diff --git a/frontend/src/assets/themes/paper-moments.theme b/frontend/src/assets/themes/paper-moments.theme
index 42ebc3a..f92ee31 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: 1.4.0
+version: 1.4.1
 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
@@ -141,7 +141,7 @@ license: MIT
 [data-theme="paper-moments"] .markdown-toolbar { background: #fff9e9; border-bottom: 1px dashed #b5a693; }
 [data-theme="paper-moments"] .milkdown-host { padding: 30px 24px 40px; }
 [data-theme="paper-moments"] .milkdown-host .milkdown { background: transparent; }
-[data-theme="paper-moments"] .milkdown-host .ProseMirror {
+[data-theme="paper-moments"] .visual-editor .milkdown-host .ProseMirror {
   width: 90%;
   max-width: none;
   position: relative;
@@ -172,7 +172,7 @@ license: MIT
 [data-theme="paper-moments"] .editor-pane.source { margin: 20px; width: calc(100% - 40px); border: 1px solid #b5a693; border-radius: 8px; background: #fffef8; box-shadow: var(--shadow-md); }
 @media (max-width: 720px) {
   [data-theme="paper-moments"] .milkdown-host { padding: 20px 12px 28px; }
-  [data-theme="paper-moments"] .milkdown-host .ProseMirror { width: 100%; padding: 30px 18px 40px 38px; }
+  [data-theme="paper-moments"] .visual-editor .milkdown-host .ProseMirror { width: 100%; padding: 30px 18px 40px 38px; }
 }
 
 /* Warm neutral surfaces preserve the contrast of the selected Shiki palette. */
diff --git a/frontend/src/components/common/MarkdownContent.vue b/frontend/src/components/common/MarkdownContent.vue
index 5fc08ac..dd11226 100644
--- a/frontend/src/components/common/MarkdownContent.vue
+++ b/frontend/src/components/common/MarkdownContent.vue
@@ -11,11 +11,11 @@ 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], async ([source, theme]) => {
+watch([() => props.source, diagramTheme, () => themeStore.currentThemeId], async ([source, theme]) => {
   const version = ++renderVersion
   const result = await renderMarkdown(source, { theme })
   if (version === renderVersion) html.value = result
-}, { immediate: true })
+}, { immediate: true, flush: 'post' })
 </script>
 
 <template>
diff --git a/frontend/src/components/common/MermaidBlock.vue b/frontend/src/components/common/MermaidBlock.vue
index 6ec0c96..e307081 100644
--- a/frontend/src/components/common/MermaidBlock.vue
+++ b/frontend/src/components/common/MermaidBlock.vue
@@ -13,7 +13,7 @@ const emit = defineEmits<{
   (e: 'rendered', info: { width: number; height: number }): void
 }>()
 
-const { mermaidTheme } = useMermaidTheme()
+const { mermaidTheme, themeId } = useMermaidTheme()
 const svgHtml = ref('')
 const isLoading = ref(true)
 const hasError = ref(false)
@@ -52,7 +52,7 @@ async function doRender() {
 
 onMounted(doRender)
 
-watch(() => [props.source, mermaidTheme.value], () => { scale.value = 1; doRender() })
+watch(() => [props.source, mermaidTheme.value, themeId.value], () => { scale.value = 1; doRender() }, { flush: 'post' })
 
