JSFiddle - React, Tailwind, and code Playground

by Softlink

HTML

<div class="block"></div>

CSS

.block{
    width: 300px;
    height: 300px;
    margin: 50px auto;
    position: relative;
    border: 2px solid #aaaa00;
    background: #fff;
    border-radius: 10px;
}

.block:before, .block:after{
    content:'';
    position: absolute;
    bottom: 5px;
    width: 50%;
    height: 40px;
    box-shadow: 0px 10px 20px 0px rgba(0,0,0,0.6);
    border-radius: 5px;
    z-index: -1;
}

.block:after{
    right: 3px;
    -webkit-transform: rotate(3deg);
    -moz-transform: rotate(3deg);
    -o-transform: rotate(3deg);
    -ms-transform: rotate(3deg);
    transform: rotate(3deg);
}

.block:before{
    left: 3px;
    -webkit-transform: rotate(-3deg);
    -moz-transform: rotate(-3deg);
    -o-transform: rotate(-3deg);
    -ms-transform: rotate(-3deg);
    transform: rotate(-3deg);
}