diff --git a/prisma/dev.db b/prisma/dev.db
index 527797c..b4c7051 100644
Binary files a/prisma/dev.db and b/prisma/dev.db differ
diff --git a/src/app/api/pages/[id]/route.ts b/src/app/api/pages/[id]/route.ts
index 32b895f..1fe7cc4 100644
--- a/src/app/api/pages/[id]/route.ts
+++ b/src/app/api/pages/[id]/route.ts
@@ -113,10 +113,10 @@ export async function PUT(
                 return NextResponse.json({ error: 'Invalid title' }, { status: 400 });
             }
             const trimmed = body.title.trim();
-            if (!trimmed || trimmed.length > MAX_TITLE_LENGTH) {
+            if (trimmed.length > MAX_TITLE_LENGTH) {
                 return NextResponse.json({ error: 'Invalid title' }, { status: 400 });
             }
-            updateData.title = trimmed;
+            updateData.title = trimmed || '无标题';
         }
 
         if (body.content !== undefined) {
diff --git a/src/app/globals.css b/src/app/globals.css
index 67f0062..e7af1ed 100644
--- a/src/app/globals.css
+++ b/src/app/globals.css
@@ -1,4 +1,4 @@
-@import 'highlight.js/styles/atom-one-dark.css';
+@import 'highlight.js/styles/atom-one-dark.css';
 @tailwind base;
 @tailwind components;
 @tailwind utilities;
@@ -26,6 +26,7 @@
     --input: 35 15% 85%;
     --ring: 223 21% 30%;
     --radius: 0.75rem;
+    --code-bg: 220 16% 21%;
   }
 
   .dark {
@@ -57,6 +58,7 @@
     --border: 220 8% 28%;
     --input: 220 8% 28%;
     --ring: 210 16% 78%;
+    --code-bg: 220 16% 20%;
   }
 
   * {
@@ -76,7 +78,8 @@
 
 @layer components {
   .ui-card {
-    @apply rounded-2xl border border-border/70 bg-card/95 shadow-sm backdrop-blur-sm;
+    @apply rounded-xl border border-border/65 bg-card shadow-sm backdrop-blur-sm;
+    background-color: hsl(var(--card) / 0.92);
   }
 
   .ui-input {
@@ -88,23 +91,23 @@
   }
 
   .ui-btn {
-    @apply inline-flex items-center justify-center gap-2 rounded-xl px-4 py-2 text-sm font-medium transition-all active:scale-[0.98];
+    @apply inline-flex items-center justify-center gap-2 rounded-xl border border-transparent px-4 py-2 text-sm font-semibold transition-all active:scale-[0.98] disabled:cursor-not-allowed disabled:opacity-55 disabled:active:scale-100 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring/25;
   }
 
   .ui-btn-primary {
-    @apply ui-btn bg-primary text-primary-foreground hover:opacity-90 shadow-sm;
+    @apply ui-btn border-primary/20 bg-primary text-primary-foreground shadow-sm hover:opacity-90;
   }
 
   .ui-btn-secondary {
-    @apply ui-btn bg-secondary text-secondary-foreground hover:bg-secondary/80;
+    @apply ui-btn border-border/70 bg-secondary/85 text-secondary-foreground hover:bg-secondary;
   }
 
   .ui-btn-danger {
-    @apply ui-btn bg-destructive text-destructive-foreground hover:opacity-90;
+    @apply ui-btn border-destructive/25 bg-destructive text-destructive-foreground hover:opacity-90;
   }
 
   .ui-icon-btn {
-    @apply inline-flex h-9 w-9 items-center justify-center rounded-lg border border-transparent text-muted-foreground transition-colors hover:border-border hover:bg-muted/60 hover:text-foreground;
+    @apply inline-flex h-9 w-9 items-center justify-center rounded-lg border border-border/40 bg-background/30 text-muted-foreground transition-colors active:scale-[0.98] disabled:cursor-not-allowed disabled:opacity-55 disabled:active:scale-100 hover:border-border hover:bg-muted/60 hover:text-foreground focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring/25;
   }
 
   .ui-kbd {
@@ -159,11 +162,72 @@
 .ProseMirror {
   outline: none;
   min-height: 300px;
-  padding-bottom: 50px;
+  padding-bottom: 56px;
   font-size: 1.05rem;
   line-height: var(--editor-line-height, 1.5);
-  /* Use CSS variable with fallback */
-  /* Reduced from 1.75 */
+  letter-spacing: 0.003em;
+}
+
+@media (max-width: 768px) {
+  .ProseMirror {
+    font-size: 1rem;
+    line-height: max(1.55, var(--editor-line-height, 1.5));
+  }
+}
+
+.ProseMirror > * + * {
+  margin-top: 0.7em;
+}
+
+.ProseMirror h1,
+.ProseMirror h2,
+.ProseMirror h3 {
+  color: hsl(var(--foreground));
+  font-weight: 750;
+  line-height: 1.28;
+  letter-spacing: -0.01em;
+}
+
+.ProseMirror h1 {
+  margin-top: 1.2em;
+  font-size: clamp(1.7rem, 1.3rem + 1.3vw, 2.15rem);
+}
+
+.ProseMirror h2 {
+  margin-top: 1.05em;
+  font-size: clamp(1.35rem, 1.18rem + 0.8vw, 1.7rem);
+}
+
+.ProseMirror h3 {
+  margin-top: 0.9em;
+  font-size: clamp(1.12rem, 1.02rem + 0.45vw, 1.3rem);
+}
+
+.ProseMirror p {
+  color: hsl(var(--foreground));
+}
+
+.ProseMirror ul,
+.ProseMirror ol {
+  margin: 0.5em 0;
+  padding-left: 1.2em;
+}
+
+.ProseMirror li {
+  margin: 0.22em 0;
+}
+
+.ProseMirror a {
+  color: hsl(var(--primary));
+  text-decoration: underline;
+  text-decoration-thickness: 1px;
+  text-underline-offset: 2px;
+}
+
+.ProseMirror hr {
+  margin: 1.1em 0;
+  border: 0;
+  border-top: 1px solid hsl(var(--border));
 }
 
 .ProseMirror p.is-editor-empty:first-child::before {
@@ -176,20 +240,15 @@
 
 .ProseMirror blockquote {
   border-left: 3px solid hsl(var(--primary));
-  /* Make border color slightly more visible (primary) */
-  padding-left: 1rem;
+  padding-left: 0.95rem;
   color: hsl(var(--muted-foreground));
   font-family: "Georgia", "Cambria", "Times New Roman", serif !important;
-  /* Force serif font */
   font-style: italic;
-  margin: 1rem 0;
+  margin: 0.95rem 0;
   background: hsl(var(--muted) / 0.3);
-  /* Subtle background */
-  padding-top: 0.5rem;
-  padding-bottom: 0.5rem;
+  padding-top: 0.45rem;
+  padding-bottom: 0.45rem;
   border-radius: 0 0.5rem 0.5rem 0;
-  /* Rounded right corners */
-  /* Rounded right corners */
 }
 
 .ProseMirror code {
@@ -217,19 +276,16 @@
 /* Table Styles - Ensure content is compact */
 .ProseMirror table p {
   margin: 0;
-  /* Remove paragraph margin inside tables */
   line-height: var(--table-line-height, 1.2);
-  /* Use CSS variable with fallback */
-  /* Tighter line height for table content */
 }
 
 .ProseMirror table {
   border-collapse: collapse;
   margin: 1em 0;
-  /* Add some vertical space around the table itself */
   overflow: hidden;
   table-layout: fixed;
   width: 100%;
+  border-radius: 0.5rem;
 }
 
 .ProseMirror td,
@@ -240,7 +296,6 @@
   box-sizing: border-box;
   min-width: 1em;
   padding: 2px 4px;
-  /* Further reduced padding */
   position: relative;
   vertical-align: top;
 }
@@ -249,13 +304,12 @@
   background-color: hsl(var(--muted));
   font-weight: bold;
   text-align: left;
-  /* Make header borders visible by using a contrasting color if bg matches border */
   border-color: hsl(var(--foreground) / 0.1);
 }
 
 /* AI Content Style */
 .ai-content {
-  font-family: "KaiTi", "STKaiti", "楷体", "Georgia", serif;
+  font-family: "KaiTi", "STKaiti", "Kaiti SC", "Noto Serif SC", "Georgia", serif;
   font-style: italic;
   font-weight: normal;
   color: hsl(var(--foreground));
@@ -265,7 +319,6 @@
 /* Specific fix for dark mode if needed, but opacity trick usually works */
 .dark .ProseMirror th {
   border-color: hsl(var(--background));
-  /* Use background color for borders in dark mode header to show separation */
 }
 
 /* Task List Styles */
@@ -279,7 +332,6 @@ ul[data-type="taskList"],
 .ProseMirror li[data-type="taskItem"] div,
 .ProseMirror li[data-type="taskItem"] label {
   line-height: normal !important;
-  /* Force tight line height for checkbox items */
   margin-top: 2px;
   margin-bottom: 2px;
 }
@@ -289,12 +341,15 @@ ul[data-type="taskList"],
 
 /* Override Highlight.js background for a softer look */
 .ProseMirror pre {
-  background: #2b313a !important;
-  /* Slightly lifted code block background for comfortable reading */
+  background: hsl(var(--code-bg)) !important;
+  border: 1px solid hsl(var(--border) / 0.5);
   border-radius: 0.5rem;
+  padding: 0.65rem 0.75rem;
+  margin: 0.95rem 0;
 }
 
 .hljs {
   background: transparent !important;
   /* Let pre handle the background */
 }
+
diff --git a/src/app/page.tsx b/src/app/page.tsx
index ddb9d7a..d50f74e 100644
--- a/src/app/page.tsx
+++ b/src/app/page.tsx
@@ -3,7 +3,7 @@
 import { SidebarContent, ResizableSidebar } from "@/components/sidebar";
 import { Editor } from "@/components/editor";
 import { useEditorStore } from "@/lib/store";
-import { Hash, X, Plus, ChevronLeft, ChevronRight, Sparkles, Lock, Unlock, FolderOpen, History, RotateCcw } from "lucide-react";
+import { Hash, X, Plus, ChevronLeft, ChevronRight, ChevronDown, Sparkles, Lock, Unlock, FolderOpen, History, RotateCcw } from "lucide-react";
 import { useSettingsStore } from "@/lib/settings-store";
 import { exportPageAsMarkdown } from "@/lib/export";
 import { useMemo, useState } from "react";
@@ -12,6 +12,7 @@ import { useSearchStore } from "@/lib/search-store";
 import { type Editor as TiptapEditor } from "@tiptap/react";
 import { ImportProvider } from "@/components/import-context";
 import { AIChatPanel } from "@/components/chat/ai-chat-panel";
+import { SearchCommand } from "@/components/search-command";
 import { getBacklinks, getOutgoingLinks, getUnresolvedLinkTitles } from "@/lib/wiki-links";
 import { getPageHistory } from "@/lib/page-history";
 
@@ -34,6 +35,8 @@ export default function Home() {
   const [isAddingTag, setIsAddingTag] = useState(false);
   const [tagInput, setTagInput] = useState("");
   const [isIconPickerOpen, setIsIconPickerOpen] = useState(false);
+  const [isHistoryOpen, setIsHistoryOpen] = useState(false);
+  const [selectedHistoryIndex, setSelectedHistoryIndex] = useState(0);
 
   const breadcrumbs = useMemo(() => {
     if (!activePage) return [];
@@ -68,6 +71,7 @@ export default function Home() {
     if (!activePage || activePage.type !== "file") return [];
     return getPageHistory(activePage.id);
   }, [activePage]);
+  const effectiveHistoryIndex = Math.min(selectedHistoryIndex, Math.max(localHistory.length - 1, 0));
 
   const addTag = () => {
     if (!activePage) return;
@@ -93,6 +97,8 @@ export default function Home() {
   return (
     <ImportProvider>
       <div className="relative flex h-[100dvh] w-full overflow-hidden bg-background">
+        <SearchCommand />
+
         <div className={cn(activePageId ? "hidden" : "block h-full flex-1 md:hidden")}>
           <SidebarContent />
         </div>
@@ -102,50 +108,50 @@ export default function Home() {
         <main className={cn("relative z-0 flex h-full flex-1 flex-col overflow-hidden", !activePageId && "hidden md:flex")}>
           {activePage ? (
             <div className="flex-1 overflow-y-auto scroll-smooth">
-              <div className="mx-auto min-h-screen max-w-7xl px-4 py-6 md:px-16">
-                <div className="ui-enter group relative mb-8">
+              <div className="mx-auto min-h-screen max-w-7xl px-3 py-4 md:px-16 md:py-6">
+                <div className="ui-enter group relative mb-6 pt-10 md:mb-8 md:pt-0">
                   <button
-                    className="absolute -top-12 left-0 flex items-center gap-1 py-2 text-sm text-muted-foreground transition-colors hover:text-foreground md:hidden"
+                    className="absolute left-0 top-0 flex h-9 items-center gap-1 py-2 text-sm text-muted-foreground transition-colors hover:text-foreground md:hidden"
                     onClick={() => useEditorStore.getState().setActivePageId(null)}
                   >
                     <ChevronLeft size={18} />
                     返回列表
                   </button>
 