 function zoomIn() { scale.value = Math.min(scale.value * 1.2, 5) }
 function zoomOut() { scale.value = Math.max(scale.value / 1.2, 0.2) }
diff --git a/frontend/src/components/common/SecondarySidebar.spec.ts b/frontend/src/components/common/SecondarySidebar.spec.ts
new file mode 100644
index 0000000..a9f7091
--- /dev/null
+++ b/frontend/src/components/common/SecondarySidebar.spec.ts
@@ -0,0 +1,23 @@
+// @vitest-environment happy-dom
+import { expect, it } from 'vitest'
+import { mount } from '@vue/test-utils'
+import { createRouter, createMemoryHistory } from 'vue-router'
+import SecondarySidebar from './SecondarySidebar.vue'
+
+it('resizes by keyboard, clamps bounds and restores the saved width', async () => {
+  localStorage.removeItem('workspace-sidebar-width')
+  const router = createRouter({ history: createMemoryHistory(), routes: [{ path: '/', component: { template: '<div />' } }] })
+  await router.push('/')
+  const options = { props: { component: 'file-tree' }, global: { plugins: [router], stubs: { FileTreePanel: true } } }
+  let wrapper = mount(SecondarySidebar, options)
+  await wrapper.get('[role="separator"]').trigger('keydown', { key: 'ArrowRight' })
+  expect(localStorage.getItem('workspace-sidebar-width')).toBe('288')
+  wrapper.unmount()
+  wrapper = mount(SecondarySidebar, options)
+  await wrapper.vm.$nextTick()
+  expect(wrapper.get('aside').attributes('style')).toContain('288px')
+  await wrapper.get('[role="separator"]').trigger('keydown', { key: 'Home' })
+  expect(wrapper.get('aside').attributes('style')).toContain('200px')
+  wrapper.unmount()
+  localStorage.removeItem('workspace-sidebar-width')
+})
diff --git a/frontend/src/components/common/SecondarySidebar.vue b/frontend/src/components/common/SecondarySidebar.vue
index 9f11c96..0a2440c 100644
--- a/frontend/src/components/common/SecondarySidebar.vue
+++ b/frontend/src/components/common/SecondarySidebar.vue
@@ -1,5 +1,5 @@
 <script setup lang="ts">
-import { computed } from 'vue'
+import { computed, onBeforeUnmount, onMounted, ref } from 'vue'
 import FileTreePanel from '@/features/workspace/FileTreePanel.vue'
 import ConversationListPanel from '@/features/chat/ConversationListPanel.vue'
 import RunListPanel from '@/features/agent/RunListPanel.vue'
@@ -15,6 +15,40 @@ const props = defineProps<{
 
 const route = useRoute()
 const routeName = computed(() => route.name as string)
+const sidebar = ref<HTMLElement | null>(null)
+const width = ref(272)
+const maxWidth = ref(520)
+let dragging = false
+function saveWidth() { try { localStorage.setItem('workspace-sidebar-width', String(width.value)) } catch { /* Keep resizing available when storage is unavailable. */ } }
+function clampWidth(value: number) { return Math.max(200, Math.min(maxWidth.value, value)) }
+function updateBounds() {
+  maxWidth.value = Math.max(200, Math.min(520, window.innerWidth - (sidebar.value?.getBoundingClientRect().left ?? 0) - 320))
+  width.value = clampWidth(width.value)
+}
+function beginResize(event: PointerEvent) {
+  if (event.button !== 0) return
+  event.preventDefault()
+  updateBounds()
+  dragging = true
+  ;(event.currentTarget as HTMLElement).setPointerCapture(event.pointerId)
+}
+function resize(event: PointerEvent) {
+  if (dragging) width.value = clampWidth(event.clientX - (sidebar.value?.getBoundingClientRect().left ?? 0))
+}
+function endResize() { if (dragging) { dragging = false; saveWidth() } }
+function resizeWithKeyboard(event: KeyboardEvent) {
+  if (!['ArrowLeft', 'ArrowRight', 'Home', 'End'].includes(event.key)) return
+  event.preventDefault()
+  updateBounds()
+  width.value = event.key === 'Home' ? 200 : event.key === 'End' ? maxWidth.value : clampWidth(width.value + (event.key === 'ArrowLeft' ? -16 : 16))
+  saveWidth()
+}
+onMounted(() => {
+  try { const saved = Number(localStorage.getItem('workspace-sidebar-width')); if (saved >= 200 && Number.isFinite(saved)) width.value = saved } catch { /* Use default width. */ }
+  updateBounds()
+  window.addEventListener('resize', updateBounds)
+})
+onBeforeUnmount(() => { endResize(); window.removeEventListener('resize', updateBounds) })
 
 const sidebarTitle = computed(() => {
   const titles: Record<string, string> = {
@@ -32,7 +66,7 @@ const showSkillToggle = computed(() => routeName.value === 'skills' || routeName
 </script>
 
 <template>
-  <aside class="secondary-sidebar">
+  <aside ref="sidebar" class="secondary-sidebar" :style="component === 'file-tree' ? { width: `${width}px` } : undefined">
     <div v-if="component !== 'file-tree'" class="sidebar-header">
       <h3 class="sidebar-title">{{ sidebarTitle }}</h3>
       <div v-if="showSkillToggle" class="sidebar-tabs">
@@ -48,11 +82,13 @@ const showSkillToggle = computed(() => routeName.value === 'skills' || routeName
       <TaskFiltersPanel v-else-if="component === 'task-filters'" />
       <ExtensionListPanel v-else-if="component === 'extension-list'" />
     </div>
+    <div v-if="component === 'file-tree'" class="sidebar-resizer" role="separator" aria-orientation="vertical" :aria-label="t('调整文件侧栏宽度', 'Resize file sidebar')" :aria-valuenow="width" :aria-valuemin="200" :aria-valuemax="maxWidth" tabindex="0" @pointerdown="beginResize" @pointermove="resize" @pointerup="endResize" @pointercancel="endResize" @lostpointercapture="endResize" @keydown="resizeWithKeyboard" @dblclick="width = clampWidth(272); saveWidth()" />
   </aside>
 </template>
 
