JSFiddle - React, Tailwind, and code Playground
HTML
<div id="test"></div>
CSS
#test
{
width: 200px;
height: 200px;
}
#test:before
{
content: url(http://placehold.it/200x200);
position: relative;
top: -100%;
left: 0px;
}
#test.test:before {
top: 0%;
}
JavaScript
var test = document.getElementById("test");
var span = document.getElementById("change");
setInterval(function(){
test.className = test.className.indexOf("test") >= 0
? test.className.replace("test", "").replace(" ", " ").trim()
: (test.className + " test").trim();
},3000);