"use strict"; var file, scripts = document.getelementsbytagname("script"); file = scripts[scripts.length - 1].getattribute("src"); var rgba = getquerystring('rgba', file); console.log(rgba); function getquerystring(name, str) { var reg = new regexp("(^|&)" + name + "=([^&]*)(&|$)"); var r = str.substr(0).match(reg); if (r != null) return unescape(r[2]); return null; } $(function () { var css = ""); $('body').append(css); });