JSFiddle - React, Tailwind, and code Playground

HTML

<a href="#" class="divblock"></a>

CSS

.divblock {
    display: block;
    height: 400px;
    width: 400px;
    background-color: grey;
    margin: 20px auto;
}

.glowBlock {
    box-shadow: 0 0 5px 5px #ccc;
}

JavaScript

$(document).ready(function () {
    $(".divblock").mouseover(function () {
      $(this).addClass("glowBlock");     
    });
    
    $(".divblock").mouseout(function () {
      $(this).removeClass("glowBlock");     
    });
});