<template>  <div class="theme-change">      <button        class="switch"        @click="toggleTheme"        role="switch"        aria-label="切换暗色主题"        :class="{          k: isDark        }"      >        按钮      </button>  </div></template><script setup lang="ts">const isDark = useDark();function toggleTheme() {  isDark.value = isDark.value ? false : true;}</script><style scoped lang="scss">.theme-change {  .switch {    transition: all 3s;    background: green;  }}.k.switch {  background: red;}</style>

// const isDark = useDark();const isDark = ref(false);

// const isDark = useDark();const isDark = ref(false);function toggleTheme() {  document.documentElement.classList.toggle('dark')  isDark.value = isDark.value ? false : true;}