function getPageScroll(){

	var yScroll;

	if (self.pageYOffset) {
		yScroll = self.pageYOffset;
	} else if (document.documentElement && document.documentElement.scrollTop){	 // Explorer 6 Strict
		yScroll = document.documentElement.scrollTop;
	} else if (document.body) {// all other Explorers
		yScroll = document.body.scrollTop;
	}

	arrayPageScroll = new Array('',yScroll) 
	return arrayPageScroll;
}

function getPageSize(){
	
	var xScroll, yScroll;
	
	if (window.innerHeight && window.scrollMaxY) {	
		xScroll = document.body.scrollWidth;
		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
		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 = windowWidth;
	} else {
		pageWidth = xScroll;
	}

	arrayPageSize = new Array(pageWidth,pageHeight,windowWidth,windowHeight) 
	return arrayPageSize;
}

function showdiv(valdiv, wfin)
{
	var arrayPageSize = getPageSize();
	var arrayPageScroll = getPageScroll();
		
	var objBody = document.getElementsByTagName("body").item(0);
	
	var objOverlay = document.createElement("div");
	objOverlay.setAttribute('id','overlay');
	objOverlay.style.height = (arrayPageSize[1] + 'px');
	//objOverlay.onclick = function () {hidediv(); return false;}
	objOverlay.style.display = 'block';
	objOverlay.style.position = 'absolute';
	objOverlay.style.top = '0';
	objOverlay.style.left = '0';
	objOverlay.style.zIndex = '90';
 	objOverlay.style.width = '101%';
	objBody.insertBefore(objOverlay, objBody.firstChild);
	
	var objLightbox = document.getElementById(valdiv);	
	//objLightbox.setAttribute('id','valdiv');
	objLightbox.style.display = 'block';
	objLightbox.style.position = 'absolute';
	objLightbox.style.zIndex = '100';	
	objLightbox.style.border = '1px solid #000000';	
	objLightbox.style.width = wfin;	
	//objLightbox.innerHTML = "Bonsoir je suis un div";	
	objLightbox.style.backgroundColor = '#FFFFFF';	
	objBody.insertBefore(objLightbox, objOverlay.nextSibling);	
	
		var lightboxTop = arrayPageScroll[1] + ((arrayPageSize[3]-350) / 2);
		var lightboxLeft = ((arrayPageSize[0]-500) / 2);
		
		objLightbox.style.top = "120px";
		objLightbox.style.left = (lightboxLeft < 0) ? "0px" : lightboxLeft + "px";
		
}

function hidediv(valdiv2)
{
var objLightbox = document.getElementById(valdiv2);	
var objOverlay = document.getElementById('overlay');	

objOverlay.style.display = 'none';
objLightbox.style.display = 'none';
}