JSFiddle - React, Tailwind, and code Playground

HTML

<div id="change-me" class="green-background">
<button onclick="changeBackground()">Change color</button>
</div>

CSS

.green-background {
  background: green;
}

.blue-background {
  background: blue;
}

JavaScript

const changeBackground = () => {
	if (document.getElementById("change-me").classList.contains("green-background")) {
		document.getElementById("change-me").className = "blue-background"
 	}
  else {
  	document.getElementById("change-me").className = "green-background"
 }
}