JSFiddle - React, Tailwind, and code Playground

HTML

<div class="shadow"></div>

CSS

div {
    background: #eee;
    border: 10px solid #fff;
    height: 150px;
    margin: 50px;
    width: 200px;
}

/* Shadow */

.shadow {
    box-shadow: 0 1px 5px hsla(0,0%,0%,.25),
                inset 0 0 50px hsla(0,0%,0%,.05);
    position: relative;
}
.shadow:after,
.shadow:before {
    bottom: 7px;
    box-shadow: 0 10px 15px hsla(0,0%,0%,.25);
    content: '';
    height: 50%;
    left: 7px;
    max-width: 300px;
    position: absolute;
    right: 7px;
    z-index: -1;
    -webkit-transform: skew(-15deg) rotate(-8deg);
       -moz-transform: skew(-15deg) rotate(-6deg);
        -ms-transform: skew(-15deg) rotate(-6deg);
         -o-transform: skew(-15deg) rotate(-6deg);
            transform: skew(-15deg) rotate(-6deg);
}
.shadow:after {
    -webkit-transform: skew(15deg) rotate(8deg);
       -moz-transform: skew(15deg) rotate(6deg);
        -ms-transform: skew(15deg) rotate(6deg);
         -o-transform: skew(15deg) rotate(6deg);
            transform: skew(15deg) rotate(6deg);
}