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console 命令行工具 X clear

                    
>
console
<div class="box">
  <div class="a"></div>
  <div class="a"></div>
  <div class="a"></div>
  <div class="a"></div>
</div>
.a {
  width: 20px;
  height: 20px;
  margin-right: 10px;
  background: red;
  position: relative;
}

.a::after {
  content: 'xxx';
  position: absolute;
  top: -20px;
}

.box {
  display: flex;
  border: 1px solid black;
  overflow-x: auto;
}