var agt = navigator.userAgent.toLowerCase();
var px = !!(agt.indexOf("msie 5.") > -1 && agt.indexOf('mac_powerpc') > -1) ? 'px' : '';
var winHeight = 0;
var winWidth = 0;

function winhoogte(){
	if( typeof( window.innerWidth ) == 'number' ) {//Non-IE
		winWidth = window.innerWidth;
		winHeight = window.innerHeight;
	} else if( document.documentElement &&( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {//IE6+ no-quirk
		winWidth = document.documentElement.clientWidth;
		winHeight = document.documentElement.clientHeight;
	} else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {//IE 4 compat
		winWidth = document.body.clientWidth;
		winHeight = document.body.clientHeight;
	}
}

function htmlbodyhoogte(){
	if(!document.body){ return }
	var x=0;
	var test1 = document.body.scrollHeight;
	var test2 = document.body.offsetHeight;
	if (test1 > test2) { // all but Explorer Mac
		x = document.body.scrollWidth;
		return document.body.scrollHeight;
	} else { // Explorer Mac; would also work in Explorer 6 Strict, Mozilla and Safari
		x = document.body.offsetWidth;
		return document.body.offsetHeight;
	}
}