-                  <div className="mb-4 flex flex-wrap items-center gap-1 text-sm text-muted-foreground">
+                  <div className="mb-3 flex flex-wrap items-center gap-1 text-xs text-muted-foreground md:mb-4 md:text-sm">
                     {breadcrumbs.map((crumb, index) => (
-                      <div key={crumb.id} className="flex items-center gap-1">
+                      <div key={crumb.id} className="flex min-w-0 items-center gap-1">
                         {index > 0 && <ChevronRight size={14} className="opacity-50" />}
                         <button
                           onClick={() => useEditorStore.getState().setActivePageId(crumb.id)}
                           className={cn(
-                            "flex items-center gap-1 transition-colors hover:text-foreground hover:underline",
+                            "flex min-w-0 items-center gap-1 transition-colors hover:text-foreground hover:underline",
                             crumb.id === activePage.id && "pointer-events-none font-medium text-foreground"
                           )}
                         >
                           {crumb.icon && <span>{crumb.icon}</span>}
-                          <span>{crumb.title || "无标题"}</span>
+                          <span className="truncate">{crumb.title || "无标题"}</span>
                         </button>
                       </div>
                     ))}
                   </div>
 
-                  <div className="flex items-center gap-2">
-                    {activePage.icon && <span className="select-none text-3xl">{activePage.icon}</span>}
+                  <div className="flex items-start gap-2">
+                    {activePage.icon && <span className="select-none pt-0.5 text-[28px] md:text-3xl">{activePage.icon}</span>}
                     <input
                       value={activePage.title}
                       onChange={(e) => updatePage(activePage.id, { title: e.target.value })}
                       placeholder="无标题"
                       disabled={activePage.isLocked}
                       className={cn(
-                        "w-full border-none bg-transparent text-3xl font-bold text-foreground outline-none placeholder:text-muted-foreground/30",
+                        "w-full border-none bg-transparent text-2xl font-bold leading-tight text-foreground outline-none placeholder:text-muted-foreground/30 md:text-3xl",
                         activePage.isLocked && "cursor-not-allowed select-none opacity-80"
                       )}
                     />
                   </div>
                 </div>
 
-                <div className="ui-enter-delayed mb-6 flex flex-wrap items-center gap-2">
+                <div className="ui-enter-delayed relative z-20 mb-6 flex flex-wrap items-center gap-2">
                   {activePage.tags?.map((tag) => {
                     const colors = getTagColor(tag);
                     return (
@@ -167,7 +173,7 @@ export default function Home() {
                             const newTags = activePage.tags?.filter((t) => t !== tag) || [];
                             updatePage(activePage.id, { tags: newTags });
                           }}
-                          className="ml-1 rounded-full p-0.5 opacity-0 transition-all group-hover/tag:opacity-100 hover:bg-black/10 dark:hover:bg-white/10"
+                          className="ml-1 rounded-full p-1 opacity-100 transition-all hover:bg-black/10 md:p-0.5 md:opacity-0 md:group-hover/tag:opacity-100 dark:hover:bg-white/10"
                           title="移除标签"
                         >
                           <X size={10} />
@@ -205,7 +211,7 @@ export default function Home() {
                     </button>
                   )}
 
-                  <div className="relative">
+                  <div className="relative z-30">
                     <button
                       onClick={() => setIsIconPickerOpen((v) => !v)}
                       className="ui-btn-secondary px-2 py-1 text-xs text-muted-foreground"
@@ -213,8 +219,8 @@ export default function Home() {
                       <Sparkles size={12} /> {activePage.icon ? "更换图标" : "添加图标"}
                     </button>
                     {isIconPickerOpen && (
-                      <div className="ui-card absolute left-0 top-full z-50 mt-1 w-80 p-2 shadow-xl animate-in fade-in zoom-in-95">
-                        <div className="grid h-48 grid-cols-8 gap-1 overflow-y-auto pr-1">
+                      <div className="ui-card absolute left-0 top-full z-[120] mt-1 w-[min(92vw,20rem)] p-2 shadow-xl animate-in fade-in zoom-in-95 sm:w-80">
+                        <div className="grid h-48 grid-cols-6 gap-1 overflow-y-auto pr-1 sm:grid-cols-8">
                           {ICONS.map((icon) => (
                             <button
                               key={icon}
@@ -258,7 +264,7 @@ export default function Home() {
                   </button>
 
                   {activePage.updatedAt && (
-                    <div className="ml-1 h-4 border-l pl-2 text-xs text-muted-foreground/50">
+                    <div className="w-full pt-0.5 text-[11px] text-muted-foreground/60 md:ml-1 md:h-4 md:w-auto md:border-l md:pl-2 md:pt-0 md:text-xs md:text-muted-foreground/50">
                       {new Date(activePage.updatedAt).toLocaleString("zh-CN", {
                         timeZone: timezone || "Asia/Shanghai",
                         hour12: false,
@@ -268,7 +274,7 @@ export default function Home() {
                 </div>
 
                 {activePage.type === "folder" ? (
-                  <div className="ui-card ui-enter flex h-[50vh] flex-col items-center justify-center gap-3 text-muted-foreground">
+                  <div className="ui-card ui-enter flex h-[45vh] flex-col items-center justify-center gap-3 text-muted-foreground md:h-[50vh]">
                     <div className="ui-float rounded-2xl border border-border/70 bg-muted/40 p-4">
                       <FolderOpen size={34} className="text-primary/80" />
                     </div>
@@ -287,8 +293,8 @@ export default function Home() {
                       editable={!activePage.isLocked}
                     />
 
-                    <section className="ui-enter mt-8 space-y-4">
-                      <div className="ui-card p-4">
+                    <section className="ui-enter mt-6 space-y-3 md:mt-8 md:space-y-4">
+                      <div className="ui-card p-3 md:p-4">
                         <h3 className="text-sm font-semibold text-foreground">关联页面</h3>
                         <p className="mt-1 text-xs text-muted-foreground">在正文中使用 `[[页面名]]` 自动建立链接关系，支持 `Ctrl/Cmd + 点击` 跳转。</p>
                         <div className="mt-3 flex flex-wrap gap-2">
@@ -309,7 +315,7 @@ export default function Home() {
                         </div>
                       </div>
 
-                      <div className="ui-card p-4">
+                      <div className="ui-card p-3 md:p-4">
                         <h3 className="text-sm font-semibold text-foreground">反向链接</h3>
                         <p className="mt-1 text-xs text-muted-foreground">这些页面提到了当前页面。</p>
                         <div className="mt-3 flex flex-wrap gap-2">
@@ -330,7 +336,7 @@ export default function Home() {
                         </div>
                       </div>
 
-                      <div className="ui-card p-4">
+                      <div className="ui-card p-3 md:p-4">
                         <h3 className="text-sm font-semibold text-foreground">未解析链接</h3>
                         <p className="mt-1 text-xs text-muted-foreground">这些 `[[页面名]]` 还没有对应页面，可一键创建。</p>
                         <div className="mt-3 flex flex-wrap gap-2">
@@ -353,47 +359,78 @@ export default function Home() {
                         </div>
                       </div>
 
-                      <div className="ui-card p-4">
-                        <div className="flex items-center gap-2">
-                          <History size={14} className="text-muted-foreground" />
-                          <h3 className="text-sm font-semibold text-foreground">本地历史版本</h3>
-                        </div>
+                      <div className="ui-card p-3 md:p-4">
+                        <button
+                          onClick={() => setIsHistoryOpen((v) => !v)}
+                          className="flex w-full items-center justify-between rounded-md px-1 py-1 text-left transition-colors hover:bg-muted/45"
+                          aria-expanded={isHistoryOpen}
+                          aria-label="切换本地历史版本面板"
+                        >
+                          <div className="flex items-center gap-2">
+                            <History size={14} className="text-muted-foreground" />
+                            <h3 className="text-sm font-semibold text-foreground">本地历史版本</h3>
+                            <span className="rounded bg-muted px-1.5 py-0.5 text-[10px] text-muted-foreground">{localHistory.length}</span>
+                          </div>
+                          <ChevronDown size={15} className={cn("text-muted-foreground transition-transform", isHistoryOpen && "rotate-180")} />
+                        </button>
                         <p className="mt-1 text-xs text-muted-foreground">自动保存最近修改快照（当前浏览器本地）。</p>
-                        <div className="mt-3 space-y-2">
-                          {localHistory.length > 0 ? (
-                            localHistory.slice(0, 8).map((snapshot, index) => (
-                              <div key={`${snapshot.timestamp}-${index}`} className="flex items-center justify-between rounded-md border border-border/60 bg-muted/20 px-2.5 py-2">
-                                <div className="min-w-0">
+                        {isHistoryOpen && (
+                          <div className="mt-3 space-y-3">
+                            {localHistory.length > 0 ? (
+                              <>
+                                <div className="rounded-lg border border-border/60 bg-muted/20 p-2">
+                                  <label className="mb-1 block text-[11px] text-muted-foreground">选择要恢复的版本</label>
+                                  <select
+                                    value={selectedHistoryIndex}
+                                    onChange={(e) => setSelectedHistoryIndex(parseInt(e.target.value, 10))}
+                                    className="ui-select h-9 py-1 text-xs"
+                                  >
+                                    {localHistory.slice(0, 20).map((snapshot, index) => (
+                                      <option key={`${snapshot.timestamp}-${index}`} value={index}>
+                                        {new Date(snapshot.timestamp).toLocaleString("zh-CN", {
+                                          timeZone: timezone || "Asia/Shanghai",
+                                          hour12: false,
+                                        })}
+                                        {` · ${snapshot.title || "无标题"}`}
+                                      </option>
+                                    ))}
+                                  </select>
+                                </div>
+                                <div className="rounded-md border border-border/60 bg-muted/15 px-2.5 py-2">
                                   <div className="truncate text-xs text-foreground">
-                                    {snapshot.title || "无标题"}
+                                    {localHistory[effectiveHistoryIndex]?.title || "无标题"}
                                   </div>
                                   <div className="text-[11px] text-muted-foreground">
-                                    {new Date(snapshot.timestamp).toLocaleString("zh-CN", {
-                                      timeZone: timezone || "Asia/Shanghai",
-                                      hour12: false,
-                                    })}
+                                    {localHistory[effectiveHistoryIndex]
+                                      ? new Date(localHistory[effectiveHistoryIndex].timestamp).toLocaleString("zh-CN", {
+                                          timeZone: timezone || "Asia/Shanghai",
+                                          hour12: false,
+                                        })
+                                      : "-"}
                                   </div>
                                 </div>
                                 <button
                                   onClick={async () => {
+                                    const target = localHistory[effectiveHistoryIndex];
+                                    if (!target || !activePage) return;
                                     const ok = window.confirm("恢复该历史版本后将覆盖当前内容，是否继续？");
-                                    if (!ok || !activePage) return;
+                                    if (!ok) return;
                                     await updatePage(activePage.id, {
-                                      title: snapshot.title,
-                                      content: snapshot.content,
+                                      title: target.title,
+                                      content: target.content,
                                     });
                                   }}
-                                  className="ui-btn-secondary px-2 py-1 text-xs"
+                                  className="ui-btn-secondary h-9 w-full justify-center px-2 py-1 text-xs sm:h-auto sm:w-auto sm:justify-start"
                                 >
                                   <RotateCcw size={12} />
-                                  恢复
+                                  恢复选中版本
                                 </button>
-                              </div>
-                            ))
-                          ) : (
-                            <span className="text-xs text-muted-foreground">暂无历史记录</span>
-                          )}
-                        </div>
+                              </>
+                            ) : (
+                              <span className="text-xs text-muted-foreground">暂无历史记录</span>
+                            )}
+                          </div>
+                        )}
                       </div>
                     </section>
                   </div>
@@ -401,13 +438,15 @@ export default function Home() {
               </div>
             </div>
           ) : (
-            <div className="ui-enter flex h-full flex-col items-center justify-center gap-4 text-muted-foreground">
-              <div className="ui-float rounded-2xl border border-border/70 bg-muted/40 p-4">
-                <span className="text-4xl">🧠</span>
-              </div>
-              <div className="space-y-1 text-center">
-                <h3 className="text-lg font-semibold text-foreground">欢迎使用 NoteAI</h3>
-                <p className="text-sm text-muted-foreground/90">在左侧选择一个页面，或新建文档开始写作。</p>
+            <div className="ui-enter flex h-full items-center justify-center p-4 md:p-8">
+              <div className="ui-card flex w-full max-w-md flex-col items-center gap-3 px-6 py-8 text-center text-muted-foreground">
+                <div className="ui-float rounded-2xl border border-border/70 bg-muted/40 p-4">
+                  <span className="text-4xl">🧠</span>
+                </div>
+                <div className="space-y-1">
+                  <h3 className="text-lg font-semibold text-foreground">欢迎使用 NoteAI</h3>
+                  <p className="text-sm text-muted-foreground/90">在左侧选择一个页面，或新建文档开始写作。</p>
+                </div>
               </div>
             </div>
           )}
diff --git a/src/app/settings/page.tsx b/src/app/settings/page.tsx
index 1e2108e..29f004b 100644
--- a/src/app/settings/page.tsx
+++ b/src/app/settings/page.tsx
@@ -1,7 +1,7 @@
 "use client";
 
