修复无限画布标题栏与左侧工具栏重叠

app/canvas/[id]/page.tsx

@@ -480,7 +480,7 @@ export default function CanvasEditorPage({ params }: PageProps) {
         </div>
 
         {/* 2. Floating Header (Top Left) */}
-        <div className="absolute top-4 left-4 z-20 flex items-center gap-2 bg-background/80 backdrop-blur-md border rounded-xl p-1.5 shadow-sm">
+        <div className="absolute top-4 left-[5.5rem] z-20 flex items-center gap-2 bg-background/80 backdrop-blur-md border rounded-xl p-1.5 shadow-sm">
            <Tooltip>
              <TooltipTrigger asChild>
                <Button variant="ghost" size="icon" onClick={() => router.push('/')} className="rounded-lg h-8 w-8">