JSFiddle - React, Tailwind, and code Playground

HTML

<div id="reviews">
        <div>
            1
        </div>
        <div>
            2
        </div>
        <div>
            3
        </div>
        <div>
            4
        </div>
        <div>
            5
        </div>
</div>

CSS

#item-n{
  color: #ff0000;
}
#item-m{
  color: #0000ff;
}

JavaScript

var count = 2;
var i = 20;

$('#reviews div').each(function() {
    count += 3;
		if (count >= "5") {
			this.setAttribute("class","item-"+count);
		}
    else {
    	this.setAttribute("class","item-"+i);
    }
});