function addEvent(d, c, a) {
	if (d.addEventListener) {
		d.addEventListener(c, a, false);
		return true;
	} else {
		if (d.attachEvent) {
			var b = d.attachEvent("on" + c, a);
			return b;
		} else {
			return false;
		}
	}
}
function removeEvent(e, d, b, a) {
	if (e.removeEventListener) {
		e.removeEventListener(d, b, a);
		return true;
	} else {
		if (e.detachEvent) {
			var c = e.detachEvent("on" + d, b);
			return c;
		} else {
			alert("Handler could not be removed");
		}
	}
}
function getViewportHeight() {
	if (window.innerHeight != window.undefined) {
		return window.innerHeight;
	}
	if (document.compatMode == "CSS1Compat") {
		return document.documentElement.clientHeight;
	}
	if (document.body) {
		return document.body.clientHeight;
	}
	return window.undefined;
}
function getViewportWidth() {
	if (window.innerWidth != window.undefined) {
		return window.innerWidth;
	}
	if (document.compatMode == "CSS1Compat") {
		return document.documentElement.clientWidth;
	}
	if (document.body) {
		return document.body.clientWidth;
	}
	return window.undefined;
}