div加入滚动条

https://www.runoob.com/w3cnote/div-scroll.html

  <div style="overflow: hidden auto; height: calc(60vh - 227px);">
    <el-button @click="btn1">点击1</el-button>
    <el-button @click="btn2">点击2</el-button>
    111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />
    111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />
    111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />
    111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />111<br />
  </div>

https://www.zhihu.com/tardis/bd/art/617143133?source_id=1001

<el-scrollbar height="400px">
    <p v-for="item in 20" :key="item" class="scrollbar-demo-item">{{ item }}</p >
  </el-scrollbar>