重构大量文件

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 { FileDown, Hash, X, Plus, ChevronLeft, ChevronRight, Sparkles, Lock, Unlock } from "lucide-react";
+import { Hash, X, Plus, ChevronLeft, ChevronRight, Sparkles, Lock, Unlock } from "lucide-react";
 import { useSettingsStore } from "@/lib/settings-store";
 import { exportPageAsMarkdown } from "@/lib/export";
 import { useState } from "react";
@@ -46,14 +46,6 @@ export default function Home() {
             <div className="flex-1 overflow-y-auto scroll-smooth">
               <div className="max-w-7xl mx-auto px-4 md:px-16 py-6 min-h-screen content-start">
 
-                {/* Mobile Back Button */}
-                <div className="md:hidden mb-4 flex items-center text-muted-foreground" onClick={() => updatePage(null as any, {} as any)}>
-                  {/* Note: updatePage isn't the right way to clear selection. We need setPageId(null). 
-                     But store only exposes updatePage. Let's fix store usage or use a store action if available.
-                     Actually, looking at store.ts, we need `setActivePageId`.
-                 */}
-                </div>
-
                 <div className="group mb-8 relative">
                   {/* Mobile Back Button Integration in Header */}
                   <div className="md:hidden absolute -top-12 left-0 flex items-center gap-1 py-2 text-muted-foreground hover:text-foreground cursor-pointer"