SOURCE

console 命令行工具 X clear

                    
>
console
.blue {
  background-color: blue;
  width: 100px;
  height: 100px;
}

.red {
  background-color: red;
  width: 100px;
  height: 100px;
  position: relative;
  top: -50px;
  left: 50px;
}
<div class="blue">
</div>
<div class="red">
</div>