<template>
  <div class="hello">
    <div class="top">3楼</div>
    <div class="middle" :style="display">
      <div class="bedroom room">2楼卧室</div>
      <div class="bathroom room">2楼洗手间</div>
    </div>
    <div class="bottom">Floor 3</div>
    <input type="button" @click="toggle()" value="切换">
  </div>
</template>

<script>
export default {
  name: "HelloWorld",
  data() {
    return {
      display: ""
    };
  },
  methods: {
    toggle() {
      if (this.display === "display:none") {
        this.display = "";
      } else {
        this.display = "display:none";
      }
    }
  }
};
</script>

<style scoped>
/*  ...   */
.bedroom {
 /*  ...   */
  display: block;
}
/*  ...   */

</style>