 import { useState } from "react";
-import { Lock, Save, Sparkles, Type, Upload, Download } from "lucide-react";
+import { Lock, Save, Sparkles, Type, Upload, Download, Loader2 } from "lucide-react";
 import { ResizableSidebar } from "@/components/sidebar";
 import { PromptManagement } from "@/components/settings/prompt-management";
 import { ImportProvider } from "@/components/import-context";
@@ -28,6 +28,8 @@ export default function SettingsPage() {
     const [currentPassword, setCurrentPassword] = useState("");
     const [newPassword, setNewPassword] = useState("");
     const [confirmPassword, setConfirmPassword] = useState("");
+    const [isExporting, setIsExporting] = useState(false);
+    const [isRestoring, setIsRestoring] = useState(false);
     const [msg, setMsg] = useState<{ type: "success" | "error"; text: string } | null>(null);
 
     const handlePasswordChange = async (e: React.FormEvent) => {
@@ -62,7 +64,7 @@ export default function SettingsPage() {
 
     return (
         <ImportProvider>
-            <div className="flex h-screen w-full bg-background overflow-hidden">
+            <div className="flex h-[100dvh] w-full overflow-hidden bg-background">
                 <ResizableSidebar />
                 <main className="flex-1 h-full overflow-y-auto p-4 md:p-10">
                     <div className="mx-auto max-w-3xl space-y-8 pb-16">
@@ -71,10 +73,10 @@ export default function SettingsPage() {
                             <p className="text-muted-foreground">管理外观、AI、安全与备份。</p>
                         </header>
 
-                        <section className="ui-card ui-enter-delayed p-6 space-y-5">
+                        <section className="ui-card ui-enter-delayed space-y-5 p-4 md:p-6">
                             <div className="flex items-center gap-2 border-b pb-2">
                                 <Type size={18} className="text-primary" />
-                                <h2 className="text-xl font-semibold">外观设置</h2>
+                                <h2 className="text-lg font-semibold md:text-xl">外观设置</h2>
                             </div>
 
                             <div className="grid gap-4 md:grid-cols-2">
@@ -149,10 +151,10 @@ export default function SettingsPage() {
                             </label>
                         </section>
 
-                        <section className="ui-card ui-enter-delayed p-6 space-y-5">
+                        <section className="ui-card ui-enter-delayed space-y-5 p-4 md:p-6">
                             <div className="flex items-center gap-2 border-b pb-2">
                                 <Sparkles size={18} className="text-primary" />
-                                <h2 className="text-xl font-semibold">AI 配置</h2>
+                                <h2 className="text-lg font-semibold md:text-xl">AI 配置</h2>
                             </div>
 
                             <div className="space-y-3">
@@ -191,14 +193,14 @@ export default function SettingsPage() {
                             </div>
                         </section>
 
-                        <section className="ui-card ui-enter-delayed p-6">
+                        <section className="ui-card ui-enter-delayed p-4 md:p-6">
                             <PromptManagement />
                         </section>
 
-                        <section className="ui-card ui-enter-delayed p-6 space-y-5">
+                        <section className="ui-card ui-enter-delayed space-y-5 p-4 md:p-6">
                             <div className="flex items-center gap-2 border-b pb-2">
                                 <Lock size={18} className="text-primary" />
-                                <h2 className="text-xl font-semibold">安全设置</h2>
+                                <h2 className="text-lg font-semibold md:text-xl">安全设置</h2>
                             </div>
 
                             <form onSubmit={handlePasswordChange} className="space-y-3 max-w-md">
@@ -243,30 +245,43 @@ export default function SettingsPage() {
                             </form>
                         </section>
 
-                        <section className="ui-card ui-enter-delayed p-6 space-y-4">
-                            <h2 className="text-xl font-semibold">备份与恢复</h2>
+                        <section className="ui-card ui-enter-delayed space-y-4 p-4 md:p-6">
+                            <h2 className="text-lg font-semibold md:text-xl">备份与恢复</h2>
                             <p className="text-sm text-muted-foreground">恢复会覆盖当前全部文档，请谨慎操作。</p>
 
                             <div className="flex flex-col gap-3 sm:flex-row">
                                 <button
                                     onClick={async () => {
-                                        const { pages } = await import("@/lib/store").then((m) => m.useEditorStore.getState());
-                                        const { exportAllPagesAsZip } = await import("@/lib/export");
-                                        await exportAllPagesAsZip(pages);
+                                        if (isExporting || isRestoring) return;
+                                        setIsExporting(true);
+                                        try {
+                                            const { pages } = await import("@/lib/store").then((m) => m.useEditorStore.getState());
+                                            const { exportAllPagesAsZip } = await import("@/lib/export");
+                                            await exportAllPagesAsZip(pages);
+                                        } finally {
+                                            setIsExporting(false);
+                                        }
                                     }}
+                                    disabled={isExporting || isRestoring}
+                                    aria-busy={isExporting}
                                     className="ui-btn-secondary"
                                 >
-                                    <Download size={14} />
-                                    下载备份 (Zip)
+                                    {isExporting ? <Loader2 size={14} className="animate-spin" /> : <Download size={14} />}
+                                    {isExporting ? "导出中..." : "下载备份 (Zip)"}
                                 </button>
 
-                                <label className="ui-btn inline-flex cursor-pointer border border-destructive/30 bg-destructive/10 text-destructive hover:bg-destructive/20">
-                                    <Upload size={14} />
-                                    上传备份并恢复
+                                <label
+                                    className={`ui-btn inline-flex border border-destructive/30 bg-destructive/10 text-destructive hover:bg-destructive/20 ${
+                                        isExporting || isRestoring ? "cursor-not-allowed opacity-55" : "cursor-pointer"
+                                    }`}
+                                >
+                                    {isRestoring ? <Loader2 size={14} className="animate-spin" /> : <Upload size={14} />}
+                                    {isRestoring ? "恢复中..." : "上传备份并恢复"}
                                     <input
                                         type="file"
                                         accept=".zip"
                                         className="hidden"
+                                        disabled={isExporting || isRestoring}
                                         onChange={async (e) => {
                                             const file = e.target.files?.[0];
                                             if (!file) return;
@@ -284,6 +299,7 @@ export default function SettingsPage() {
                                             }
 
                                             try {
+                                                setIsRestoring(true);
                                                 const formData = new FormData();
                                                 formData.append("file", file);
                                                 const res = await fetch("/api/settings/restore", { method: "POST", body: formData });
@@ -295,6 +311,7 @@ export default function SettingsPage() {
                                             } catch (error) {
                                                 alert(String(error));
                                             } finally {
+                                                setIsRestoring(false);
                                                 e.target.value = "";
                                             }
                                         }}
diff --git a/src/components/ai-assist.tsx b/src/components/ai-assist.tsx
index e3c2fb3..7a531f4 100644
--- a/src/components/ai-assist.tsx
+++ b/src/components/ai-assist.tsx
@@ -18,13 +18,13 @@ export function AIAssist({ onSuggest, isOpen, onClose }: AIAssistProps) {
     if (typeof document === "undefined") return null;
 
     return createPortal(
-        <div className="fixed inset-0 z-[9999] flex items-center justify-center bg-black/25 backdrop-blur-[2px]" onClick={onClose}>
-            <div className="ui-card w-[320px] overflow-hidden" onClick={(e) => e.stopPropagation()}>
+        <div className="fixed inset-0 z-[9999] flex items-center justify-center bg-black/25 p-3 backdrop-blur-[2px]" onClick={onClose}>
+            <div className="ui-card w-full max-w-[320px] overflow-hidden" onClick={(e) => e.stopPropagation()}>
                 <div className="flex items-center gap-2 border-b border-border/60 bg-muted/40 px-4 py-3 text-sm font-medium text-muted-foreground">
                     <Sparkles size={16} className="text-primary" />
                     AI 写作助手
                 </div>
-                <div className="max-h-[320px] space-y-1 overflow-y-auto p-2">
+                <div className="max-h-[55vh] space-y-1 overflow-y-auto p-2 sm:max-h-[320px]">
                     {prompts.map((prompt) => (
                         <button
                             key={prompt.id}
diff --git a/src/components/chat/ai-chat-panel.tsx b/src/components/chat/ai-chat-panel.tsx
index f4c5756..c6d8e23 100644
--- a/src/components/chat/ai-chat-panel.tsx
+++ b/src/components/chat/ai-chat-panel.tsx
@@ -39,6 +39,18 @@ export function AIChatPanel({ editor, isOpen, onClose }: AIChatPanelProps) {
         messagesEndRef.current?.scrollIntoView({ behavior: "smooth" });
     }, [messages]);
 
+    useEffect(() => {
+        if (!isOpen) return;
+        const onKeyDown = (event: KeyboardEvent) => {
+            if (event.key === "Escape") {
+                event.preventDefault();
+                onClose();
+            }
+        };
+        window.addEventListener("keydown", onKeyDown);
+        return () => window.removeEventListener("keydown", onKeyDown);
+    }, [isOpen, onClose]);
+
     const handleStop = () => {
         if (abortControllerRef.current) {
             abortControllerRef.current.abort();
@@ -141,7 +153,12 @@ export function AIChatPanel({ editor, isOpen, onClose }: AIChatPanelProps) {
     if (!isOpen) return null;
 
     return (
-        <div className="fixed bottom-0 right-0 top-0 z-50 flex w-96 flex-col border-l border-border/70 bg-background shadow-xl animate-in slide-in-from-right duration-300">
+        <div
+            className="fixed inset-0 z-50 flex w-full flex-col bg-background shadow-xl animate-in slide-in-from-right duration-300 md:left-auto md:w-96 md:border-l md:border-border/70"
+            role="dialog"
+            aria-modal="true"
+            aria-label="AI 助手对话面板"
+        >
             <div className="flex items-center justify-between border-b border-border/70 p-4">
                 <div className="flex items-center gap-2">
                     <Sparkles className="h-5 w-5 text-primary" />
@@ -151,8 +168,8 @@ export function AIChatPanel({ editor, isOpen, onClose }: AIChatPanelProps) {
                     </div>
                 </div>
                 <div className="flex items-center gap-2">
-                    <span className="mr-1 text-xs text-muted-foreground">估算 Tokens: {tokenCount}</span>
-                    <button onClick={onClose} className="ui-icon-btn h-8 w-8">
+                    <span className="mr-1 hidden text-xs text-muted-foreground sm:inline">估算 Tokens: {tokenCount}</span>
+                    <button onClick={onClose} className="ui-icon-btn h-10 w-10 md:h-8 md:w-8" aria-label="关闭 AI 助手">
                         <X size={18} />
                     </button>
                 </div>
@@ -177,7 +194,7 @@ export function AIChatPanel({ editor, isOpen, onClose }: AIChatPanelProps) {
                         </div>
                         <div
                             className={cn(
-                                "group relative max-w-[85%] rounded-lg p-3 text-sm",
+                                "group relative max-w-[92%] rounded-lg p-3 text-sm sm:max-w-[85%]",
                                 msg.role === "user" ? "bg-primary text-primary-foreground" : "bg-muted text-foreground",
                                 msg.role === "system" && "w-full max-w-full bg-destructive/10 text-destructive"
                             )}
@@ -192,7 +209,7 @@ export function AIChatPanel({ editor, isOpen, onClose }: AIChatPanelProps) {
                             )}
 
