JSFiddle - React, Tailwind, and code Playground

HTML

<div></div>

CSS

div{
    position: relative;
    height: 250px;
    width: 500px;
    background: rgb(240,240,240);
    margin: 0 auto;
}

div:after{
    content: '';
    position: absolute;
    width:20px;
    height: 15px;
    left: 9px;
    bottom: 22px;
    transform: rotate(5deg);
    z-index: -1;
    box-shadow: 0 20px 10px rgba(0,0,0,.5),
                18px 20px 10px rgba(0,0,0,.45),
                36px 20px 10px rgba(0,0,0,.4),
                54px 20px 10px rgba(0,0,0,.35),
                72px 20px 10px rgba(0,0,0,.3),
                90px 20px 10px rgba(0,0,0,.25),
                108px 20px 10px rgba(0,0,0,.2),
                126px 20px 10px rgba(0,0,0,.15),
                144px 20px 10px rgba(0,0,0,.1),
                162px 20px 10px rgba(0,0,0,.05);    
}
div:before{
    content: '';
    position: absolute;
    width:20px;
    height: 15px;
    right: 9px;
    bottom: 22px;
    transform: rotate(-5deg);
    z-index: -1;
    box-shadow: 0 20px 10px rgba(0,0,0,.5),
                -18px 20px 10px rgba(0,0,0,.45),
                -36px 20px 10px rgba(0,0,0,.4),
                -54px 20px 10px rgba(0,0,0,.35),
                -72px 20px 10px rgba(0,0,0,.3),
                -90px 20px 10px rgba(0,0,0,.25),
                -108px 20px 10px rgba(0,0,0,.2),
                -126px 20px 10px rgba(0,0,0,.15),
                -144px 20px 10px rgba(0,0,0,.1),
                -162px 20px 10px rgba(0,0,0,.05);    
}