 <style scoped>
 .secondary-sidebar {
+  position: relative;
   width: var(--sidebar-secondary-width);
   background: var(--color-surface-secondary);
   border-right: 1px solid var(--color-border-default);
@@ -111,6 +147,8 @@ const showSkillToggle = computed(() => routeName.value === 'skills' || routeName
   overflow-x: hidden;
   scrollbar-gutter: stable;
 }
+.sidebar-resizer { position: absolute; top: 0; bottom: 0; right: -3px; width: 6px; z-index: 20; cursor: col-resize; touch-action: none; }
+.sidebar-resizer:hover, .sidebar-resizer:focus-visible { background: var(--color-accent-secondary); outline: none; }
 .file-sidebar-content { min-height: 0; overflow: hidden; scrollbar-gutter: auto; }
 
 </style>
diff --git a/frontend/src/features/editor/VisualMarkdownEditor.vue b/frontend/src/features/editor/VisualMarkdownEditor.vue
index 58323fd..23e61e0 100644
--- a/frontend/src/features/editor/VisualMarkdownEditor.vue
+++ b/frontend/src/features/editor/VisualMarkdownEditor.vue
@@ -62,6 +62,22 @@ const fontSizeInput = ref(16)
 let crepe: Crepe | null = null
 let disposeLanguagePicker: (() => void) | undefined
 let disposeCodeLabels: (() => void) | undefined
+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) {
+    if (entry.apply === apply) diagramPreviews.delete(id)
+  }
+  const element = createMermaidPreview(source, themeStore.isDark, apply)
+  diagramPreviews.set(element.id, { source, apply })
+  return element
+}
+watch(() => themeStore.currentThemeId, () => {
+  const current = [...diagramPreviews.entries()]
+  diagramPreviews.clear()
+  for (const [id, entry] of current) {
+    if (editorRoot.value?.querySelector(`[id="${id}"]`)) entry.apply(renderDiagram(entry.source, entry.apply))
+  }
+}, { flush: 'post' })
 
 function applyProofingPreferences() {
   const editable = editorRoot.value?.querySelector<HTMLElement>('.ProseMirror')
@@ -206,7 +222,7 @@ onMounted(async () => {
     languages: shikiLanguages(themeStore.resolvedCodeBlockTheme),
     renderLanguage: renderCodeLanguage,
     renderPreview: (language, content, applyPreview) => language.trim().toLowerCase() === 'mermaid'
-      ? createMermaidPreview(content, themeStore.isDark, applyPreview)
+      ? renderDiagram(content, applyPreview)
       : config.renderPreview(language, content, applyPreview),
     extensions: [basicSetup, keymap.of([indentWithTab]), shikiEditorTheme(themeStore.resolvedCodeBlockTheme)],
   })))
@@ -242,7 +258,7 @@ watch(() => editorStore.headingRequest, request => {
   })
 })
 
-onBeforeUnmount(() => { disposeCodeLabels?.(); disposeLanguagePicker?.(); void crepe?.destroy() })
+onBeforeUnmount(() => { diagramPreviews.clear(); disposeCodeLabels?.(); disposeLanguagePicker?.(); void crepe?.destroy() })
 
 defineExpose({ getEditor: () => crepe?.editor })
 </script>
diff --git a/frontend/src/features/workspace/FileTreePanel.spec.ts b/frontend/src/features/workspace/FileTreePanel.spec.ts
index c532221..24b1675 100644
--- a/frontend/src/features/workspace/FileTreePanel.spec.ts
+++ b/frontend/src/features/workspace/FileTreePanel.spec.ts
@@ -48,6 +48,16 @@ afterEach(() => {
 })
 