                             {msg.role === "assistant" && !isLoading && (
-                                <div className="absolute -bottom-6 left-0 flex gap-2 opacity-0 transition-opacity group-hover:opacity-100">
+                                <div className="mt-2 flex gap-2 opacity-100 sm:absolute sm:-bottom-6 sm:left-0 sm:mt-0 sm:opacity-0 sm:transition-opacity sm:group-hover:opacity-100">
                                     <button
                                         onClick={() => handleInsert(msg.content)}
                                         className="flex items-center gap-1 rounded border bg-background px-1 py-1 text-xs shadow hover:bg-muted"
@@ -215,20 +232,21 @@ export function AIChatPanel({ editor, isOpen, onClose }: AIChatPanelProps) {
                 <div ref={messagesEndRef} />
             </div>
 
-            <div className="border-t border-border/70 bg-muted/20 p-4">
+            <div className="border-t border-border/70 bg-muted/20 p-3 pb-[max(0.75rem,env(safe-area-inset-bottom))] sm:p-4">
                 <div className="mb-2 flex items-center justify-between">
-                    <label className="flex cursor-pointer select-none items-center gap-2 text-xs text-muted-foreground">
+                    <label className="flex cursor-pointer select-none items-center gap-2 text-[11px] text-muted-foreground sm:text-xs">
                         <input
                             type="checkbox"
                             checked={useContext}
                             onChange={(e) => setUseContext(e.target.checked)}
-                            className="rounded border-input text-primary focus:ring-primary"
+                            className="h-5 w-5 rounded border-input text-primary focus:ring-primary"
+                            aria-label="关联当前文档上下文"
                         />
                         关联当前文档上下文
                     </label>
                     <button
                         onClick={() => setMessages([])}
-                        className="flex items-center gap-1 text-xs text-muted-foreground hover:text-foreground"
+                        className="flex items-center gap-1 text-[11px] text-muted-foreground hover:text-foreground sm:text-xs"
                         title="清空对话"
                     >
                         <Eraser size={12} /> 清空
@@ -246,6 +264,7 @@ export function AIChatPanel({ editor, isOpen, onClose }: AIChatPanelProps) {
                         }}
                         placeholder="输入消息..."
                         className="min-h-[86px] w-full resize-none rounded-md border border-input bg-background p-3 pr-10 text-sm outline-none focus:ring-1 focus:ring-primary"
+                        aria-label="输入给 AI 的消息"
                     />
                     <button
                         onClick={isLoading ? handleStop : handleSend}
@@ -255,6 +274,7 @@ export function AIChatPanel({ editor, isOpen, onClose }: AIChatPanelProps) {
                             isLoading ? "bg-red-500 text-white" : "bg-primary text-primary-foreground"
                         )}
                         title={isLoading ? "停止生成" : "发送"}
+                        aria-label={isLoading ? "停止生成" : "发送消息"}
                     >
                         {isLoading ? <div className="h-4 w-4 animate-pulse rounded-sm bg-current" /> : <Send size={16} />}
                     </button>
diff --git a/src/components/confirm-provider.tsx b/src/components/confirm-provider.tsx
index 968b0ab..ff1a391 100644
--- a/src/components/confirm-provider.tsx
+++ b/src/components/confirm-provider.tsx
@@ -71,13 +71,14 @@ export function ConfirmProvider({ children }: { children: React.ReactNode }) {
                         )}
 
                         <div className="mt-6 flex justify-end gap-2">
-                            <button type="button" onClick={() => closeWith(false)} className="ui-btn-secondary">
+                            <button type="button" onClick={() => closeWith(false)} className="ui-btn-secondary" aria-label={request?.cancelText || "取消"}>
                                 {request?.cancelText || "取消"}
                             </button>
                             <button
                                 type="button"
                                 onClick={() => closeWith(true)}
                                 className={request?.tone === "danger" ? "ui-btn-danger" : "ui-btn-primary"}
+                                aria-label={request?.confirmText || "确认"}
                             >
                                 {request?.confirmText || "确认"}
                             </button>
diff --git a/src/components/editor.tsx b/src/components/editor.tsx
index 8a42d7c..78f98f8 100644
--- a/src/components/editor.tsx
+++ b/src/components/editor.tsx
@@ -287,7 +287,7 @@ export function Editor({ content, onChange, onEditorReady, onToggleAI, onExport,
                 </div>
             )}
 
-            <div className="flex-1 mt-4">
+            <div className="mt-3 flex-1 md:mt-4">
                 <EditorContent editor={editor} />
             </div>
 
@@ -300,7 +300,7 @@ export function Editor({ content, onChange, onEditorReady, onToggleAI, onExport,
                         setShowAI(!showAI);
                     }
                 }}
-                className={`fixed bottom-8 right-8 p-3 rounded-full shadow-lg hover:scale-110 transition-transform z-40 ${
+                className={`fixed bottom-[max(1rem,env(safe-area-inset-bottom))] right-4 p-3 rounded-full shadow-lg hover:scale-110 transition-transform z-40 md:bottom-8 md:right-8 ${
                     isGenerating ? "bg-red-500 text-white animate-pulse" : "bg-primary text-primary-foreground"
                 }`}
                 title={isGenerating ? "停止生成" : "AI 助手"}
diff --git a/src/components/editor/code-block.tsx b/src/components/editor/code-block.tsx
index 0d02a23..e5b80e5 100644
--- a/src/components/editor/code-block.tsx
+++ b/src/components/editor/code-block.tsx
@@ -1,4 +1,4 @@
-"use client";
+"use client";
 
 import { NodeViewContent, NodeViewWrapper, NodeViewProps } from "@tiptap/react";
 import React, { useMemo } from "react";
@@ -13,135 +13,89 @@ export function CodeBlockComponent({
     editor,
     getPos,
 }: NodeViewProps) {
-    const codeBg = "#2b313a";
+    const codeBg = "hsl(var(--code-bg))";
     const { language: defaultLanguage } = node.attrs;
     const { textContent } = node;
     const [copied, setCopied] = React.useState(false);
 
     const languages = extension.options.lowlight ? extension.options.lowlight.listLanguages() : [];
 
-    // Custom logic to prioritize common languages and ensure 'html' is present
-    const popularLanguages = ['html', 'javascript', 'typescript', 'css', 'json', 'python', 'java', 'go', 'bash', 'sql'];
-    const otherLanguages = languages.filter((lang: string) => !popularLanguages.includes(lang) && lang !== 'xml'); // Hide xml if we show html
-
-    // We map 'html' to 'xml' when saving if needed, but for the selector we want 'html'
-    // Actually highlight.js understands 'html' if aliased. 
-    // Let's just create a flat list for the selector, but maybe we want groups?
-    // For now, just a flat sorted list: Popular + Others
+    const popularLanguages = ["html", "javascript", "typescript", "css", "json", "python", "java", "go", "bash", "sql"];
+    const otherLanguages = languages.filter((lang: string) => !popularLanguages.includes(lang) && lang !== "xml");
     const displayLanguages = Array.from(new Set([...popularLanguages, ...otherLanguages]));
 
     const insertAbove = () => {
-        if (typeof getPos === 'function') {
+        if (typeof getPos === "function") {
             const pos = getPos();
-            if (typeof pos !== 'number') return;
-            editor.chain()
-                .insertContentAt(pos, { type: 'paragraph' })
-                .focus()
-                .setTextSelection(pos + 1)
-                .scrollIntoView()
-                .run();
+            if (typeof pos !== "number") return;
+            editor.chain().insertContentAt(pos, { type: "paragraph" }).focus().setTextSelection(pos + 1).scrollIntoView().run();
         }
     };
 
     const insertBelow = () => {
-        if (typeof getPos === 'function') {
+        if (typeof getPos === "function") {
             const pos = getPos();
-            if (typeof pos !== 'number') return;
+            if (typeof pos !== "number") return;
             const targetPos = pos + node.nodeSize;
-            editor.chain()
-                .insertContentAt(targetPos, { type: 'paragraph' })
-                .focus()
-                .setTextSelection(targetPos + 1)
-                .scrollIntoView()
-                .run();
+            editor.chain().insertContentAt(targetPos, { type: "paragraph" }).focus().setTextSelection(targetPos + 1).scrollIntoView().run();
         }
     };
 
     const handleCopy = () => {
-        const code = textContent;
-        navigator.clipboard.writeText(code);
+        navigator.clipboard.writeText(textContent);
         setCopied(true);
         setTimeout(() => setCopied(false), 2000);
     };
 
-    // Calculate line numbers
     const lineNumbers = useMemo(() => {
-        const lines = textContent.split('\n').length;
+        const lines = textContent.split("\n").length;
         return Array.from({ length: lines }, (_, i) => i + 1);
     }, [textContent]);
 
     return (
-        <NodeViewWrapper className="relative group code-block rounded-lg border border-border/40 my-4 shadow-sm overflow-hidden" style={{ backgroundColor: codeBg }}>
-            {/* Header */}
-            <div className="flex items-center justify-between px-3 py-2 bg-[#2f2f35] border-b border-white/5 text-xs select-none text-zinc-400">
+        <NodeViewWrapper className="group code-block relative my-4 overflow-hidden rounded-lg border border-border/40 shadow-sm" style={{ backgroundColor: codeBg }}>
+            <div
+                className="flex select-none items-center justify-between border-b border-border/50 px-3 py-2 text-xs text-zinc-400"
+                style={{ backgroundColor: "hsl(var(--code-bg) / 0.9)" }}
+            >
                 <div className="flex items-center gap-2">
-
                     <LanguageSelector
-                        language={defaultLanguage || 'null'}
+                        language={defaultLanguage || "null"}
                         onChange={(val) => {
-                            // Map helpful aliases if necessary, though highlight.js is smart.
-                            // But Tiptap highlight extension might strict check?
-                            // Usually 'html' works fine if the grammar is loaded.
-                            // Since we use 'common', 'xml' is the grammar. 'html' is alias.
-                            // If I pass 'html', does lowlight find it? Yes if alias is registered.
-                            // Earlier we tried to register alias but reverted.
-                            // Let's force 'xml' if 'html' is selected to be safe, OR rely on 'xml' being the backend.
-                            // Actually, let's keep it simple: Pass 'val'.
-                            updateAttributes({ language: val })
+                            updateAttributes({ language: val });
                         }}
                         languages={displayLanguages}
                     />
                 </div>
 
-                <div className="flex items-center gap-1 opacity-0 group-hover:opacity-100 transition-opacity">
-                    <button
-                        onClick={insertAbove}
-                        className="hover:text-white hover:bg-white/10 p-1.5 rounded transition-all"
-                        title="在上方插入"
-                    >
+                <div className="flex items-center gap-1 opacity-0 transition-opacity group-hover:opacity-100">
+                    <button onClick={insertAbove} className="rounded p-1.5 transition-all hover:bg-white/10 hover:text-white" title="在上方插入">
                         <ArrowUpToLine size={14} />
                     </button>
-                    <button
-                        onClick={insertBelow}
-                        className="hover:text-white hover:bg-white/10 p-1.5 rounded transition-all"
-                        title="在下方插入"
-                    >
+                    <button onClick={insertBelow} className="rounded p-1.5 transition-all hover:bg-white/10 hover:text-white" title="在下方插入">
                         <ArrowDownToLine size={14} />
                     </button>
-                    <div className="w-px h-3 bg-white/10 mx-1" />
-                    <button
-                        onClick={handleCopy}
-                        className="hover:text-white hover:bg-white/10 p-1.5 rounded transition-all"
-                        title="复制"
-                    >
+                    <div className="mx-1 h-3 w-px bg-white/10" />
+                    <button onClick={handleCopy} className="rounded p-1.5 transition-all hover:bg-white/10 hover:text-white" title="复制代码">
                         {copied ? <Check size={14} className="text-green-500" /> : <Copy size={14} />}
                     </button>
-                    <button
-                        onClick={() => deleteNode()}
-                        className="hover:text-red-400 hover:bg-white/10 p-1.5 rounded transition-all"
-                        title="删除"
-                    >
+                    <button onClick={() => deleteNode()} className="rounded p-1.5 transition-all hover:bg-white/10 hover:text-red-400" title="删除代码块">
                         <Trash2 size={14} />
                     </button>
                 </div>
             </div>
 
