Touchscreen detection on first touch.js

(function() {
    // Test if is touch device
    if(typeof window.addEventListener == 'function')
    {
        window.addEventListener('touchstart', function setHasTouch() {
            document.getElementsByTagName('html')[0].className += ' is-touch-screen'
            window.removeEventListener('touchstart', setHasTouch);
        }, false);
    }
})();