 describe('FileTreePanel file switching', () => {
+  it('expands every nested folder from the toolbar', async () => {
+    const router = createRouter({ history: createMemoryHistory(), routes: [{ path: '/workspace', component: { template: '<div />' } }] })
+    await router.push('/workspace')
+    const store = useWorkspaceStore()
+    store.fileTree = [{ id: 'a', name: 'A', path: '/a', type: 'folder', is_open: false, children: [{ id: 'b', name: 'B', path: '/a/b', type: 'folder', is_open: false }] }]
+    wrapper = mount(FileTreePanel, { global: { plugins: [router] } })
+    await wrapper.get('[aria-label="全部展开文件夹"]').trigger('click')
+    expect(store.fileTree[0]!.is_open).toBe(true)
+    expect(store.fileTree[0]!.children![0]!.is_open).toBe(true)
+  })
   it('switches full-height panels using tabs and preserves the file search', async () => {
     const router = createRouter({ history: createMemoryHistory(), routes: [{ path: '/workspace', component: { template: '<div />' } }] })
     await router.push('/workspace')
diff --git a/frontend/src/features/workspace/FileTreePanel.vue b/frontend/src/features/workspace/FileTreePanel.vue
index 35fc624..59da5d1 100644
--- a/frontend/src/features/workspace/FileTreePanel.vue
+++ b/frontend/src/features/workspace/FileTreePanel.vue
@@ -68,6 +68,12 @@ const filteredTree = computed(() => {
   })
   return filter(workspaceStore.fileTree)
 })
+function expandAllFiles() {
+  const expand = (nodes: FileNode[]) => nodes.forEach(node => {
+    if (node.type === 'folder') { node.is_open = true; expand(node.children ?? []) }
+  })
+  expand(workspaceStore.fileTree)
+}
 let lastScrollTop = 0
 function revealSearch(event: WheelEvent) {
   if (activeTab.value !== 'files') return
@@ -216,6 +222,7 @@ function containingFolder(path: string): string {
       <button type="button" :title="t('新建笔记', 'New note')" :aria-label="t('新建笔记', 'New note')" @click.stop="beginCreate('file', selectedFolderPath)"><AppIcon :icon="DocumentAdd" /></button>
       <button type="button" :title="t('新建文件夹', 'New folder')" :aria-label="t('新建文件夹', 'New folder')" @click.stop="beginCreate('folder', selectedFolderPath)"><AppIcon :icon="FolderAdd" /></button>
       <button type="button" :aria-label="t('搜索文件', 'Search files')" :aria-expanded="searchVisible" @click="searchVisible = !searchVisible">{{ t('搜索', 'Search') }}</button>
+      <button type="button" :aria-label="t('全部展开文件夹', 'Expand all folders')" @click="expandAllFiles">{{ t('全部展开', 'Expand all') }}</button>
     </div>
     <div v-if="searchVisible || searchQuery || searchFocused" class="file-search">
       <input v-model="searchQuery" type="search" :placeholder="t('搜索文件或文件夹…', 'Search files or folders…')" :aria-label="t('搜索文件或文件夹', 'Search files or folders')" @focus="searchFocused = true" @blur="searchFocused = false" />
diff --git a/frontend/src/services/mermaidService.ts b/frontend/src/services/mermaidService.ts
index 5e09de3..57eb899 100644
--- a/frontend/src/services/mermaidService.ts
+++ b/frontend/src/services/mermaidService.ts
@@ -1,31 +1,45 @@
 import mermaid from 'mermaid'
-import { ref, watch } from 'vue'
+import { computed } from 'vue'
 import { useThemeStore } from '@/stores/theme'
 
-let initialized = false
-let initTheme: 'light' | 'dark' = 'light'
+export function mermaidThemeVariables(dark: boolean) {
+  const style = typeof document === 'undefined' ? null : getComputedStyle(document.documentElement)
+  const color = (name: string, fallback: string) => style?.getPropertyValue(`--color-${name}`).trim() || fallback
+  const text = color('text-primary', dark ? '#e6edf3' : '#1f2328')
+  const border = color('border-default', dark ? '#484f58' : '#d0d7de')
+  const surface = color('surface-primary', dark ? '#161b22' : '#ffffff')
+  const primary = color('accent-soft', dark ? '#30363d' : '#eef0ff')
+  const line = color('text-secondary', dark ? '#b1bac4' : '#656d76')
+  return {
+    darkMode: dark, background: surface, primaryColor: primary, primaryTextColor: text, primaryBorderColor: border,
+    secondaryColor: color('info-soft', primary), secondaryTextColor: text, secondaryBorderColor: border,
+    tertiaryColor: color('success-soft', primary), tertiaryTextColor: text, tertiaryBorderColor: border,
+    textColor: text, lineColor: line, mainBkg: primary, nodeBorder: border,
+    clusterBkg: surface, clusterBorder: border, edgeLabelBackground: surface,
+    actorBkg: primary, actorBorder: border, actorTextColor: text, actorLineColor: line,
+    signalColor: line, signalTextColor: text, labelBoxBkgColor: surface, labelBoxBorderColor: border, labelTextColor: text,
+    noteBkgColor: color('warning-soft', primary), noteTextColor: text, noteBorderColor: border,
+    activationBkgColor: primary, activationBorderColor: border,
+  }
+}
 
