if (document.images) {

home_on = new Image();
home_on.src = "images/nav_home_here.gif";
contact_on = new Image();
contact_on.src = "images/nav_contact_here.gif";
helpful_links_on = new Image();
helpful_links_on.src = "images/nav_helpful_links_here.gif";
sitemap_on = new Image();
sitemap_on.src = "images/nav_sitemap_here.gif";

home_off = new Image();
home_off.src = "images/nav_home.gif";
contact_off = new Image();
contact_off.src = "images/nav_contact.gif";
helpful_links_off = new Image();
helpful_links_off.src = "images/nav_helpful_links.gif";
sitemap_off = new Image();
sitemap_off.src = "images/nav_sitemap.gif";
}

function imgOn(imgName){
	if (document.images){
	document[imgName].src = eval(imgName + "on.src");
	}
}
	
function imgOff(imgName){
	if (document.images){
	document[imgName].src = eval(imgName + "off.src");
	}
}



// code for the main navigation's drop down menus
window.onerror = null;
window.defaultStatus = '';

var initialized = 0;
var menus = new Array();
var menustatus = new Array();
var menu_over = new Array();
var mytimer = 0;

var currentSection = 'none'


function init(){
	if(parseInt(navigator.appVersion) > 3){
	  for (var i=0; i<=5; i++)
		{
	    menustatus[i] = "closed";

		  if(document.layers){
        // Netscape 4
			  menus[i] = document["menu"+i]
			  menu_over[i] = document["menu"+i+"_over"];
			  menu_over[i].onmouseout = netscapehider;
		  }
		  else if (document.all) {
		    // IE
			  menus[i] = document.all["menu"+i].style;
			  menu_over[i] = document.all["menu"+i+"_over"].style;
			  document.all["menu"+i+"_over"].onmouseout = iehider;
		  }
		  else if (document.getElementById) {
		    // Standard
			  menus[i] = document.getElementById("menu"+i).style;
			  menu_over[i] = document.getElementById("menu"+i+"_over").style;
			  document.getElementById("menu"+i+"_over").onmouseout = hidemenu;
		  }
	  }
	}
	initialized = 1;
}

function show(menunumber){
  if(parseInt(navigator.appVersion) >= 4)
	{
	  if(menu_over[menunumber])
		{
		  menu_over[menunumber].visibility = 'visible';
			menu_over[menunumber].zIndex = '310';
		}
		menus[menunumber].visibility = 'visible';
		menus[menunumber].zIndex = '300';
		menustatus[menunumber] = 'open';
  }
}

function closeWindows(){
	if (parseInt(navigator.appVersion) >= 4)
		clearTimeout(mytimer);
	clearmenus();

	if(parseInt(navigator.appVersion) >= 4){
		for(i=0; i<menus.length; i++){
			if(menustatus[i] == 'open'){
				if(menu_over[i]){
					menu_over[i].visibility = 'hidden';
					menu_over[i].zIndex = '110';
				}
				menus[i].visibility = 'hidden';
				menus[i].zIndex = '100';
				menustatus[i] = 'closed';
			}
		}
	}
}

function menuOutHandler(){
	if(initialized)
	{
		if (parseInt(navigator.appVersion) < 4)
			closeWindows();
		else
			mytimer = setTimeout(closeWindows, 5);
	}
}

function imagerep(imgname, divname){
	if(parseInt(navigator.appVersion) >= 4){
		clearTimeout(mytimer);

		if(document.layers)
		  eval("window.document." + divname + ".document['" + imgname + "'].src = " + imgname + "_over.src");
		else
		  eval("document['" + imgname + "'].src = " + imgname + "_over.src");
	}
	else{
		if(navigator.appName == "Netscape"){
			eval("document['imgmenu" + imgname + "'].src = menu" + imgname + "_over.src");
			menustatus[imgname] = "open";
		}
	}
}

function eraseimage(imgname, divname, spacer){
	if(parseInt(navigator.appVersion) >= 4){
		if(document.layers)
		  eval("window.document." + divname + ".document['" + imgname + "'].src = " + spacer + ".src");
		else
		  eval("document['" + imgname + "'].src = " + spacer + ".src");
	}
	else{
		if(navigator.appName == "Netscape"){
		eval("document['imgmenu" + imgname + "'].src = menu" + imgname + "off.src");
		}
	}
}

function netscapehider()
{
	if(initialized) closeWindows();
}

function iehider()
{
	if(window.event.toElement && window.event.toElement.className != "menu") closeWindows();
}

function hidemenu(evnt) {
	if (initialized) {
		if (document.all) { if (window.event.toElement.className != 'menu') closeWindows();}
		else if (evnt.relatedTarget) { if (evnt.relatedTarget.className != 'menu') closeWindows();}
	}
}

function change(Name,Image,No,Msg) {
	if (document.images) {
		document [Name].src = eval(Image + No + ".src");
	}
	if (Msg) self.status = eval(Image + "2");
	return true;
}

