Mobile.js
/* Any JavaScript here will be loaded for users using the mobile site */
window.dataLayer = window.dataLayer || [];
function gtag(){dataLayer.push(arguments);}
gtag('js', new Date());
gtag('config', 'G-S339JBKYQJ');
$('head').append($('<script/>').attr('async', 1).attr('src', 'https://www.googletagmanager.com/gtag/js?id=G-S339JBKYQJ'));