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console 命令行工具 X clear

                    
>
console
<div class="father">
  <div class="child">
    <p><span>哈哈</span></p>
    <p><span>呵呵</span></p>
  </div>
</div>
.father{
  border: 1px solid #777;
  width: 100px;
  height: 100px;
  text-align: center;
  display: table;
  .child{
    display: table-cell;
    vertical-align: middle;
  }
}