JSFiddle - React, Tailwind, and code Playground

HTML

<button id="toggle-shadow">
  Toogle shadow
</button>
<div id="fields">
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
    <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
    <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
    <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
    <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
    <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
    <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
    <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
    <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
    <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
    <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
    <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
    <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
  <div class="field"></div>
    <div class="field"></div>
  <div class="field"></div>
  <div...

CSS

#fields {
  width: 500px;
  height: 500px;
}

.field {
  width: 10%;
  height: 10%;
  overflow: hidden;
  float: left;
  text-align: center;
  color: #ccc;
  position: relative;
  cursor: pointer;
  background: #fff;
}

.field:hover {
  box-shadow: inset 0px 0px 100px 0px rgba(255, 0, 0, 0.3) !important;
}

JavaScript

jQuery(function() {
  jQuery("#toggle-shadow").click(function() {
    jQuery('.field').each(function() {
    	if(jQuery(this).css("box-shadow") == 'none') {
      	jQuery(this).css("box-shadow", "inset 0px 0px 100px 0px rgba(0, 0, 0, 0.3)");
      } else jQuery(this).css("box-shadow", "none"); 
    });
  });
});