diskContent = snapshot
           saveStatus.value = content.value === snapshot ? 'saved' : 'dirty'
           lastSavedAt.value = new Date().toISOString()
         }
-      } catch {
-        if (currentFilePath.value === targetPath) saveStatus.value = 'save_failed'
+      } catch (error) {
+        if (currentFilePath.value === targetPath) saveStatus.value = error instanceof ApiErrorClass && error.code === 'NOTE_CONTENT_CONFLICT' ? 'conflict' : 'save_failed'
       } finally {
         pendingSave = null
         if (currentFilePath.value === targetPath && saveStatus.value === 'dirty') scheduleAutoSave()
@@ -86,7 +93,7 @@ export const useEditorStore = defineStore('editor', () => {
     }
     if (pendingSave) await pendingSave
     if (saveStatus.value === 'dirty' || saveStatus.value === 'save_failed') await save()
-    if (saveStatus.value === 'dirty' || saveStatus.value === 'save_failed') {
+    if (['dirty', 'save_failed', 'conflict', 'external_changed'].includes(saveStatus.value)) {
       throw new Error(t('当前文件保存失败，已阻止切换以避免内容丢失。', 'The current file could not be saved. Switching was blocked to prevent data loss.'))
     }
     // 版本号使较慢的旧读取不能覆盖用户后选择的新文件。
@@ -102,6 +109,7 @@ export const useEditorStore = defineStore('editor', () => {
       currentFilePath.value = filePath
       currentNoteId.value = loadedNoteId
       content.value = loadedContent
+      diskContent = loadedContent
       saveStatus.value = 'saved'
       lastSavedAt.value = new Date().toISOString()
     } catch (error) {
@@ -122,13 +130,37 @@ export const useEditorStore = defineStore('editor', () => {
   }
 
   function setExternalChanged() {
-    if (saveStatus.value === 'dirty') {
+    if (saveTimer) { clearTimeout(saveTimer); saveTimer = null }
+    if (saveStatus.value === 'dirty' || saveStatus.value === 'save_failed' || saveStatus.value === 'conflict') {
       saveStatus.value = 'conflict'
     } else {
       saveStatus.value = 'external_changed'
     }
   }
 
+  async function checkExternalFile() {
+    if (!currentFilePath.value || pendingSave || diskContent === undefined || saveStatus.value === 'conflict') return
+    const path = currentFilePath.value, baseline = diskContent
+    try {
+      const latest = await workspaceService.readFileContent(path)
+      if (path !== currentFilePath.value || pendingSave || diskContent !== baseline || latest === baseline) return
+      if (content.value === baseline && saveStatus.value === 'saved') {
+        content.value = latest; diskContent = latest; contentRevision.value++
+      } else {
+        setExternalChanged(); saveStatus.value = 'conflict'
+      }
+    } catch { /* Tree polling reports missing files; transient network errors retain edits. */ }
+  }
+
+  async function reloadExternalFile() {
+    const path = currentFilePath.value, snapshot = content.value
+    if (!path || pendingSave) return
+    const latest = await workspaceService.readFileContent(path)
+    if (path !== currentFilePath.value || content.value !== snapshot || pendingSave) return
+    if (saveTimer) { clearTimeout(saveTimer); saveTimer = null }
+    content.value = latest; diskContent = latest; saveStatus.value = 'saved'; contentRevision.value++
+  }
+
   // TODO(editor): 桌面文件监听接入后提供冲突对比/合并界面，而非只阻止切换。
 
   function closeFile() {
@@ -137,6 +169,7 @@ export const useEditorStore = defineStore('editor', () => {
     currentFilePath.value = null
     currentNoteId.value = null
     content.value = ''
+    diskContent = undefined
     saveStatus.value = 'idle'
     lastSavedAt.value = null
     highlightBlockId.value = null
@@ -153,6 +186,9 @@ export const useEditorStore = defineStore('editor', () => {
     jumpToHeading,
     mode,
     content,
+    contentRevision,
+    checkExternalFile,
+    reloadExternalFile,
     saveStatus,
     lastSavedAt,
     currentNoteId,
diff --git a/frontend/src/stores/editorSave.spec.ts b/frontend/src/stores/editorSave.spec.ts
index e493358..9f0026d 100644
--- a/frontend/src/stores/editorSave.spec.ts
+++ b/frontend/src/stores/editorSave.spec.ts
@@ -6,6 +6,30 @@ import * as workspace from '@/services/workspaceService'
 
 afterEach(() => { vi.restoreAllMocks(); vi.useRealTimers() })
 
