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                    <script src="[email protected]"></script> 
<div id="app">
      <!-- mouse events -->
      <!-- 引数を渡さない場合 -->
      <div class="box" v-on:mouseover="handleEvent">mouseover (enter)</div>
      <!-- 引数を渡す場合 -->
      <div class="box" @mouseleave="handleEvent($event, 5)">mouseleave</div>
      <div class="box" @dblclick="handleEvent">double click</div>
      <div class="box" @mousemove="handleMousemove">
        mouse move <br />position - x:{{ x }}, y {{ y }}


                      .box {
        padding: 100px 50px;
        width: 200px;
        background-color: #ddd;
        text-align: center;
        margin: 20px;
        display: inline-block;
      .bg-red {
        background-color: red;


                const app = Vue.createApp({
  // data, functions
  data() {
    return {
      x: 0, // mousemove用
      y: 0, // mousemove用
  methods: {
    // 第一引数にevent情報、第二引数にオプショナルなデータを受け取る
    // eにevent情報が格納されている
    handleEvent(e, data) {'bg-red');
      console.log(e, e.type);
      if (data) {
    handleMousemove(e) {
      // offsetはeの情報をコンソールで確認できる
      this.x = e.offsetX;
      this.y = e.offsetY;

// mountで指定した範囲内でしかvueは動かない