function getPageSize(){
	 var xScroll, yScroll;
	
	if (window.innerHeight && window.scrollMaxY) {	
		xScroll = window.innerWidth + window.scrollMaxX;
		yScroll = window.innerHeight + window.scrollMaxY;
	} else if (document.body.scrollHeight > document.body.offsetHeight){ // all but Explorer Mac
		xScroll = document.body.scrollWidth;
		yScroll = document.body.scrollHeight;
	} else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
		xScroll = document.body.offsetWidth;
		yScroll = document.body.offsetHeight;
	}
	
	var windowWidth, windowHeight;
	
	if (self.innerHeight) {	// all except Explorer
		if(document.documentElement.clientWidth){
			windowWidth = document.documentElement.clientWidth; 
		} else {
			windowWidth = self.innerWidth;
		}
		windowHeight = self.innerHeight;
	} else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
		windowWidth = document.documentElement.clientWidth;
		windowHeight = document.documentElement.clientHeight;
	} else if (document.body) { // other Explorers
		windowWidth = document.body.clientWidth;
		windowHeight = document.body.clientHeight;
	}	
	
	// for small pages with total height less then height of the viewport
	if(yScroll < windowHeight){
		pageHeight = windowHeight;
	} else { 
		pageHeight = yScroll;
	}

	// for small pages with total width less then width of the viewport
	if(xScroll < windowWidth){	
		pageWidth = xScroll;		
	} else {
		pageWidth = windowWidth;
	}

	return [pageWidth,pageHeight];
}

function showLightbox(base) {
	urchinTracker(base+'/lightbox/show');
	
	// position lightbox
	var objLightbox = document.getElementById('lightbox');
	var objOverlay = document.getElementById('overlay');

	var widthLightbox = 500;
	var heightLightbox = 300;

	var arrayPageSize = getPageSize();	
	
	objOverlay.style.display = "block";
	objLightbox.style.display = "block";

	objLightbox.style.left = ((arrayPageSize[0]-widthLightbox)/2)+'px';
	objLightbox.style.top = ((arrayPageSize[1]-heightLightbox)/2)+'px';
	
	objOverlay.style.height = arrayPageSize[1]+'px';
	
	t=setTimeout("hideLightbox('"+base+"')",7000);
}

function hideLightbox(base) {
	urchinTracker(base+'/lightbox/hide');
	document.getElementById('lightbox').style.display = "none";
	document.getElementById('overlay').style.display = "none";
}