+it('reloads clean external changes but preserves unsaved edits and blocks overwrite', async () => {
+  setActivePinia(createPinia())
+  vi.spyOn(workspace, 'getNoteId').mockResolvedValue('id')
+  const read = vi.spyOn(workspace, 'readFileContent').mockResolvedValue('original')
+  const write = vi.spyOn(workspace, 'saveFileContent').mockResolvedValue()
+  const store = useEditorStore()
+  await store.loadFile('/draft.md')
+  read.mockResolvedValue('external')
+  await store.checkExternalFile()
+  expect(store.content).toBe('external')
+  expect(store.contentRevision).toBe(1)
+  store.updateContent('my unsaved changes')
+  read.mockResolvedValue('new external')
+  await store.checkExternalFile()
+  expect(store.saveStatus).toBe('conflict')
+  expect(store.content).toBe('my unsaved changes')
+  store.updateContent('keep editing')
+  await store.save()
+  expect(write).not.toHaveBeenCalled()
+  await store.reloadExternalFile()
+  expect(store.content).toBe('new external')
+  expect(store.saveStatus).toBe('saved')
+})
+
 it('saves text typed while the previous save is still pending', async () => {
   vi.useFakeTimers()
   setActivePinia(createPinia())
@@ -20,6 +44,6 @@ it('saves text typed while the previous save is still pending', async () => {
   await saving
   expect(store.saveStatus).toBe('dirty')
   await vi.advanceTimersByTimeAsync(1500)
-  expect(write).toHaveBeenLastCalledWith('/draft.md', 'latest')
+  expect(write).toHaveBeenLastCalledWith('/draft.md', 'latest', 'first')
   expect(store.saveStatus).toBe('saved')
 })
diff --git a/frontend/src/stores/headingAppearance.spec.ts b/frontend/src/stores/headingAppearance.spec.ts
new file mode 100644
index 0000000..cfd7043
--- /dev/null
+++ b/frontend/src/stores/headingAppearance.spec.ts
@@ -0,0 +1,28 @@
+// @vitest-environment happy-dom
+import { beforeEach, expect, it } from 'vitest'
+import { createPinia, setActivePinia } from 'pinia'
+import { nextTick } from 'vue'
+import { normalizeHeadingAppearance, useHeadingAppearanceStore } from './headingAppearance'
+beforeEach(() => { localStorage.clear(); setActivePinia(createPinia()) })
+it('persists heading preferences and restores theme defaults without residual overrides', async () => {
+  const store = useHeadingAppearanceStore()
+  expect(store.cssVariables).toEqual({})
+  store.preferences.custom = true
+  store.preferences.levels[1]!.size = 35
+  store.preferences.levels[1]!.weight = 400
+  await nextTick()
+  setActivePinia(createPinia())
+  const restored = useHeadingAppearanceStore()
+  expect(restored.cssVariables['--heading-2-size']).toBe('35px')
+  expect(restored.cssVariables['--heading-2-weight']).toBe('400')
+  restored.reset()
+  expect(restored.cssVariables).toEqual({})
+})
+it('rejects invalid storage and limits values before applying CSS', () => {
+  localStorage.setItem('editor-heading-appearance', 'invalid')
+  expect(useHeadingAppearanceStore().preferences.custom).toBe(false)
+  const result = normalizeHeadingAppearance({ custom: true, family: 'url(unsafe)', levels: [{ size: 9999, weight: 2 }, { size: NaN }] })
+  expect(result.family).toBe('inherit')
+  expect(result.levels[0]).toEqual({ size: 72, weight: 700 })
+  expect(result.levels[1]!.size).toBe(28)
+})
diff --git a/frontend/src/stores/headingAppearance.ts b/frontend/src/stores/headingAppearance.ts
new file mode 100644
index 0000000..ed6ce4d
--- /dev/null
+++ b/frontend/src/stores/headingAppearance.ts
@@ -0,0 +1,40 @@
+import { defineStore } from 'pinia'
+import { computed, ref, watch } from 'vue'
+import '@/styles/headings.css'
+
+const key = 'editor-heading-appearance'
+export const defaultHeadingSizes = [32, 28, 24, 21, 18, 16]
+export function normalizeHeadingAppearance(value: unknown) {
+  const raw = value && typeof value === 'object' ? value as Record<string, unknown> : {}
+  const levels = Array.isArray(raw.levels) ? raw.levels : []
+  return {
+    custom: raw.custom === true,
+    family: ['inherit', 'serif', 'sans-serif', 'monospace'].includes(String(raw.family)) ? String(raw.family) : 'inherit',
+    levels: defaultHeadingSizes.map((size, index) => {
+      const item = levels[index] ?? {}
+      return {
+        size: typeof item.size === 'number' && Number.isFinite(item.size) ? Math.min(72, Math.max(12, item.size)) : size,
+        weight: [400, 500, 600, 700, 800].includes(item.weight) ? Number(item.weight) : 700,
+      }
+    }),
+  }
+}
+
+export const useHeadingAppearanceStore = defineStore('heading-appearance', () => {
+  let saved: unknown
+  try { saved = JSON.parse(localStorage.getItem(key) ?? '{}') } catch { saved = {} }
+  const preferences = ref(normalizeHeadingAppearance(saved))
+  watch(preferences, value => localStorage.setItem(key, JSON.stringify(normalizeHeadingAppearance(value))), { deep: true })
+  const cssVariables = computed(() => {
+    const normalized = normalizeHeadingAppearance(preferences.value)
+    if (!normalized.custom) return {}
+    const result: Record<string, string> = { '--heading-family': normalized.family }
+    normalized.levels.forEach((item, index) => {
+      result[`--heading-${index + 1}-size`] = `${item.size}px`
+      result[`--heading-${index + 1}-weight`] = String(item.weight)
+    })
+    return result
+  })
