function init() { 'use strict' function select(a) { return document.querySelector(a); } var randomNum = Math.floor((Math.random() * 24) + 1), triangle = select('.triangle img'), circle = select('.circle img'), cross = select('.cross img'), box = select('.box img'), link = 'http://kapilnemo.free.fr/codepen/playstation-loading/', order = [ [1,2,3,4], [1,2,4,3], [1,3,2,4], [1,3,4,2], [1,4,2,3], [1,4,3,2], [2,1,3,4], [2,1,4,3], [2,3,1,4], [2,3,4,1], [2,4,1,3], [2,4,3,1], [3,1,2,4], [3,1,4,2], [3,2,1,4], [3,2,4,1], [3,4,1,2], [3,4,2,1], [4,1,2,3], [4,1,3,2], [4,2,1,3], [4,2,3,1], [4,3,1,2], [4,3,2,1] ]; triangle.src = link + order[randomNum][0] + ".png"; circle.src = link + order[randomNum][1] + ".png"; cross.src = link + order[randomNum][2] + ".png"; box.src = link + order[randomNum][3] + ".png"; } window.setInterval(init, 2000);