JSFiddle - React, Tailwind, and code Playground

HTML

<div class="div1"></div>
<div class="div2"></div>

CSS

.div1 {
    z-index: 99;
}

.div2 {
    z-index: 100;
}

div {
    float: left;
    width: 100px;
    height: 100px;
    border: 1px solid #999;
    background-color: white;
    margin-right: 5px;
    
    -webkit-box-shadow: 0px 0px 80px #A0A0A0;
    -moz-box-shadow: 0px 0px 80px #A0A0A0;
    box-shadow: 0px 0px 80px #A0A0A0;
}