+  function reset() { preferences.value = normalizeHeadingAppearance({}) }
+  return { preferences, cssVariables, reset }
+})
diff --git a/frontend/src/stores/markdownPreferences.spec.ts b/frontend/src/stores/markdownPreferences.spec.ts
new file mode 100644
index 0000000..4abbbdd
--- /dev/null
+++ b/frontend/src/stores/markdownPreferences.spec.ts
@@ -0,0 +1,20 @@
+// @vitest-environment happy-dom
+import { beforeEach, expect, it } from 'vitest'
+import { createPinia, setActivePinia } from 'pinia'
+import { nextTick } from 'vue'
+import { useMarkdownPreferencesStore, markdownPresets } from './markdownPreferences'
+beforeEach(() => { localStorage.clear(); setActivePinia(createPinia()) })
+it('saves, replaces and restores named syntax presets', async () => {
+  const store = useMarkdownPreferencesStore()
+  store.preferences.heading = 'setext'
+  store.preferences.bullet = '+'
+  expect(store.savePreset('我的格式')).toBe(true)
+  store.apply(markdownPresets.plain)
+  expect(store.normalized.callouts).toBe(false)
+  store.apply(store.customPresets[0]!.preferences)
+  expect(store.normalized.heading).toBe('setext')
+  await nextTick()
+  setActivePinia(createPinia())
+  expect(useMarkdownPreferencesStore().normalized.bullet).toBe('+')
+  expect(useMarkdownPreferencesStore().customPresets[0]!.name).toBe('我的格式')
+})
diff --git a/frontend/src/stores/markdownPreferences.ts b/frontend/src/stores/markdownPreferences.ts
new file mode 100644
index 0000000..85ab08c
--- /dev/null
+++ b/frontend/src/stores/markdownPreferences.ts
@@ -0,0 +1,49 @@
+import { defineStore } from 'pinia'
+import { computed, ref, watch } from 'vue'
+
+export interface MarkdownPreferences {
+  heading: 'atx' | 'setext'; bullet: '-' | '*' | '+'; incrementList: boolean
+  fence: '`' | '~'; math: boolean; callouts: boolean; diagrams: boolean; autoLinks: boolean
+  lineNumbers: boolean; wrapCode: boolean; indent: number; defaultLanguage: string
+}
+export const defaultMarkdownPreferences: MarkdownPreferences = {
+  heading: 'atx', bullet: '-', incrementList: true, fence: '`', math: true, callouts: true,
+  diagrams: true, autoLinks: true, lineNumbers: true, wrapCode: false, indent: 4, defaultLanguage: '',
+}
+export function normalizeMarkdownPreferences(value: unknown): MarkdownPreferences {
+  const raw = value && typeof value === 'object' ? value as Record<string, unknown> : {}
+  const result = { ...defaultMarkdownPreferences }
+  for (const key of ['incrementList','math','callouts','diagrams','autoLinks','lineNumbers','wrapCode'] as const) if (typeof raw[key] === 'boolean') result[key] = raw[key]
+  result.heading = raw.heading === 'setext' ? 'setext' : 'atx'
+  result.bullet = raw.bullet === '*' || raw.bullet === '+' ? raw.bullet : '-'
+  result.fence = raw.fence === '~' ? '~' : '`'
+  result.indent = [2,4,8].includes(Number(raw.indent)) ? Number(raw.indent) : 4
+  result.defaultLanguage = typeof raw.defaultLanguage === 'string' && /^[\w+-]{0,40}$/.test(raw.defaultLanguage) ? raw.defaultLanguage : ''
+  return result
+}
+export const markdownPresets = {
+  extended: defaultMarkdownPreferences,
+  github: { ...defaultMarkdownPreferences, math: false },
+  plain: { ...defaultMarkdownPreferences, math: false, callouts: false, diagrams: false, autoLinks: false },
+}
+const key = 'markdown-preferences'
+export const useMarkdownPreferencesStore = defineStore('markdown-preferences', () => {
+  let saved: Record<string, unknown> = {}
+  try { saved = JSON.parse(localStorage.getItem(key) ?? '{}') ?? {} } catch { /* defaults */ }
+  const preferences = ref(normalizeMarkdownPreferences(saved.preferences))
+  const customPresets = ref<{ name: string; preferences: MarkdownPreferences }[]>(Array.isArray(saved.presets)
+    ? saved.presets.filter(item => item && typeof item.name === 'string').slice(0, 20).map(item => ({ name: item.name.slice(0, 40), preferences: normalizeMarkdownPreferences(item.preferences) })) : [])
+  const normalized = computed(() => normalizeMarkdownPreferences(preferences.value))
+  watch([preferences, customPresets], () => localStorage.setItem(key, JSON.stringify({ preferences: normalized.value, presets: customPresets.value })), { deep: true })
+  function apply(value: unknown) { preferences.value = normalizeMarkdownPreferences(value) }
+  function savePreset(name: string) {
+    name = name.trim().slice(0, 40)
+    if (!name) return false
+    const existing = customPresets.value.find(item => item.name === name)
+    if (existing) existing.preferences = { ...normalized.value }
+    else if (customPresets.value.length < 20) customPresets.value.push({ name, preferences: { ...normalized.value } })
+    else return false
+    return true
+  }
+  return { preferences, normalized, customPresets, apply, savePreset }
+})
diff --git a/frontend/src/stores/theme.ts b/frontend/src/stores/theme.ts
index 536095e..f49bc3c 100644
--- a/frontend/src/stores/theme.ts
+++ b/frontend/src/stores/theme.ts
@@ -1,13 +1,14 @@
 import { defineStore } from 'pinia'
+import { useHeadingAppearanceStore } from './headingAppearance'
 import { ref, computed, watch } from 'vue'
 import type { ThemeConfig, ThemeManifest, InstalledTheme, ThemePackageInspection } from '@/contracts'
 import * as themePkg from '@/services/themePackageService'
 import { t } from '@/i18n'
 
