SOURCE

console 命令行工具 X clear

                    
>
console
<div class="c">
	abcd
</div>
.c {
    position: absolute;
    left: 0;
    top: 0;
    right: 0;
    bottom: 0;
    width: 50px;
    height: 30px;
    margin: auto;
    background: #F00;
}