-            {/* Code Area with Line Numbers - Use grid for better alignment control */}
             <div className="relative grid grid-cols-[auto_1fr] font-mono text-sm leading-6" style={{ backgroundColor: codeBg }}>
-                {/* Line Numbers Gutter */}
-                <div
-                    className="py-4 px-2 text-right select-none border-r border-white/5 text-zinc-500"
-                    style={{ minWidth: '2.5rem' }}
-                    contentEditable={false}
-                >
+                <div className="select-none border-r border-white/5 px-2 py-4 text-right text-zinc-500" style={{ minWidth: "2.5rem" }} contentEditable={false}>
                     {lineNumbers.map((line) => (
-                        <div key={line} className="px-1">{line}</div>
+                        <div key={line} className="px-1">
+                            {line}
+                        </div>
                     ))}
                 </div>
 
-                {/* Actual Code Content */}
-                <pre className="overflow-x-auto !p-0 !my-0 !border-0 text-zinc-300 scrollbar-thin scrollbar-thumb-white/10 scrollbar-track-transparent" style={{ backgroundColor: codeBg }}>
-                    <NodeViewContent className="block min-w-full !p-4 !bg-transparent !whitespace-pre outline-none !font-mono !text-sm !leading-6" />
+                <pre className="scrollbar-thin scrollbar-track-transparent scrollbar-thumb-white/10 !my-0 !border-0 !p-0 overflow-x-auto text-zinc-300" style={{ backgroundColor: codeBg }}>
+                    <NodeViewContent className="block min-w-full !whitespace-pre !bg-transparent !p-4 !font-mono !text-sm !leading-6 outline-none" />
                 </pre>
             </div>
         </NodeViewWrapper>
diff --git a/src/components/editor/command-list.tsx b/src/components/editor/command-list.tsx
index 4a41dd3..89ec978 100644
--- a/src/components/editor/command-list.tsx
+++ b/src/components/editor/command-list.tsx
@@ -118,8 +118,8 @@ export class CommandList extends Component<CommandListProps, CommandListState> {
         let globalIndex = 0;
 
         return (
-            <div className="z-50 h-auto max-h-[500px] w-[800px] overflow-hidden rounded-xl border border-zinc-800 bg-zinc-950/95 shadow-2xl backdrop-blur-lg animate-in fade-in zoom-in-95 duration-200">
-                <div className="columns-3 gap-2 p-3 space-y-4">
+            <div className="z-50 h-auto max-h-[65vh] w-[min(92vw,800px)] overflow-hidden rounded-xl border border-zinc-800 bg-zinc-950/95 shadow-2xl backdrop-blur-lg animate-in fade-in zoom-in-95 duration-200">
+                <div className="columns-1 gap-2 p-2 space-y-3 sm:p-3 sm:space-y-4 md:columns-2 lg:columns-3">
                     {Object.entries(grouped).map(([groupName, groupItems]) => (
                         <div key={groupName} className="break-inside-avoid mb-4">
                             <div className="px-2 py-1.5 text-[10px] font-bold uppercase tracking-widest text-zinc-500 select-none mb-1">
diff --git a/src/components/editor/toolbar.tsx b/src/components/editor/toolbar.tsx
index 0fea2a3..ce9a9e4 100644
--- a/src/components/editor/toolbar.tsx
+++ b/src/components/editor/toolbar.tsx
@@ -1,13 +1,32 @@
-"use client";
+"use client";
 
 import { type Editor } from "@tiptap/react";
 import {
-    Bold, Italic, Strikethrough, Code,
-    Heading1, Heading2, Heading3,
-    List, ListOrdered, Quote,
-    Undo, Redo, Minus, RemoveFormatting,
-    AlignLeft, AlignCenter, AlignRight, CheckSquare, Link as LinkIcon, Image as ImageIcon,
-    Table as TableIcon, Sparkles, FileDown, SquareCode
+    Bold,
+    Italic,
+    Strikethrough,
+    Code,
+    Heading1,
+    Heading2,
+    Heading3,
+    List,
+    ListOrdered,
+    Quote,
+    Undo,
+    Redo,
+    Minus,
+    RemoveFormatting,
+    AlignLeft,
+    AlignCenter,
+    AlignRight,
+    CheckSquare,
+    Link as LinkIcon,
+    Image as ImageIcon,
+    Table as TableIcon,
+    Sparkles,
+    FileDown,
+    SquareCode,
+    type LucideIcon,
 } from "lucide-react";
 import { cn } from "@/lib/utils";
 
@@ -17,127 +36,43 @@ interface ToolbarProps {
     onExport?: () => void;
 }
 
+type ToolbarItem = {
+    icon?: LucideIcon;
+    title?: string;
+    action?: () => void;
+    isActive?: boolean;
+    disabled?: boolean;
+    divider?: boolean;
+};
+
 export function Toolbar({ editor, onToggleAI, onExport }: ToolbarProps) {
     if (!editor) {
         return null;
     }
 
-    const items = [
-        {
-            icon: Bold,
-            title: "加粗",
-            action: () => editor.chain().focus().toggleBold().run(),
-            isActive: editor.isActive("bold"),
-        },
-        {
-            icon: Italic,
-            title: "斜体",
-            action: () => editor.chain().focus().toggleItalic().run(),
-            isActive: editor.isActive("italic"),
-        },
-        {
-            icon: Strikethrough,
-            title: "删除线",
-            action: () => editor.chain().focus().toggleStrike().run(),
-            isActive: editor.isActive("strike"),
-        },
-        {
-            icon: Code,
-            title: "行内代码",
-            action: () => editor.chain().focus().toggleCode().run(),
-            isActive: editor.isActive("code"),
-        },
-        {
-            icon: SquareCode,
-            title: "代码块",
-            action: () => editor.chain().focus().toggleCodeBlock().run(),
-            isActive: editor.isActive("codeBlock"),
-        },
-        {
-            divider: true,
-        },
-        {
-            icon: Heading1,
-            title: "标题 1",
-            action: () => editor.chain().focus().toggleHeading({ level: 1 }).run(),
-            isActive: editor.isActive("heading", { level: 1 }),
-        },
-        {
-            icon: Heading2,
-            title: "标题 2",
-            action: () => editor.chain().focus().toggleHeading({ level: 2 }).run(),
-            isActive: editor.isActive("heading", { level: 2 }),
-        },
-        {
-            icon: Heading3,
-            title: "标题 3",
-            action: () => editor.chain().focus().toggleHeading({ level: 3 }).run(),
-            isActive: editor.isActive("heading", { level: 3 }),
-        },
-        {
-            divider: true,
-        },
-        {
-            icon: List,
-            title: "无序列表",
-            action: () => editor.chain().focus().toggleBulletList().run(),
-            isActive: editor.isActive("bulletList"),
-        },
-        {
-            icon: ListOrdered,
-            title: "有序列表",
-            action: () => editor.chain().focus().toggleOrderedList().run(),
-            isActive: editor.isActive("orderedList"),
-        },
-        {
-            icon: Quote,
-            title: "引用",
-            action: () => editor.chain().focus().toggleBlockquote().run(),
-            isActive: editor.isActive("blockquote"),
-        },
-        {
-            divider: true,
-        },
-        {
-            icon: Minus,
-            title: "水平分割线",
-            action: () => editor.chain().focus().setHorizontalRule().run(),
-        },
-        {
-            icon: RemoveFormatting,
-            title: "清除格式",
-            action: () => editor.chain().focus().unsetAllMarks().clearNodes().run(),
-        },
-        {
-            divider: true,
-        },
-        {
-            icon: AlignLeft,
-            title: "左对齐",
-            action: () => editor.chain().focus().setTextAlign("left").run(),
-            isActive: editor.isActive({ textAlign: "left" }),
-        },
-        {
-            icon: AlignCenter,
-            title: "居中对齐",
-            action: () => editor.chain().focus().setTextAlign("center").run(),
-            isActive: editor.isActive({ textAlign: "center" }),
-        },
-        {
-            icon: AlignRight,
-            title: "右对齐",
-            action: () => editor.chain().focus().setTextAlign("right").run(),
-            isActive: editor.isActive({ textAlign: "right" }),
-        },
-        {
-            divider: true,
-        },
-        {
-            icon: CheckSquare,
-            title: "任务列表",
-            action: () => editor.chain().focus().toggleTaskList().run(),
-            isActive: editor.isActive("taskList"),
-        },
+    const items: ToolbarItem[] = [
+        { icon: Bold, title: "加粗", action: () => editor.chain().focus().toggleBold().run(), isActive: editor.isActive("bold") },
+        { icon: Italic, title: "斜体", action: () => editor.chain().focus().toggleItalic().run(), isActive: editor.isActive("italic") },
+        { icon: Strikethrough, title: "删除线", action: () => editor.chain().focus().toggleStrike().run(), isActive: editor.isActive("strike") },
+        { icon: Code, title: "行内代码", action: () => editor.chain().focus().toggleCode().run(), isActive: editor.isActive("code") },
+        { icon: SquareCode, title: "代码块", action: () => editor.chain().focus().toggleCodeBlock().run(), isActive: editor.isActive("codeBlock") },
+        { divider: true },
+        { icon: Heading1, title: "标题 1", action: () => editor.chain().focus().toggleHeading({ level: 1 }).run(), isActive: editor.isActive("heading", { level: 1 }) },
+        { icon: Heading2, title: "标题 2", action: () => editor.chain().focus().toggleHeading({ level: 2 }).run(), isActive: editor.isActive("heading", { level: 2 }) },
+        { icon: Heading3, title: "标题 3", action: () => editor.chain().focus().toggleHeading({ level: 3 }).run(), isActive: editor.isActive("heading", { level: 3 }) },
+        { divider: true },
+        { icon: List, title: "无序列表", action: () => editor.chain().focus().toggleBulletList().run(), isActive: editor.isActive("bulletList") },
+        { icon: ListOrdered, title: "有序列表", action: () => editor.chain().focus().toggleOrderedList().run(), isActive: editor.isActive("orderedList") },
+        { icon: Quote, title: "引用", action: () => editor.chain().focus().toggleBlockquote().run(), isActive: editor.isActive("blockquote") },
+        { divider: true },
+        { icon: Minus, title: "分割线", action: () => editor.chain().focus().setHorizontalRule().run() },
+        { icon: RemoveFormatting, title: "清除格式", action: () => editor.chain().focus().unsetAllMarks().clearNodes().run() },
+        { divider: true },
+        { icon: AlignLeft, title: "左对齐", action: () => editor.chain().focus().setTextAlign("left").run(), isActive: editor.isActive({ textAlign: "left" }) },
+        { icon: AlignCenter, title: "居中", action: () => editor.chain().focus().setTextAlign("center").run(), isActive: editor.isActive({ textAlign: "center" }) },
+        { icon: AlignRight, title: "右对齐", action: () => editor.chain().focus().setTextAlign("right").run(), isActive: editor.isActive({ textAlign: "right" }) },
+        { divider: true },
+        { icon: CheckSquare, title: "任务列表", action: () => editor.chain().focus().toggleTaskList().run(), isActive: editor.isActive("taskList") },
         {
             icon: LinkIcon,
             title: "链接",
@@ -168,57 +103,35 @@ export function Toolbar({ editor, onToggleAI, onExport }: ToolbarProps) {
                 if (url) editor.chain().focus().setImage({ src: url }).run();
             },
         },
-        {
-            divider: true,
-        },
-        {
-            icon: Undo,
-            title: "撤销",
-            action: () => editor.chain().focus().undo().run(),
-            disabled: !editor.can().undo(),
-        },
-        {
-            icon: Redo,
-            title: "重做",
-            action: () => editor.chain().focus().redo().run(),
-            disabled: !editor.can().redo(),
-        },
-        {
-            divider: true,
-        },
-        {
-            icon: Sparkles,
-            title: "AI 助手",
-            action: () => onToggleAI?.(),
-        },
-        {
-            icon: FileDown,
-            title: "导出 Markdown",
-            action: () => onExport?.(),
-        },
+        { divider: true },
+        { icon: Undo, title: "撤销", action: () => editor.chain().focus().undo().run(), disabled: !editor.can().undo() },
+        { icon: Redo, title: "重做", action: () => editor.chain().focus().redo().run(), disabled: !editor.can().redo() },
+        { divider: true },
+        { icon: Sparkles, title: "AI 助手", action: () => onToggleAI?.() },
+        { icon: FileDown, title: "导出 Markdown", action: () => onExport?.() },
     ];
 