 const builtinThemes = (): ThemeConfig[] => [
-  { theme_id: 'light', name: t('浅色', 'Light'), version: '1.2.0', description: t('默认浅色主题', 'Default light theme'), is_dark: false, builtin: true, code_theme: 'github-light' },
-  { theme_id: 'dark', name: t('深色', 'Dark'), version: '1.2.0', description: t('默认深色主题', 'Default dark theme'), is_dark: true, builtin: true, code_theme: 'github-dark' },
-  { theme_id: 'sepia', name: t('护眼', 'Sepia'), version: '1.2.0', description: t('护眼暖色调', 'Warm, low-glare theme'), is_dark: false, builtin: true, code_theme: 'github-light' },
+  { theme_id: 'light', name: t('浅色', 'Light'), version: '1.3.0', description: t('默认浅色主题', 'Default light theme'), is_dark: false, builtin: true, code_theme: 'github-light' },
+  { theme_id: 'dark', name: t('深色', 'Dark'), version: '1.3.0', description: t('默认深色主题', 'Default dark theme'), is_dark: true, builtin: true, code_theme: 'github-dark' },
+  { theme_id: 'sepia', name: t('护眼', 'Sepia'), version: '1.3.0', description: t('护眼暖色调', 'Warm, low-glare theme'), is_dark: false, builtin: true, code_theme: 'github-light' },
 ]
 