// Caches the dropdown menus
if (!document.images) {}

else {
//----- browns_program menu ------
	var nav_accomplishments_over = new Image();
	nav_accomplishments_over.src ="images/nav_browns_accomp_over.gif";
	var nav_mission_over = new Image();
	nav_mission_over.src ="images/nav_browns_mission_over.gif";
	var nav_staff_over = new Image();
	nav_staff_over.src ="images/nav_browns_staff_over.gif";
	
//----- projects menu ----
	var nav_project1_over = new Image();
	nav_project1_over.src ="images/nav_project1_over.gif";
	var nav_project2_over = new Image();
	nav_project2_over.src ="images/nav_project2_over.gif";
	var nav_project3_over = new Image();
	nav_project3_over.src ="images/nav_project3_over.gif";
	var nav_project4_over = new Image();
	nav_project4_over.src ="images/nav_project4_over.gif";
	var nav_project5_over = new Image();
	nav_project5_over.src ="images/nav_project5_over.gif";
	var nav_project6_over = new Image();
	nav_project6_over.src ="images/nav_project6_over.gif";
	var nav_project7_over = new Image();
	nav_project7_over.src ="images/nav_project7_over.gif";
	var nav_project8_over = new Image();
	nav_project8_over.src ="images/nav_project8_over.gif";

//----- cores menu ------
	var nav_coreA_over = new Image();
	nav_coreA_over.src ="images/nav_coreA_over.gif";
	var nav_coreB_over = new Image();
	nav_coreB_over.src ="images/nav_coreB_over.gif";
	var nav_coreC_over = new Image();
	nav_coreC_over.src ="images/nav_coreC_over.gif";
	var nav_coreD_over = new Image();
	nav_coreD_over.src ="images/nav_coreD_over.gif";
	var nav_coreE_over = new Image();
	nav_coreE_over.src ="images/nav_coreE_over.gif";
	var nav_coreF_over = new Image();
	nav_coreF_over.src ="images/nav_coreF_over.gif";
	var nav_coreG_over = new Image();
	nav_coreG_over.src ="images/nav_spacer.gif";
	
//----- sites menu ------
	var nav_sites_superfund_over = new Image();
	nav_sites_superfund_over.src ="images/nav_sites_superfund_over.gif";
	var nav_sites_brownfields_over = new Image();
	nav_sites_brownfields_over.src ="images/nav_sites_brownfields_over.gif";
	
//----- news menu ------
	var nav_news_news_over = new Image();
	nav_news_news_over.src ="images/nav_news_news_over.gif";
	var nav_news_events_over = new Image();
	nav_news_events_over.src ="images/nav_news_events_over.gif";

	var spacer1=new Image();
	spacer1.src="images/nav_spacer1.gif";
	var spacer2=new Image();
	spacer2.src="images/nav_spacer2.gif";
	
	nav_browns0=new Image();
	nav_browns0.src="images/nav_index_browns0.gif";
	nav_browns1=new Image();
	nav_browns1.src="images/nav_index_browns1.gif";

	nav_projects0=new Image();
	nav_projects0.src="images/nav_index_projects0.gif";
	nav_projects1=new Image();
	nav_projects1.src="images/nav_index_projects1.gif";

	nav_cores0=new Image();
	nav_cores0.src="images/nav_index_cores0.gif";
	nav_cores1=new Image();
	nav_cores1.src="images/nav_index_cores1.gif";
	
	nav_sites0=new Image();
	nav_sites0.src="images/nav_index_sites0.gif";
	nav_sites1=new Image();
	nav_sites1.src="images/nav_index_sites1.gif";
	
	nav_news0=new Image();
	nav_news0.src="images/nav_index_news0.gif";
	nav_news1=new Image();
	nav_news1.src="images/nav_index_news1.gif";
	
	nav_publications0=new Image();
	nav_publications0.src="images/nav_index_publications0.gif";
	nav_publications1=new Image();
	nav_publications1.src="images/nav_index_publications1.gif";
}

function clearmenus(){
	if (currentSection != 'browns_program')
		change('imgmenu0','nav_browns',0);
	if (currentSection != 'projects')
		change('imgmenu1','nav_projects',0);
	if (currentSection != 'cores')
		change('imgmenu2','nav_cores',0);
	if (currentSection != 'sites')
		change('imgmenu3','nav_sites',0);
	if (currentSection != 'news')
		change('imgmenu4','nav_news',0);
	if (currentSection != 'publications')
		change('imgmenu5','nav_publications',0);
}