function SetOverlaySize()
{
	el1 = document.getElementById("container");
	el2 = document.getElementById("fade-overlay");
	el2.style.width = el1.clientWidth + "px";
	el2.style.height = el1.clientHeight + "px";
}

function MainNav()
{
	var k = 1;
	var z = 0;
	fadeOpacity.addRule('R1', 0.0, 0.4, 35);
	fadeOpacity.addRule('R2', 0.0, 1.0, 20);

	var overlayFade = document.getElementById("fade-overlay");
	var contentFade = document.getElementById("container-content");
	
	navRoot = document.getElementById("navigation").getElementsByTagName("ul")[0];
	for (i=0; i<navRoot.childNodes.length; i++)
	{
		node = navRoot.childNodes[i];

		if (node.nodeName=="LI")
		{	
			node.id="item-"+ k;		k++;
			z = i;
			
			node.onmouseover=function()
			{
				this.className+=" sfhover";
				str = this.id;	str = str.substring(str.length-1,str.length);

				var nodeblock = document.getElementById("block-"+str);
				if (document.body.filters && navigator.appVersion.match(/MSIE ([\d.]+);/)[1]<6)
				{
					nodeblock.style.filter = "alpha(opacity=100)";
					overlayFade.style.filter = "alpha(opacity=40)";

				} else {
							fadeOpacity(nodeblock.id, 'R2');
							fadeOpacity(overlayFade.id, 'R1');
						}
				contentFade.style.zIndex=100;
				
				newnode = this;
				bool = false;
				for (j=0; j<4; j++)
			    if (newnode.nextSibling) if (bool==false)
				{
					newnode = newnode.nextSibling;					
					if (newnode.nodeName=="LI")
					{
						newnode.className+=" sfhover-second";
						bool = true;
					}
				}

			}
			node.onmouseout=function()
			{
				this.className=this.className.replace("sfhover", "");
				str = this.id;	str = str.substring(str.length-1,str.length);

				var nodeblock = document.getElementById("block-"+str);
				if (document.body.filters && navigator.appVersion.match(/MSIE ([\d.]+);/)[1]<6)
				{
					nodeblock.style.filter = "alpha(opacity=0)";
					overlayFade.style.filter = "alpha(opacity=0)";

				} else {
							fadeOpacity.back(nodeblock.id);
							fadeOpacity.back(overlayFade.id);
						}
				contentFade.style.zIndex=498;
				
				bool = false;
				newnode = this;
				for (j=0; j<2; j++)
			    if (newnode.nextSibling) if (bool==false)
				{	
					newnode = newnode.nextSibling;					
					if (newnode.nodeName=="LI")
					{						
						newnode.className=newnode.className.replace("sfhover-second", "");
						bool = true;
					}
				}
			}

		}
	}
	nd = navRoot.childNodes[z];
	nd.className+=" last-child-li";
	
	SetOverlaySize();
}