JSFiddle - React, Tailwind, and code Playground

HTML

<button onclick="openTest()">Try it</button>

<div id="test">

</div>

CSS

#test {
  width: 500px;
  height: 500px;
  background-color: lightblue;
}

JavaScript

document.getElementById("test").style.display = "none";
 
window.openTest = function() {
  document.getElementById("test").style.display = "block";
}