refactor: use nuxt compatiable 4 folder

app/components/common/DarkToggle.vue

@@ -0,0 +1,25 @@
+<script setup lang="ts">
+const color = useColorMode()
+
+useHead({
+  meta: [{
+    id: 'theme-color',
+    name: 'theme-color',
+    content: () => color.value === 'dark' ? '#222222' : '#ffffff',
+  }],
+})
+
+function toggleDark() {
+  color.preference = color.value === 'dark' ? 'light' : 'dark'
+}
+</script>
+
+<template>
+  <YlfIconButton
+    class="icon-btn hover:text-yellow-400 !outline-none"
+    text-xl
+    title="切换" @click="toggleDark()"
+  >
+    <div i="ri-sun-line dark:ri-moon-line" />
+  </YlfIconButton>
+</template>