     return (
-        <div className="flex items-center gap-1 p-1 bg-background/50 backdrop-blur border-b sticky top-0 z-10 overflow-x-auto no-scrollbar">
-            {items.map((item, index) => (
+        <div className="sticky top-0 z-20 -mx-1 mb-2 flex items-center gap-1 overflow-x-auto rounded-xl border border-border/60 bg-background/80 p-1 shadow-[0_1px_0_hsl(var(--border)/0.45),0_10px_20px_hsl(var(--background)/0.24)] backdrop-blur-md no-scrollbar supports-[backdrop-filter]:bg-background/68">
+            {items.map((item, index) =>
                 item.divider ? (
-                    <div key={index} className="w-px h-6 bg-border mx-1" />
+                    <div key={index} className="mx-1 h-6 w-px bg-border/80" />
                 ) : (
                     <button
                         key={index}
                         onClick={item.action}
                         disabled={item.disabled}
                         className={cn(
-                            "p-2 rounded-md transition-colors hover:bg-muted text-muted-foreground hover:text-foreground",
-                            item.isActive && "bg-accent text-accent-foreground",
-                            item.disabled && "opacity-50 cursor-not-allowed"
+                            "inline-flex h-10 w-10 shrink-0 items-center justify-center rounded-lg border border-transparent text-muted-foreground transition-colors hover:bg-muted/70 hover:text-foreground md:h-9 md:w-9",
+                            item.isActive && "border border-border/60 bg-accent text-accent-foreground shadow-sm",
+                            item.disabled && "cursor-not-allowed opacity-50"
                         )}
                         title={item.title}
                     >
                         {item.icon && <item.icon size={16} />}
                     </button>
                 )
-            ))}
+            )}
         </div>
     );
 }
diff --git a/src/components/search-command.tsx b/src/components/search-command.tsx
index 04b5bf1..06a3908 100644
--- a/src/components/search-command.tsx
+++ b/src/components/search-command.tsx
@@ -70,6 +70,11 @@ export function SearchCommand() {
             if (e.key === "k" && (e.metaKey || e.ctrlKey)) {
                 e.preventDefault();
                 setOpen(!isOpen);
+                return;
+            }
+            if (e.key === "Escape" && isOpen) {
+                e.preventDefault();
+                setOpen(false);
             }
         };
 
@@ -97,24 +102,37 @@ export function SearchCommand() {
     if (!isOpen) return null;
 
     return (
-        <div className="fixed inset-0 z-50 flex items-center justify-center bg-background/70 p-4 backdrop-blur-sm animate-in fade-in duration-200">
-            <div className="fixed inset-0" onClick={() => setOpen(false)} />
-            <div className="ui-card relative w-full max-w-lg overflow-hidden shadow-2xl animate-in zoom-in-95 duration-200">
+        <div
+            className="fixed inset-0 z-50 flex items-start justify-center bg-background/70 p-4 pt-[max(1rem,env(safe-area-inset-top))] backdrop-blur-sm animate-in fade-in duration-200 md:items-center"
+            role="dialog"
+            aria-modal="true"
+            aria-label="搜索文档"
+        >
+            <div className="fixed inset-0" onClick={() => setOpen(false)} aria-hidden="true" />
+            <div className="ui-card relative mt-10 w-full max-w-lg overflow-hidden shadow-2xl animate-in zoom-in-95 duration-200 md:mt-0">
                 <Command className="w-full" shouldFilter={false}>
                     <div className="flex items-center border-b border-border/70 px-3">
-                        <Search className="mr-2 h-4 w-4 shrink-0 opacity-50" />
+                        <Search className="mr-2 h-4 w-4 shrink-0 opacity-50" aria-hidden="true" />
                         <Command.Input
                             placeholder="搜索... 支持 tag:项目 type:file updated:7d"
                             value={query}
                             onValueChange={setQuery}
                             className="flex h-12 w-full bg-transparent py-3 text-sm outline-none placeholder:text-muted-foreground"
+                            aria-label="搜索文档输入框"
+                            autoFocus
                         />
                     </div>
                     <div className="border-b border-border/50 px-3 py-2 text-[11px] text-muted-foreground">
                         语法：`tag:标签` `type:file|folder` `updated:7d`
                     </div>
-                    <Command.List className="max-h-[320px] overflow-y-auto p-2">
-                        <Command.Empty className="py-6 text-center text-sm text-muted-foreground">未找到匹配结果</Command.Empty>
+                    <Command.List className="max-h-[55vh] overflow-y-auto p-2 md:max-h-[320px]">
+                        <Command.Empty className="py-8 text-center">
+                            <div className="mx-auto flex h-10 w-10 items-center justify-center rounded-full border border-border/70 bg-muted/35 text-muted-foreground">
+                                <Search size={16} />
+                            </div>
+                            <p className="mt-2 text-sm font-medium text-foreground">未找到匹配结果</p>
+                            <p className="mt-1 text-xs text-muted-foreground">试试更短关键词，或使用 `tag:` `type:` `updated:` 组合筛选</p>
+                        </Command.Empty>
                         <Command.Group heading="文档">
                             {filteredPages.map((page) => (
                                 <Command.Item
diff --git a/src/components/sidebar.tsx b/src/components/sidebar.tsx
index e22098e..36b1e1d 100644
--- a/src/components/sidebar.tsx
+++ b/src/components/sidebar.tsx
@@ -8,6 +8,7 @@ import {
     Sun,
     Moon,
     Upload,
+    Loader2,
     FolderPlus,
     FilePlus,
     Settings,
@@ -20,13 +21,12 @@ import {
     ChevronDown,
     Layers,
     PanelLeftOpen,
-    Plus,
+    SlidersHorizontal,
 } from "lucide-react";
 import { useTheme } from "next-themes";
 import { TreeView } from "./sidebar/tree-view";
 import Link from "next/link";
 import { useRouter } from "next/navigation";
-import { SearchCommand } from "@/components/search-command";
 import { cn, getTagColor } from "@/lib/utils";
 import { useSearchStore } from "@/lib/search-store";
 import { useImport } from "@/components/import-context";
@@ -50,26 +50,20 @@ function RootDropZone() {
         <div
             ref={setNodeRef}
             className={cn(
-                "flex min-h-[50px] flex-1 items-center justify-center rounded-md border-2 border-dashed border-transparent text-xs text-muted-foreground/0 transition-all",
-                "hover:text-muted-foreground/50",
-                isOver && "border-primary/20 bg-accent/30 text-primary/70"
+                "mt-2 flex min-h-[42px] items-center justify-center rounded-lg border border-dashed text-xs transition-all",
+                isOver
+                    ? "border-primary/40 bg-primary/10 text-primary"
+                    : "border-transparent text-muted-foreground/0 hover:border-border/60 hover:text-muted-foreground/70"
             )}
         >
-            {isOver ? "移动到根目录" : ""}
+            {isOver ? "移动到根目录" : "拖拽到此处移到根目录"}
         </div>
     );
 }
 
 export function ResizableSidebar() {
-    const [width, setWidth] = useState(() => {
-        if (typeof window === "undefined") return 256;
-        const savedWidth = localStorage.getItem("sidebar-width");
-        return savedWidth ? parseInt(savedWidth, 10) : 256;
-    });
-    const [isCollapsed, setIsCollapsed] = useState(() => {
-        if (typeof window === "undefined") return false;
-        return localStorage.getItem("sidebar-collapsed") === "true";
-    });
+    const [width, setWidth] = useState(280);
+    const [isCollapsed, setIsCollapsed] = useState(false);
     const [isResizing, setIsResizing] = useState(false);
     const sidebarRef = useRef<HTMLElement>(null);
 
@@ -90,7 +84,7 @@ export function ResizableSidebar() {
         (mouseMoveEvent: MouseEvent) => {
             if (!isResizing) return;
             const newWidth = mouseMoveEvent.clientX;
-            if (newWidth >= 220 && newWidth <= 480) {
+            if (newWidth >= 240 && newWidth <= 500) {
                 setWidth(newWidth);
             }
         },
@@ -110,7 +104,7 @@ export function ResizableSidebar() {
         <aside
             ref={sidebarRef}
             className={cn(
-                "relative z-20 hidden h-screen flex-col border-r bg-secondary md:flex",
+                "group/sidebar relative z-20 hidden h-screen flex-col border-r bg-secondary/80 backdrop-blur-sm md:flex",
                 isResizing ? "transition-none" : "transition-[width] duration-300 ease-in-out",
                 isCollapsed && "w-[0px] border-none"
             )}
@@ -127,7 +121,7 @@ export function ResizableSidebar() {
                 {isCollapsed ? <PanelLeftOpen size={14} /> : <PanelLeftClose size={14} />}
             </button>
 
-            <div className={cn("flex flex-1 flex-col overflow-hidden", isCollapsed ? "hidden" : "visible")}> 
+            <div className={cn("flex flex-1 flex-col overflow-hidden", isCollapsed ? "hidden" : "visible")}>
                 <SidebarContent />
             </div>
 
@@ -142,7 +136,7 @@ export function ResizableSidebar() {
 }
 
 export function SidebarContent({ onCloseMobile }: { onCloseMobile?: () => void }) {
-    const { pages, fetchPages, addPage, isLoading, movePage, reorderPages } = useEditorStore();
+    const { pages, activePageId, fetchPages, addPage, isLoading, movePage, reorderPages } = useEditorStore();
     const { setOpen, openSearchWithTag } = useSearchStore();
     const { triggerImport, isImporting } = useImport();
     const { theme, setTheme } = useTheme();
@@ -150,12 +144,60 @@ export function SidebarContent({ onCloseMobile }: { onCloseMobile?: () => void }
     const [mounted, setMounted] = React.useState(false);
 
     const [isWorkspaceOpen, setIsWorkspaceOpen] = React.useState(true);
-    const [isTagsOpen, setIsTagsOpen] = React.useState(true);
+    const [isFilterOpen, setIsFilterOpen] = React.useState(false);
+    const [expandedMap, setExpandedMap] = React.useState<Record<string, boolean>>(() => {
+        if (typeof window === "undefined") return {};
+        try {
+            const raw = localStorage.getItem("noteai-tree-expanded");
+            if (!raw) return {};
+            const parsed = JSON.parse(raw);
+            if (!parsed || typeof parsed !== "object") return {};
+            return parsed as Record<string, boolean>;
+        } catch {
+            return {};
+        }
+    });
 
     React.useEffect(() => {
         setMounted(true);
     }, []);
 
+    React.useEffect(() => {
+        if (typeof window === "undefined") return;
+        try {
+            localStorage.setItem("noteai-tree-expanded", JSON.stringify(expandedMap));
+        } catch {
+            // ignore storage errors
+        }
+    }, [expandedMap]);
+
+    React.useEffect(() => {
+        if (!activePageId) return;
+        const current = pages.find((p) => p.id === activePageId);
+        if (!current) return;
+
+        const ancestors: string[] = [];
+        let cursor = current.parentId;
+        while (cursor) {
+            ancestors.push(cursor);
+            cursor = pages.find((p) => p.id === cursor)?.parentId ?? null;
+        }
+        if (ancestors.length === 0) return;
+        setExpandedMap((prev) => {
+            const next = { ...prev };
+            ancestors.forEach((id) => {
+                next[id] = true;
+            });
+            return next;
+        });
+    }, [activePageId, pages]);
+
+    const toggleExpand = React.useCallback((id: string) => {
+        setExpandedMap((prev) => ({ ...prev, [id]: !prev[id] }));
+    }, []);
+
+    const allTags = Array.from(new Set(pages.flatMap((p) => p.tags || []))).sort((a, b) => a.localeCompare(b));
+
     const handleLogout = async () => {
         try {
             await fetch("/api/auth/logout", { method: "POST" });
@@ -232,86 +274,129 @@ export function SidebarContent({ onCloseMobile }: { onCloseMobile?: () => void }
     };
 