 export type CodeBlockThemePreference = 'auto' | 'github-light' | 'github-dark'
@@ -158,6 +159,7 @@ export const useThemeStore = defineStore('theme', () => {
   }
 
   function resetToDefault() {
+    useHeadingAppearanceStore().reset()
     applyTheme('light')
     fontEditorSize.value = 15
     fontEditorFamily.value = 'system-ui'
diff --git a/frontend/src/stores/workspace.ts b/frontend/src/stores/workspace.ts
index bd64a1d..fe37e96 100644
--- a/frontend/src/stores/workspace.ts
+++ b/frontend/src/stores/workspace.ts
@@ -13,6 +13,8 @@ export const useWorkspaceStore = defineStore('workspace', () => {
   const isLoading = ref(false)
   const hasVault = ref(false)
   const recentVaults = ref<workspaceService.VaultInfo[]>([])
+  const treeRefreshError = ref<string | null>(null)
+  let refreshSequence = 0
 
   const activeFile = computed(() => {
     if (!activeFilePath.value) return null
@@ -65,10 +67,27 @@ export const useWorkspaceStore = defineStore('workspace', () => {
   /** 重新拉取文件树。插件命令返回 refresh:workspace 时需要。 */
   async function refreshFileTree() {
     if (!hasVault.value) return
-    fileTree.value = await workspaceService.getFileTree()
+    const sequence = ++refreshSequence
+    const path = vaultPath.value
+    try {
+      const fresh = await workspaceService.refreshTree()
+      if (sequence !== refreshSequence || path !== vaultPath.value || !hasVault.value) return
+      const open = new Map<string, boolean>()
+      const collect = (nodes: FileNode[]) => nodes.forEach(node => { if (node.type === 'folder') open.set(node.path, !!node.is_open); if (node.children) collect(node.children) })
+      collect(fileTree.value)
+      const restore = (nodes: FileNode[]) => nodes.forEach(node => { if (node.type === 'folder') node.is_open = open.get(node.path) ?? false; if (node.children) restore(node.children) })
+      restore(fresh)
+      // Avoid redrawing an unchanged tree on every background check.
+      if (JSON.stringify(fresh) !== JSON.stringify(fileTree.value)) fileTree.value = fresh
+      treeRefreshError.value = null
+    } catch (error) {
+      if (sequence === refreshSequence) treeRefreshError.value = error instanceof Error ? error.message : '文件树刷新失败'
+      throw error
+    }
   }
 
