JSFiddle - React, Tailwind, and code Playground

HTML

<div >Div
<div class="abc">
</div>
</div>

CSS

.class1{
    color:red;
}

.class2{
    color:blue;
}

.class3{
    color:grey;
}

JavaScript

var counter = 1,
    int = setInterval(function(){
    $("div").attr("class", "class" + counter);
    var c = 3;
    if($("div").find(".abc")){
    	c = 1; 
    }else{ c = 2;}
    if (counter === 3){
        counter = 1;
        
    } else {
        counter++;
    }
}, 1000);