     return (
-        <div className="flex h-full flex-col bg-secondary">
-            <div className="flex items-center justify-between p-4">
-                <div className="flex cursor-pointer items-center gap-2 font-semibold text-foreground/80 transition-colors hover:text-foreground">
-                    <div className="flex h-6 w-6 items-center justify-center rounded-md bg-primary text-[10px] text-primary-foreground shadow-sm">AI</div>
-                    <span className="tracking-tight">NoteAI</span>
-                </div>
-                <div className="flex items-center gap-1">
-                    <button
-                        onClick={() => addPage(null, "file")}
-                        className="ui-icon-btn h-8 w-8"
-                        title="新建文件"
-                    >
-                        <FilePlus size={16} />
-                    </button>
-                    <button
-                        onClick={() => addPage(null, "folder")}
-                        className="ui-icon-btn h-8 w-8"
-                        title="新建文件夹"
-                    >
-                        <FolderPlus size={16} />
-                    </button>
-                    {onCloseMobile && (
-                        <button
-                            onClick={onCloseMobile}
-                            className="ui-icon-btn h-8 w-8 hover:text-destructive"
-                            title="关闭菜单"
-                        >
-                            <PanelLeftClose size={16} />
+        <div className="flex h-full flex-col">
+            <div className="space-y-3 border-b border-border/60 bg-muted/[0.18] p-3">
+                <div className="flex items-center justify-between">
+                    <div className="flex items-center gap-2">
+                        <div className="flex h-7 w-7 items-center justify-center rounded-md bg-primary text-[10px] font-bold text-primary-foreground">AI</div>
+                        <div>
+                            <div className="text-sm font-semibold tracking-tight text-foreground">NoteAI</div>
+                            <div className="text-[10px] text-muted-foreground">Workspace</div>
+                        </div>
+                    </div>
+                    <div className="flex items-center gap-1">
+                        <button onClick={() => addPage(null, "file")} className="ui-icon-btn h-10 w-10 md:h-8 md:w-8" title="新建文件">
+                            <span className="sr-only">新建文件</span>
+                            <FilePlus size={15} />
                         </button>
-                    )}
+                        <button onClick={() => addPage(null, "folder")} className="ui-icon-btn h-10 w-10 md:h-8 md:w-8" title="新建文件夹">
+                            <span className="sr-only">新建文件夹</span>
+                            <FolderPlus size={15} />
+                        </button>
+                        <button
+                            onClick={() => {
+                                setOpen(true);
+                                handleItemClick();
+                            }}
+                            className="ui-icon-btn h-10 w-10 md:h-8 md:w-8"
+                            title="搜索文档 (Ctrl+K)"
+                            aria-label="搜索文档"
+                        >
+                            <Search size={15} />
+                        </button>
+                        {onCloseMobile && (
+                            <button
+                                onClick={onCloseMobile}
+                                className="ui-icon-btn h-10 w-10 hover:text-destructive md:h-8 md:w-8"
+                                title="关闭菜单"
+                            >
+                                <span className="sr-only">关闭菜单</span>
+                                <PanelLeftClose size={16} />
+                            </button>
+                        )}
+                    </div>
                 </div>
-            </div>
 
-            <div className="mb-4 space-y-1 px-3">
-                <SearchCommand />
                 <button
-                    onClick={() => {
-                        setOpen(true);
-                        handleItemClick();
-                    }}
-                    className="group flex w-full items-center gap-2 rounded-lg px-3 py-2 text-sm font-medium text-muted-foreground transition-colors hover:bg-muted/60"
-                >
-                    <Search size={16} className="group-hover:text-foreground" />
-                    <span className="group-hover:text-foreground">全局搜索</span>
-                    <kbd className="ui-kbd ml-auto">
-                        <span className="text-xs">Ctrl</span>K
-                    </kbd>
-                </button>
-            </div>
-
-            <div className="flex-1 space-y-1 overflow-y-auto px-2">
-                <button
-                    onClick={() => setIsWorkspaceOpen(!isWorkspaceOpen)}
-                    className="group/workspace mb-1 flex w-full items-center justify-between px-2 py-1.5 text-xs font-medium uppercase tracking-wider text-muted-foreground/70 transition-colors hover:text-foreground"
+                    onClick={() => setIsFilterOpen((v) => !v)}
+                    className="flex h-10 w-full items-center justify-between rounded-md px-2 text-xs font-medium text-muted-foreground transition-colors hover:bg-muted/60 hover:text-foreground md:h-8"
                 >
                     <span className="flex items-center gap-1.5">
-                        {isWorkspaceOpen ? <ChevronDown size={12} /> : <ChevronRight size={12} />}
-                        <Layers size={14} className="opacity-70" />
-                        我的工作区
+                        <SlidersHorizontal size={13} />
+                        筛选器
                     </span>
-                    <Plus
-                        size={14}
-                        className="cursor-pointer rounded opacity-0 transition-opacity group-hover/workspace:opacity-100 hover:bg-muted/50"
-                        onClick={(e) => {
-                            e.stopPropagation();
-                            addPage(null, "file");
-                            setIsWorkspaceOpen(true);
-                        }}
-                    />
+                    {isFilterOpen ? <ChevronDown size={14} /> : <ChevronRight size={14} />}
+                </button>
+
+                {isFilterOpen && (
+                    <div className="rounded-lg border border-border/60 bg-background/40 p-2">
+                        <div className="mb-1 flex items-center gap-1 text-[11px] text-muted-foreground">
+                            <TagIcon size={12} />
+                            标签筛选
+                        </div>
+                        <div className="flex max-h-24 flex-wrap gap-1 overflow-y-auto pr-1">
+                            {allTags.length > 0 ? (
+                                allTags.map((tag) => {
+                                    const colors = getTagColor(tag);
+                                    return (
+                                        <button
+                                            key={tag}
+                                            onClick={() => {
+                                                openSearchWithTag(tag);
+                                                setOpen(true);
+                                                handleItemClick();
+                                            }}
+                                            className={cn(
+                                                "inline-flex items-center gap-1 rounded-[4px] border px-2 py-0.5 text-[10px] font-medium shadow-sm transition-transform duration-150 hover:scale-[1.02]",
+                                                colors.bg,
+                                                colors.text,
+                                                colors.border
+                                            )}
+                                            title={`按标签筛选：${tag}`}
+                                        >
+                                            <Hash size={10} className="opacity-70" />
+                                            {tag}
+                                        </button>
+                                    );
+                                })
+                            ) : (
+                                <span className="text-[10px] italic text-muted-foreground/70">暂无标签</span>
+                            )}
+                        </div>
+                    </div>
+                )}
+            </div>
+
+            <div className="flex min-h-0 flex-1 flex-col p-2">
+                <button
+                    onClick={() => setIsWorkspaceOpen(!isWorkspaceOpen)}
+                    className="mb-1 flex h-10 w-full items-center justify-between rounded-lg px-2 text-xs font-semibold uppercase tracking-wider text-muted-foreground transition-colors hover:bg-muted/60 hover:text-foreground md:h-8"
+                >
+                    <span className="flex items-center gap-1.5">
+                        <Layers size={13} className="opacity-80" />
+                        文档
+                        <span className="rounded bg-muted px-1.5 py-0.5 text-[10px] text-muted-foreground">{pages.length}</span>
+                    </span>
+                    {isWorkspaceOpen ? <ChevronDown size={14} /> : <ChevronRight size={14} />}
                 </button>
 
                 {isWorkspaceOpen && (
                     <>
                         {isLoading ? (
-                            <div className="px-4 text-xs text-muted-foreground animate-pulse">加载中...</div>
+                            <div className="space-y-2 px-1 py-2">
+                                <div className="rounded-lg border border-border/50 bg-background/35 p-2">
+                                    <div className="h-4 w-1/3 animate-pulse rounded bg-muted/60" />
+                                    <div className="mt-2 h-7 animate-pulse rounded-md bg-muted/55" />
+                                    <div className="mt-1.5 h-7 animate-pulse rounded-md bg-muted/45" />
+                                    <div className="mt-1.5 h-7 animate-pulse rounded-md bg-muted/35" />
+                                </div>
+                            </div>
                         ) : pages.length === 0 ? (
-                            <div className="px-4 py-8 text-center text-xs text-muted-foreground">
-                                <p className="mb-2">暂无页面</p>
+                            <div className="ui-card mt-2 flex flex-col items-center gap-2 px-3 py-6 text-center text-xs text-muted-foreground">
+                                <FileText size={18} className="text-muted-foreground/70" />
+                                <p>还没有文档</p>
                                 <button onClick={() => addPage(null, "file")} className="text-primary hover:underline">
-                                    新建一个
+                                    新建第一页
                                 </button>
                             </div>
                         ) : (
@@ -321,17 +406,24 @@ export function SidebarContent({ onCloseMobile }: { onCloseMobile?: () => void }
                                 onDragStart={onDragStart}
                                 onDragEnd={handleDragEnd}
                             >
-                                <div onClick={handleItemClick} className="flex min-h-0 flex-1 flex-col">
-                                    <TreeView pages={pages} parentId={null} />
+                                <div
+                                    onClick={handleItemClick}
+                                    className="min-h-0 flex-1 overflow-y-auto rounded-lg bg-background/15 p-0.5 pr-0.5"
+                                >
+                                    <TreeView
+                                        pages={pages}
+                                        parentId={null}
+                                        expanded={expandedMap}
+                                        toggleExpand={toggleExpand}
+                                        folderFileCount={{}}
+                                    />
                                     <RootDropZone />
                                 </div>
                                 <DragOverlay>
                                     {activeDragItem ? (
-                                        <div className="flex items-center gap-2 rounded-md border bg-popover px-2 py-1 text-sm opacity-90 shadow-lg">
+                                        <div className="flex items-center gap-2 rounded-md border bg-popover px-2 py-1 text-sm opacity-95 shadow-lg">
                                             {activeDragItem.icon ? (
-                                                <span className="flex h-4 w-4 items-center justify-center text-[16px] leading-none grayscale-[0.2]">
-                                                    {activeDragItem.icon}
-                                                </span>
+                                                <span className="flex h-4 w-4 items-center justify-center text-[16px] leading-none grayscale-[0.2]">{activeDragItem.icon}</span>
                                             ) : activeDragItem.type === "folder" ? (
                                                 <Folder size={16} className="shrink-0 fill-indigo-500/20 text-indigo-500" />
                                             ) : (
@@ -347,78 +439,46 @@ export function SidebarContent({ onCloseMobile }: { onCloseMobile?: () => void }
                 )}
             </div>
 
-            <div className="border-t border-border/40 px-2 py-2">
-                <button
-                    onClick={() => setIsTagsOpen(!isTagsOpen)}
-                    className="group/tags mb-1 flex w-full items-center justify-between px-2 py-1.5 text-xs font-medium uppercase tracking-wider text-muted-foreground/70 transition-colors hover:text-foreground"
-                >
-                    <span className="flex items-center gap-1.5">
-                        {isTagsOpen ? <ChevronDown size={12} /> : <ChevronRight size={12} />}
-                        <TagIcon size={13} className="opacity-70" />
-                        标签
-                    </span>
-                </button>
-
-                {isTagsOpen && (
-                    <div className="flex flex-wrap gap-1 px-2">
-                        {Array.from(new Set(pages.flatMap((p) => p.tags || []))).map((tag) => {
-                            const colors = getTagColor(tag);
-                            return (
-                                <button
-                                    key={tag}
-                                    onClick={() => {
-                                        openSearchWithTag(tag);
-                                        handleItemClick();
-                                    }}
-                                    className={cn(
-                                        "inline-flex items-center gap-1 rounded-[4px] border px-2.5 py-1 text-[11px] font-medium shadow-sm transition-transform duration-200 hover:scale-105 active:scale-95",
-                                        colors.bg,
-                                        colors.text,
-                                        colors.border
-                                    )}
-                                    title={`按标签筛选：${tag}`}
-                                >
-                                    <Hash size={12} className="opacity-70" />
-                                    {tag}
-                                </button>
-                            );
-                        })}
-                        {pages.flatMap((p) => p.tags || []).length === 0 && (
-                            <span className="px-1 text-[10px] italic text-muted-foreground/60">暂无标签</span>
-                        )}
+            <div className="border-t border-border/60 bg-muted/[0.22] p-3 backdrop-blur-sm">
+                <div className="flex items-center justify-between rounded-xl border border-border/60 bg-background/45 px-2 py-1">
+                    <span className="px-1 text-[11px] text-muted-foreground">系统</span>
+                    <div className="flex items-center gap-1">
+                        <button
+                            onClick={() => triggerImport(null)}
+                            disabled={isImporting}
+                            aria-busy={isImporting}
+                            className="ui-icon-btn h-10 w-10 md:h-8 md:w-8"
+                            title={isImporting ? "导入中..." : "导入"}
+                        >
+                            <span className="sr-only">{isImporting ? "导入中" : "导入"}</span>
+                            {isImporting ? <Loader2 size={15} className="animate-spin" /> : <Upload size={15} />}
+                        </button>
+                        <Link
+                            href="/settings"
+                            onClick={handleItemClick}
+                            className="ui-icon-btn h-10 w-10 md:h-8 md:w-8"
+                            title="设置"
+                            aria-label="设置"
+                        >
+                            <Settings size={15} />
+                        </Link>
+                        <button
+                            onClick={() => setTheme(theme === "dark" ? "light" : "dark")}
+                            className="ui-icon-btn h-10 w-10 md:h-8 md:w-8"
+                            title={mounted ? (theme === "dark" ? "切换到明亮模式" : "切换到暗黑模式") : "切换主题"}
+                        >
+                            <span className="sr-only">{mounted ? (theme === "dark" ? "切换到明亮模式" : "切换到暗黑模式") : "切换主题"}</span>
+                            {mounted ? (theme === "dark" ? <Sun size={15} /> : <Moon size={15} />) : <Moon size={15} />}
+                        </button>
+                        <button
+                            onClick={handleLogout}
+                            className="ui-icon-btn h-10 w-10 hover:text-destructive md:h-8 md:w-8"
+                            title="退出登录"
+                        >
+                            <span className="sr-only">退出登录</span>
+                            <LogOut size={15} />
+                        </button>
                     </div>
-                )}
-            </div>
-
-            <div className="space-y-1 border-t bg-muted/20 p-3 backdrop-blur-sm">
-                <button
-                    onClick={() => triggerImport(null)}
-                    disabled={isImporting}
-                    className="ui-btn-secondary w-full justify-start border border-transparent text-muted-foreground hover:border-border hover:text-foreground disabled:opacity-50"
-                >
-                    <Upload size={16} />
-                    <span>{isImporting ? "导入中..." : "导入文档"}</span>
-                </button>
-
-                <div className="flex items-center gap-1">
-                    <Link
-                        href="/settings"
-                        onClick={handleItemClick}
-                        className="ui-btn-secondary flex-1 justify-start border border-transparent text-muted-foreground hover:border-border hover:text-foreground"
-                    >
-                        <Settings size={16} />
-                        <span>设置</span>
-                    </Link>
-                    <button
-                        onClick={() => setTheme(theme === "dark" ? "light" : "dark")}
-                        className="ui-icon-btn"
-                        title={mounted ? (theme === "dark" ? "切换到明亮模式" : "切换到暗黑模式") : "切换主题"}
-                    >
-                        {mounted ? (theme === "dark" ? <Sun size={16} /> : <Moon size={16} />) : <Moon size={16} />}
-                    </button>
-                    <button onClick={handleLogout} className="ui-icon-btn hover:text-destructive" title="退出登录">
-                        <LogOut size={16} />
-                    </button>
                 </div>
             </div>
         </div>
diff --git a/src/components/sidebar/tree-view.tsx b/src/components/sidebar/tree-view.tsx
index 38357dc..5b37582 100644
--- a/src/components/sidebar/tree-view.tsx
+++ b/src/components/sidebar/tree-view.tsx
@@ -1,6 +1,5 @@
 "use client";
 
