/**
 * COMMON DHTML FUNCTIONS
 * These are handy functions I use all the time.
 * By Seth Banks (webmaster at subimage dot com)
 * http://www.subimage.com/
 * Up to date code can be found at http://www.subimage.com/dhtml/
 * This code is free for you to use anywhere, just keep this comment block.
 */
function addEvent(obj, evType, fn){
	if (obj.addEventListener){
		obj.addEventListener(evType, fn, false);
		return true;
	} else if (obj.attachEvent){
		var r = obj.attachEvent("on"+evType, fn);
		return r;
	} else {
		return false;
	}
}
function removeEvent(obj, evType, fn, useCapture){
	if (obj.removeEventListener){
		obj.removeEventListener(evType, fn, useCapture);
		return true;
	} else if (obj.detachEvent){
		var r = obj.detachEvent("on"+evType, fn);
		return r;
	} 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() {
	var offset = 17;
	var width = null;
	if (window.innerWidth!=window.undefined) return window.innerWidth; 
	if (document.compatMode=='CSS1Compat') return document.documentElement.clientWidth; 
	if (document.body) return document.body.clientWidth; 
}
function getScrollTop() {
	if (self.pageYOffset){
		return self.pageYOffset;
	}else if (document.documentElement && document.documentElement.scrollTop){
		return document.documentElement.scrollTop;
	}else if (document.body){
		return document.body.scrollTop;
	}
}
function getScrollLeft() {
	if (self.pageXOffset){
		return self.pageXOffset;
	}else if (document.documentElement && document.documentElement.scrollLeft){
		return document.documentElement.scrollLeft;
	}else if (document.body){
		return document.body.scrollLeft;
	}
}