JSFiddle - React, Tailwind, and code Playground

HTML

<div id="test" height="200px" class="backgroundA"> div test 1
    </div>

 <div id="test2" name="test2" height="200px" class="backgroundB"> div test2
    </div>


<input type="button" id="btn" />

CSS

.backgroundA {
    background-image:...

JavaScript

function change()
{
    if (document.getElementById("test").className =="backgroundA")
    {
        document.getElementById("test").className="backgroundB";
    document.getElementById("test2").className="backgroundA";
    }
    else
    {
        document.getElementById("test").className="backgroundA";
    document.getElementById("test2").className="backgroundB";
    
    }
}

btn.onclick= change;