   async function openVault(path: string) {
+    refreshSequence++
     isLoading.value = true
     try {
       const info = await workspaceService.openVault(path)
@@ -84,6 +103,7 @@ export const useWorkspaceStore = defineStore('workspace', () => {
   }
 
   async function createVault(path: string, name: string) {
+    refreshSequence++
     isLoading.value = true
     try {
       const info = await workspaceService.createVault(path, name)
@@ -162,6 +182,7 @@ export const useWorkspaceStore = defineStore('workspace', () => {
     isLoading,
     hasVault,
     recentVaults,
+    treeRefreshError,
     toggleFolder,
     openFile,
     closeFile,
diff --git a/frontend/src/stores/workspaceRefresh.spec.ts b/frontend/src/stores/workspaceRefresh.spec.ts
new file mode 100644
index 0000000..3634f97
--- /dev/null
+++ b/frontend/src/stores/workspaceRefresh.spec.ts
@@ -0,0 +1,20 @@
+// @vitest-environment happy-dom
+import { beforeEach, expect, it, vi } from 'vitest'
+import { createPinia, setActivePinia } from 'pinia'
+import { useWorkspaceStore } from './workspace'
+import * as service from '@/services/workspaceService'
+beforeEach(() => { setActivePinia(createPinia()); vi.restoreAllMocks() })
+it('fetches external entries while keeping folder state and ignoring stale responses', async () => {
+  const store = useWorkspaceStore()
+  store.hasVault = true; store.vaultPath = '/vault'
+  store.fileTree = [{ id: 'folder', path: '/folder', name: 'folder', type: 'folder', is_open: true, children: [] }]
+  let release!: (value: typeof store.fileTree) => void
+  vi.spyOn(service, 'refreshTree').mockImplementationOnce(() => new Promise(resolve => { release = resolve }))
+    .mockResolvedValueOnce([{ id: 'folder', path: '/folder', name: 'folder', type: 'folder', children: [{ id: 'new', path: '/folder/new.md', name: 'new.md', type: 'file' }] }])
+  const old = store.refreshFileTree()
+  await store.refreshFileTree()
+  expect(store.fileTree[0]!.is_open).toBe(true)
+  expect(store.fileTree[0]!.children).toHaveLength(1)
+  release([]); await old
+  expect(store.fileTree).toHaveLength(1)
+})
diff --git a/frontend/src/styles/headings.css b/frontend/src/styles/headings.css
new file mode 100644
index 0000000..6cee751
--- /dev/null
+++ b/frontend/src/styles/headings.css
@@ -0,0 +1,19 @@
+.heading-fold-hidden { display: none !important; }
+.milkdown .ProseMirror .heading-fold-toggle { opacity: 0; pointer-events: none; transition: opacity 120ms ease; }
+.milkdown .ProseMirror :is(h1,h2,h3,h4,h5,h6):hover > .heading-fold-toggle,
+.milkdown .ProseMirror .heading-fold-toggle:focus-visible { opacity: 1; pointer-events: auto; }
+@media (hover: none) { .milkdown .ProseMirror .heading-fold-toggle { opacity: 1; pointer-events: auto; } }
+@media (prefers-reduced-motion: reduce) { .milkdown .ProseMirror .heading-fold-toggle { transition: none; } }
+.milkdown .ProseMirror .heading-fold-toggle { display: inline-flex; align-items: center; justify-content: center; vertical-align: middle; width: 24px; height: 28px; padding: 0; margin-inline-end: 5px; border: 0; border-radius: var(--radius-sm); background: transparent; color: var(--color-text-secondary); font: 16px/1 system-ui; cursor: pointer; user-select: none; }
+.milkdown .ProseMirror .heading-fold-toggle:hover { background: var(--color-background-hover); color: var(--color-accent-primary); }
+.milkdown .ProseMirror .heading-fold-toggle:focus-visible { outline: 2px solid var(--color-border-focus); outline-offset: 2px; }
+[data-heading-style='custom'] :is(.ProseMirror, .markdown-content) :is(h1,h2,h3,h4,h5,h6) { font-family: var(--heading-family) !important; }
+[data-heading-style='custom'] :is(.ProseMirror, .markdown-content) h1 { font-size: var(--heading-1-size) !important; font-weight: var(--heading-1-weight) !important; }
+[data-heading-style='custom'] :is(.ProseMirror, .markdown-content) h2 { font-size: var(--heading-2-size) !important; font-weight: var(--heading-2-weight) !important; }
+[data-heading-style='custom'] :is(.ProseMirror, .markdown-content) h3 { font-size: var(--heading-3-size) !important; font-weight: var(--heading-3-weight) !important; }
+[data-heading-style='custom'] :is(.ProseMirror, .markdown-content) h4 { font-size: var(--heading-4-size) !important; font-weight: var(--heading-4-weight) !important; }
+[data-heading-style='custom'] :is(.ProseMirror, .markdown-content) h5 { font-size: var(--heading-5-size) !important; font-weight: var(--heading-5-weight) !important; }
+[data-heading-style='custom'] :is(.ProseMirror, .markdown-content) h6 { font-size: var(--heading-6-size) !important; font-weight: var(--heading-6-weight) !important; }
+
+.milkdown .ProseMirror .heading-fold-toggle::before { content: ''; width: 6px; height: 6px; border-right: 1.5px solid currentColor; border-bottom: 1.5px solid currentColor; transform: rotate(45deg); }
+.milkdown .ProseMirror .heading-fold-toggle[aria-expanded='false']::before { transform: rotate(-45deg); }
diff --git a/frontend/src/utils/callouts.spec.ts b/frontend/src/utils/callouts.spec.ts
index 5662b5c..dea7aab 100644
--- a/frontend/src/utils/callouts.spec.ts
+++ b/frontend/src/utils/callouts.spec.ts
@@ -2,8 +2,22 @@
 import { describe, expect, it } from 'vitest'
 import { calloutTypes, parseCallout } from './callouts'
 import { renderMarkdown } from './markdown'
+import { defaultMarkdownPreferences } from '@/stores/markdownPreferences'
 
