JSFiddle - React, Tailwind, and code Playground

HTML

<div class="bulb"> </div>
<div class="bulb"> </div>
<div class="bulb"> </div>

CSS

.bulb {
    width: 50px;
    height: 100px;
    border: 2px #000 solid;
    float: left;
    margin: 10px;
}
.bulb.on {
    background: #ff0;
}

JavaScript

var timer;
function light ( i ) {
    i = i % $(".bulb").length;
    $(".bulb").eq(i).addClass("on").siblings().removeClass("on");
    timer = setTimeout(function(){
        light( ++i );
    }, 1000);
}
$(document).ready( function() {
    light(0);
});