var DL1 = (document.implementation && document.implementation.hasFeature && document.implementation.hasFeature("html","1.0")) ? true : false;
var IE4 = ((navigator.appName.indexOf("Microsoft") != -1) && document.all) ? true : false;
var NS4 = ((navigator.appName.indexOf("Netscape") != -1) && document.layers) ? true : false;

var isMac = (navigator.userAgent.indexOf("Mac") != -1) ? true : false;
var isWin = (navigator.userAgent.indexOf("Win") != -1) ? true : false;

var isIE = (navigator.appName.indexOf("Microsoft") != -1) ? true : false;
var isNS = (navigator.appName.indexOf("Netscape") != -1) ? true : false;

var undefined;

function getWindowHeight() {	
	if (isNS) {
		return self.innerHeight;
	} else if (isIE) {
		return document.body.clientHeight;
	}
}
function getWindowWidth() {	
	if (isNS) {
		return self.innerWidth;
	} else if (isIE) {
		return document.body.clientWidth;
	}
}
function center(VALUE1,VALUE2) {
	return (VALUE1 - VALUE2) / 2;
}
function disableScroll(WINDOW){
	WINDOW.document.body.style.overflow = 'hidden';
}
function hideScroll(WINDOW){
	WINDOW.document.body.style.overflow = 'auto';
}
function showScroll(WINDOW){
	WINDOW.document.body.style.overflow = '';
}