 describe('callouts', () => {
+  it('keeps disabled syntax literal without leaking settings between render requests', async () => {
+    const source = '> [!WARNING]\n> text\n\n$x$\n\nhttps://example.com'
+    const [plain, extended] = await Promise.all([
+      renderMarkdown(source, { preferences: { ...defaultMarkdownPreferences, callouts: false, math: false, autoLinks: false } }),
+      renderMarkdown(source),
+    ])
+    expect(plain).not.toContain('markdown-callout')
+    expect(plain).not.toContain('katex')
+    expect(plain).not.toContain('<a ')
+    expect(extended).toContain('markdown-callout')
+    expect(extended).toContain('katex')
+    expect(extended).toContain('<a ')
+  })
   for (const [type, aliases] of Object.entries(calloutTypes)) {
     for (const alias of aliases) it(`renders ${alias}`, async () => {
       const root = document.createElement('div')
diff --git a/frontend/src/utils/markdown.ts b/frontend/src/utils/markdown.ts
index 289de90..9320159 100644
--- a/frontend/src/utils/markdown.ts
+++ b/frontend/src/utils/markdown.ts
@@ -1,5 +1,6 @@
 import DOMPurify from 'dompurify'
-import { marked } from 'marked'
+import { Marked } from 'marked'
+import { defaultMarkdownPreferences, type MarkdownPreferences } from '@/stores/markdownPreferences'
 import { createHighlighterCore } from 'shiki/core'
 import { createOnigurumaEngine } from 'shiki/engine/oniguruma'
 import { bundledLanguagesInfo } from 'shiki/langs'
@@ -12,7 +13,16 @@ import 'katex/dist/katex.min.css'
 import { parseCallout, escapeCalloutTitle } from './callouts'
 import '@/styles/callouts.css'
 
