JSFiddle - React, Tailwind, and code Playground

HTML

<div class="boxContent">
  This is the content
</div>
<div class="button">CLick me</div>

CSS

.boxContent{background:red;width:500px;height:400px;border-bottom:1px solid green;display:none}
.button{background:green;width:100px;height:30px;}

JavaScript

var button = $('.button'),
    content = $('.boxContent');

button.on('click',function(){
    content.slideToggle(500);

});