JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://github.com/arieh/SimpleCounter/raw/master/Source/SimpleCounter.js"></script>
<div id='res' class='decr'></div>

CSS

.decr{color:red}

.incr{color:blue}

JavaScript

var counter = new SimpleCounter('res',(new Date())/1000+10,{'continue':false});
counter.addEvent('done',function(){
    $('res').removeClass('decr').addClass('incr');
});