 function ensureInitialized(theme: 'light' | 'dark') {
-  if (!initialized) {
     mermaid.initialize({
       startOnLoad: false,
-      theme: theme === 'dark' ? 'dark' : 'default',
+      theme: 'base',
+      themeVariables: mermaidThemeVariables(theme === 'dark'),
       securityLevel: 'strict',
       fontFamily: 'var(--font-ui-sans)',
       flowchart: { useMaxWidth: true, htmlLabels: true },
       sequence: { useMaxWidth: true },
       gantt: { useMaxWidth: true },
     })
-    initialized = true
-    initTheme = theme
-    return
-  }
-  if (initTheme !== theme) {
-    mermaid.initialize({
-      theme: theme === 'dark' ? 'dark' : 'default',
-    })
-    initTheme = theme
-  }
+}
+let queue: Promise<unknown> = Promise.resolve()
+function serialized<T>(work: () => Promise<T>): Promise<T> {
+  const result = queue.then(work)
+  queue = result.catch(() => {})
+  return result
 }
 
 export interface MermaidRenderResult {
@@ -43,7 +57,11 @@ export interface MermaidParseError {
 
 let renderCounter = 0
 
-export async function renderMermaid(
+export function renderMermaid(source: string, options: { theme?: 'light' | 'dark'; mode?: 'interactive' | 'static' } = {}): Promise<MermaidRenderResult> {
+  return serialized(() => renderMermaidNow(source, options))
+}
+
+async function renderMermaidNow(
   source: string,
   options: { theme?: 'light' | 'dark'; mode?: 'interactive' | 'static' } = {}
 ): Promise<MermaidRenderResult> {
@@ -106,18 +124,14 @@ function escapeXml(str: string): string {
 
 export function useMermaidTheme() {
   const themeStore = useThemeStore()
-  const mermaidTheme = ref<'light' | 'dark'>(themeStore.isDark ? 'dark' : 'light')
-  watch(() => themeStore.isDark, (isDark) => {
-    mermaidTheme.value = isDark ? 'dark' : 'light'
-    ensureInitialized(mermaidTheme.value)
-  })
-  return { mermaidTheme }
+  const mermaidTheme = computed<'light' | 'dark'>(() => themeStore.isDark ? 'dark' : 'light')
+  const themeId = computed(() => themeStore.currentThemeId)
+  return { mermaidTheme, themeId }
 }
 
 export async function validateMermaid(source: string): Promise<{ valid: boolean; error?: MermaidParseError }> {
   try {
-    ensureInitialized('light')
-    await mermaid.parse(source)
+    await serialized(async () => { ensureInitialized('light'); await mermaid.parse(source) })
     return { valid: true }
   } catch (error) {
     const message = error instanceof Error ? error.message : '未知错误'
diff --git a/frontend/src/services/mermaidTheme.spec.ts b/frontend/src/services/mermaidTheme.spec.ts
new file mode 100644
index 0000000..7eabfc9
--- /dev/null
+++ b/frontend/src/services/mermaidTheme.spec.ts
@@ -0,0 +1,22 @@
+// @vitest-environment happy-dom
+import { afterEach, expect, it, vi } from 'vitest'
+import mermaid from 'mermaid'
+import { mermaidThemeVariables, renderMermaid } from './mermaidService'
+
+vi.mock('mermaid', () => ({ default: { initialize: vi.fn(), render: vi.fn().mockResolvedValue({ svg: '<svg viewBox="0 0 10 10"></svg>' }) } }))
+afterEach(() => { document.documentElement.removeAttribute('style'); vi.clearAllMocks() })
+it('uses the current theme tokens for nodes, actors, text and lines', () => {
+  document.documentElement.style.setProperty('--color-accent-soft', '#f3e1d8')
+  document.documentElement.style.setProperty('--color-text-primary', '#493f35')
+  const theme = mermaidThemeVariables(false)
+  expect(theme.primaryColor).toBe('#f3e1d8')
+  expect(theme.actorBkg).toBe('#f3e1d8')
+  expect(theme.primaryTextColor).toBe('#493f35')
+  expect(theme.actorTextColor).toBe('#493f35')
+})
+it('keeps explicit diagram styling and initializes base palette on each render', async () => {
+  const source = 'graph TD; A-->B; style A fill:#f9f'
+  await renderMermaid(source)
+  expect(mermaid.initialize).toHaveBeenCalledWith(expect.objectContaining({ theme: 'base', securityLevel: 'strict', themeVariables: expect.any(Object) }))
+  expect(mermaid.render).toHaveBeenCalledWith(expect.any(String), source)
+})