-import { useState } from "react";
 import * as DropdownMenu from "@radix-ui/react-dropdown-menu";
 import { useRouter, usePathname } from "next/navigation";
 import { useSortable, SortableContext, verticalListSortingStrategy } from "@dnd-kit/sortable";
@@ -27,7 +26,43 @@ import { useConfirm } from "@/components/confirm-provider";
 interface TreeViewProps {
     pages: Page[];
     parentId: string | null;
+    expanded: Record<string, boolean>;
+    toggleExpand: (id: string) => void;
     level?: number;
+    folderFileCount: Record<string, number>;
+}
+
+function buildFolderFileCount(pages: Page[]): Record<string, number> {
+    const byParent = new Map<string | null, Page[]>();
+    for (const page of pages) {
+        const siblings = byParent.get(page.parentId) || [];
+        siblings.push(page);
+        byParent.set(page.parentId, siblings);
+    }
+
+    const counts: Record<string, number> = {};
+
+    const dfs = (folderId: string): number => {
+        const children = byParent.get(folderId) || [];
+        let total = 0;
+        for (const child of children) {
+            if (child.type === "file") {
+                total += 1;
+            } else {
+                total += dfs(child.id);
+            }
+        }
+        counts[folderId] = total;
+        return total;
+    };
+
+    for (const page of pages) {
+        if (page.type === "folder") {
+            dfs(page.id);
+        }
+    }
+
+    return counts;
 }
 
 function TreeNode({
@@ -36,12 +71,14 @@ function TreeNode({
     level,
     expanded,
     toggleExpand,
+    folderFileCount,
 }: {
     node: Page;
     pages: Page[];
     level: number;
     expanded: Record<string, boolean>;
     toggleExpand: (id: string) => void;
+    folderFileCount: Record<string, number>;
 }) {
     const { activePageId, setActivePageId, addPage, deletePage } = useEditorStore();
     const router = useRouter();
@@ -52,6 +89,7 @@ function TreeNode({
     const isFolder = node.type === "folder";
     const hasChildren = pages.some((p) => p.parentId === node.id);
     const isExpanded = expanded[node.id];
+    const isActive = activePageId === node.id;
 
     const { attributes, listeners, setNodeRef, transform, transition, isDragging } = useSortable({
         id: node.id,
@@ -59,7 +97,7 @@ function TreeNode({
     });
 
     const style = {
-        paddingLeft: `${level * 12 + 8}px`,
+        paddingLeft: `${level * 12 + 6}px`,
         transform: CSS.Translate.toString(transform),
         transition,
         opacity: isDragging ? 0.5 : 1,
@@ -69,17 +107,19 @@ function TreeNode({
         <div key={node.id} style={style} ref={setNodeRef} {...attributes} {...listeners}>
             <div
                 className={cn(
-                    "group flex items-center justify-between px-2 py-1 text-sm rounded-md transition-colors cursor-pointer select-none border border-transparent",
-                    activePageId === node.id
-                        ? "bg-accent text-accent-foreground font-medium"
-                        : "text-muted-foreground hover:bg-muted/50 hover:text-foreground"
+                    "group relative flex h-10 items-center justify-between rounded-lg border border-transparent px-1.5 text-[13px] transition-colors cursor-pointer select-none md:h-8",
+                    isActive
+                        ? "border-border/60 bg-accent/75 text-accent-foreground"
+                        : "text-muted-foreground hover:border-border/45 hover:bg-muted/55 hover:text-foreground"
                 )}
                 onClick={() => {
                     setActivePageId(node.id);
                     if (pathname !== "/") router.push("/");
                 }}
             >
-                <div className="flex items-center gap-1.5 flex-1 min-w-0">
+                {isActive && <span className="absolute left-0 top-[8px] h-5 w-0.5 rounded-r bg-primary/90" />}
+
+                <div className="grid min-w-0 flex-1 grid-cols-[1.75rem_1.25rem_minmax(0,1fr)] items-center gap-1.5">
                     <button
                         onPointerDown={(e) => e.stopPropagation()}
                         onClick={(e) => {
@@ -87,36 +127,42 @@ function TreeNode({
                             toggleExpand(node.id);
                         }}
                         className={cn(
-                            "p-0.5 rounded-sm hover:bg-muted-foreground/20 transition-colors",
+                            "flex h-7 w-7 items-center justify-center rounded-md text-muted-foreground/70 transition-colors hover:bg-muted-foreground/15 hover:text-foreground md:h-6 md:w-6",
                             !hasChildren && !isFolder && "invisible"
                         )}
                     >
-                        <ChevronRight
-                            size={16}
-                            className={cn("transition-transform shrink-0 text-muted-foreground/50", isExpanded && "rotate-90")}
-                        />
+                        <ChevronRight size={14} className={cn("shrink-0 text-muted-foreground/60 transition-transform", isExpanded && "rotate-90")} />
                     </button>
-                    {node.icon ? (
-                        <span className="text-[16px] leading-none shrink-0 w-4 h-4 flex items-center justify-center grayscale-[0.2]">{node.icon}</span>
-                    ) : isFolder ? (
-                        isExpanded ? (
-                            <FolderOpen size={16} className="text-indigo-500 fill-indigo-500/20 shrink-0" />
+                    <span className="flex h-5 w-5 items-center justify-center">
+                        {node.icon ? (
+                            <span className="flex h-5 w-5 items-center justify-center text-[16px] leading-none grayscale-[0.2]">{node.icon}</span>
+                        ) : isFolder ? (
+                            isExpanded ? (
+                                <FolderOpen size={15} className="fill-indigo-500/20 text-indigo-500" />
+                            ) : (
+                                <Folder size={15} className="fill-indigo-500/20 text-indigo-500" />
+                            )
                         ) : (
-                            <Folder size={16} className="text-indigo-500 fill-indigo-500/20 shrink-0" />
-                        )
-                    ) : (
-                        <FileText size={16} className="text-muted-foreground/70 shrink-0" />
-                    )}
-                    <span className="truncate text-[14px] leading-none mb-0.5">{node.title}</span>
+                            <FileText size={15} className="text-muted-foreground/70" />
+                        )}
+                    </span>
+                    <span className="flex min-w-0 items-center gap-1.5">
+                        <span className="truncate">{node.title || "无标题"}</span>
+                        {isFolder && (
+                            <span className="inline-flex min-w-[1.2rem] shrink-0 items-center justify-center rounded-full bg-muted px-1.5 py-0.5 text-[10px] font-medium text-muted-foreground">
+                                {folderFileCount[node.id] ?? 0}
+                            </span>
+                        )}
+                    </span>
                 </div>
 
                 <DropdownMenu.Root>
                     <DropdownMenu.Trigger asChild>
                         <button
                             onPointerDown={(e) => e.stopPropagation()}
-                            className="opacity-100 lg:opacity-0 lg:group-hover:opacity-100 p-1 hover:bg-muted-foreground/20 rounded text-muted-foreground transition-opacity"
+                            className="flex h-7 w-7 items-center justify-center rounded-md text-muted-foreground/75 transition-opacity hover:bg-muted-foreground/15 hover:text-foreground opacity-100 md:h-6 md:w-6 lg:opacity-0 lg:group-hover:opacity-100"
                         >
-                            <MoreHorizontal size={14} />
+                            <MoreHorizontal size={13} />
                         </button>
                     </DropdownMenu.Trigger>
                     <DropdownMenu.Portal>
@@ -173,7 +219,7 @@ function TreeNode({
                                 <Download size={14} />
                                 <span>导出</span>
                             </DropdownMenu.Item>
-                            <DropdownMenu.Separator className="h-px bg-muted my-1" />
+                            <DropdownMenu.Separator className="my-1 h-px bg-muted" />
                             <DropdownMenu.Item
                                 className="flex cursor-pointer items-center gap-2 rounded-md px-2 py-1.5 text-sm text-destructive outline-none transition-colors hover:bg-destructive/10"
                                 onClick={async (e) => {
@@ -199,23 +245,25 @@ function TreeNode({
             </div>
 
             {(isExpanded || hasChildren) && isExpanded && (
-                <TreeView pages={pages} parentId={node.id} level={level + 1} />
+                <TreeView
+                    pages={pages}
+                    parentId={node.id}
+                    level={level + 1}
+                    expanded={expanded}
+                    toggleExpand={toggleExpand}
+                    folderFileCount={folderFileCount}
+                />
             )}
         </div>
     );
 }
 
-export function TreeView({ pages, parentId, level = 0 }: TreeViewProps) {
+export function TreeView({ pages, parentId, expanded, toggleExpand, level = 0, folderFileCount }: TreeViewProps) {
+    const computedFolderFileCount = level === 0 ? buildFolderFileCount(pages) : folderFileCount;
     const nodes = pages
         .filter((p) => p.parentId === parentId)
         .sort((a, b) => (a.order || 0) - (b.order || 0));
 
-    const [expanded, setExpanded] = useState<Record<string, boolean>>({});
-
-    const toggleExpand = (id: string) => {
-        setExpanded((prev) => ({ ...prev, [id]: !prev[id] }));
-    };
-
     if (nodes.length === 0) return null;
 
     return (
@@ -229,6 +277,7 @@ export function TreeView({ pages, parentId, level = 0 }: TreeViewProps) {
                         level={level}
                         expanded={expanded}
                         toggleExpand={toggleExpand}
+                        folderFileCount={computedFolderFileCount}
                     />
                 ))}
             </div>
diff --git a/src/lib/store.ts b/src/lib/store.ts
index f1549d9..b35ce33 100644
--- a/src/lib/store.ts
+++ b/src/lib/store.ts
@@ -109,7 +109,8 @@ export const useEditorStore = create<EditorState>()(
                         body: JSON.stringify(data),
                     });
                     if (!res.ok) {
-                        throw new Error(`Update failed: ${res.status}`);
+                        const errorText = await res.text().catch(() => "");
+                        throw new Error(`Update failed: ${res.status}${errorText ? ` - ${errorText}` : ""}`);
                     }
                 } catch (e) {
                     console.error("Failed to update page", e);