JSFiddle - React, Tailwind, and code Playground

HTML

<img id="bg" />

JavaScript

var imgs = [ 
'http://www.google.com/logos/2011/firstmaninspace11-hp.jpg', 
'http://l.yimg.com/a/i/ww/met/logo/20100909/yahoo_logo_fr.png', 
'http://images.apple.com/euro/home/images/ipad2_hero2_20110302.png' 
]; 
var n = imgs.length; 
var currIndex = Math.floor(Math.random()*n); 

var bgEl = document.getElementById('bg');
bgEl.src = imgs[currIndex];