+function mathHtml(source: string, displayMode: boolean) {
+  const result = katex.renderToString(source, {displayMode, throwOnError:false, trust:false, maxExpand:1000, output:'html'})
+  const label = source.replace(/&/g, '&amp;').replace(/"/g, '&quot;').replace(/</g, '&lt;')
+  return `<${displayMode ? 'div' : 'span'} class="markdown-math" role="math" aria-label="${label}">${result}</${displayMode ? 'div' : 'span'}>`
+}
+
+function createMarkdownParser(preferences: MarkdownPreferences) {
+const marked = new Marked()
 marked.use({ renderer: { blockquote(token) {
+  if (!preferences.callouts) return false
   const callout = parseCallout(token.text)
   if (!callout) return false
   const title = escapeCalloutTitle(callout.title)
@@ -23,13 +33,7 @@ marked.use({ renderer: { blockquote(token) {
     : `<aside ${attributes}><div class="callout-title">${title}</div><div class="callout-body">${body}</div></aside>`
 } } })
 
-function mathHtml(source: string, displayMode: boolean) {
-  const result = katex.renderToString(source, {displayMode, throwOnError:false, trust:false, maxExpand:1000, output:'html'})
-  const label = source.replace(/&/g, '&amp;').replace(/"/g, '&quot;').replace(/</g, '&lt;')
-  return `<${displayMode ? 'div' : 'span'} class="markdown-math" role="math" aria-label="${label}">${result}</${displayMode ? 'div' : 'span'}>`
-}
-
-marked.use({extensions:[
+if (preferences.math) marked.use({extensions:[
   {name:'blockMath',level:'block',tokenizer(source) {
     const match = /^ {0,3}\$\$\s*\n?([\s\S]+?)\n?\$\$[ \t]*(?:\n|$)/.exec(source)
     if (match) return {type:'blockMath',raw:match[0],text:match[1]!.trim()}
@@ -43,6 +47,9 @@ marked.use({extensions:[
 ]})
 
 marked.setOptions({ gfm: true, breaks: true })
+if (!preferences.autoLinks) marked.use({ tokenizer: { url() { return undefined } } })
+return marked
+}
 
 // Highlighter 是昂贵的单例；复用初始化 Promise，避免每个代码块重复加载语法与主题。
 let highlighter: ReturnType<typeof createHighlighterCore> | undefined
@@ -95,7 +102,9 @@ export async function getCodeTokenizer(theme: 'github-light' | 'github-dark', re
   }
 }
 
-export async function renderMarkdown(source: string, options?: { theme?: 'light' | 'dark' }): Promise<string> {
+export async function renderMarkdown(source: string, options?: { theme?: 'light' | 'dark'; preferences?: MarkdownPreferences }): Promise<string> {
+  const preferences = options?.preferences ?? defaultMarkdownPreferences
+  const marked = createMarkdownParser(preferences)
   const html = marked.parse(source, { async: false }) as string
   const documentNode = new DOMParser().parseFromString(`<body>${html}</body>`, 'text/html')
 
@@ -103,11 +112,11 @@ export async function renderMarkdown(source: string, options?: { theme?: 'light'
 
   for (const code of documentNode.querySelectorAll('pre > code')) {
     const requestedLanguage = [...code.classList].find((name) => name.startsWith('language-'))?.slice(9) || 'text'
-    if (requestedLanguage === 'mermaid') {
+    if (requestedLanguage === 'mermaid' && preferences.diagrams) {
       mermaidBlocks.push({ pre: code.parentElement!, source: code.textContent ?? '' })
       continue
     }
-    if (requestedLanguage.toLowerCase() === 'latex') {
+    if (requestedLanguage.toLowerCase() === 'latex' && preferences.math) {
       code.parentElement?.replaceWith(document.createRange().createContextualFragment(mathHtml(code.textContent ?? '', true)))
       continue
     }