}, off: function (a, b) {
            for (var c, d, e = a.split(/\s+/); e.length;)for (a = e.shift(), c = this.length; c;)c -= 1, d = this[c], d.removeEventListener ? d.removeEventListener(a, b, !1) : d.detachEvent && d.detachEvent("on" + a, b);
            return this
        }, empty: function () {