JSFiddle - React, Tailwind, and code Playground

HTML

<div class="glowable"></div>

CSS

.glowable {
  width: 50px;
  height: 50px;
  border: solid 1px gray;
  margin: 20px;
  transition: all 200ms ease-out;
}
.glow {
  box-shadow: 0 0 6px rgba(35, 173, 255, 1);
}

JavaScript

(function(){
  var glowInterval = 1000
  setInterval(function(){
    $('.glowable').toggleClass('glow')
  }, glowInterval)
})()