console 命令行工具 X clear

console

<div class="box"> 
  <div class="item">1</div>
  <div class="item">2</div>
  <div class="item">3</div>
</div>

.box {
  width: 600px;
  height: 600px;
  background: red;
  display: flex;
  flex-direction: column;
  align-items:center;
  justify-content:center;
}
.item {
  width: 100px;
  height: 100px;
  background: blue;
}