console 命令行工具 X clear

console

<div class="box"></div>

.box {
  width: 0;
  height: 0;
  /* background-color: #000; */
  border-top: 0 solid transparent;
  border-right: 0 solid skyblue;
  border-bottom: 100px solid red;
  border-left: 30px solid transparent;
}