style: remove card wrapper from error page

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/frontend/src/routes/+error.svelte

@@ -2,7 +2,6 @@
   import { _ } from "svelte-i18n";
   import { page } from "$app/state";
   import { Button } from "$lib/components/ui/button";
-  import { Card, CardContent } from "$lib/components/ui/card";
   import PeonyIcon from "$lib/components/icon/peony-icon.svelte";
   import PeonyBackground from "$lib/components/background/peony-background.svelte";
   import Meta from "$lib/components/meta/meta.svelte";
@@ -21,11 +20,7 @@
   <!-- Content -->
   <div class="relative z-10 container mx-auto px-4 text-center">
     <div class="max-w-2xl mx-auto">
-      <!-- Premium Glassmorphism Card -->
-      <Card
-        class="bg-gradient-to-br from-card/25 via-card/30 to-card/20 backdrop-blur-2xl shadow-2xl shadow-primary/20"
-      >
-        <CardContent class="p-12">
+      <div class="py-12">
           <!-- 404 Animation -->
           <div class="mb-8">
             <div
@@ -92,8 +87,7 @@
               >
             </div>
           </div>
-        </CardContent>
-      </Card>
+      </div>
     </div>
   </div>