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console 命令行工具 X clear

                    
>
console
<div class="thinner-border"></div>
.thinner-border {
    position: relative;
    height: 100px;
    /* border: 1px solid red; */
    /* background: red; */
}

.thinner-border:before {
    content: '';
    position: absolute;
    width: 200%;
    height: 200%;
    border: 1px solid #000;
    transform-origin: 0 0;
    transform: scale(0.5, 0.5);
    box-sizing: border-box;
}