JSFiddle - React, Tailwind, and code Playground

HTML

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

CSS

#div1 {
  width: 60px;
  height: 40px;
  background-color: #333;
  margin-right: 10px;
  position: relative;
}
#div2 {
  position: absolute;
  top: 40px;
  left: 0;
  height: 100px;
  width: 60px;
  background-color: #fec000;
  display: none;
}

JavaScript

$('#div1').click(function(hej) {
   $('#div2').slideToggle('fast');
});