feat(module): refresh playground style and dark mode

packages/module/playground/app.vue

@@ -1,11 +1,38 @@
-<script setup>
+<script setup lang="ts">
+import { MoonIcon, SunIcon } from '@radix-icons/vue'
+
+const isDark = ref(true)
+useHead({ htmlAttrs: { class: () => isDark.value ? 'dark' : '' } })
 </script>
 
 <template>
-  <div>
-    <UiButton :variant="'destructive'">
-      hi
-    </UiButton>
-    Nuxt module playground!
-  </div>
+  <main class="flex flex-col min-h-dvh">
+    <header class="border-b py-1 ">
+      <div class="container flex justify-between items-center ">
+        <h1 class="font-medium">
+          shadcn-vue Playground
+        </h1>
+
+        <ClientOnly>
+          <button
+            class="p-2 hover:bg-gray-200 dark:hover:bg-gray-700 transition-colors rounded-md"
+            aria-label="Toggle dark mode"
+            @click="isDark = !isDark"
+          >
+            <component
+              :is="isDark ? SunIcon : MoonIcon"
+              class="size-5"
+            />
+          </button>
+        </ClientOnly>
+      </div>
+    </header>
+
+    <!-- Try your components here -->
+    <section class="container grow my-4 p-4 rounded-md border grid place-content-center">
+      <UiButton variant="destructive">
+        Hi
+      </UiButton>
+    </section>
+  </main>
 </template>