console 命令行工具 X clear

console

<div class="a">
  <div class="b"></div>
</div>

.a {
  /* position: relative; */
  width: 100px;
  height: 100px;
  border: 1px solid red;
  overflow: hidden;
}
.b {
  position: absolute;
  width: 50px;
  height: 200px;
  border: 1px solid blue;
}