var btn_home = new Image();
var btn_home_o = new Image();
var btn_catalog = new Image();
var btn_catalog_o = new Image();
var btn_about_us = new Image();
var btn_about_us_o = new Image();
var btn_services = new Image();
var btn_services_o = new Image();
var btn_tips = new Image();
var btn_tips_o = new Image();
var btn_contact_us = new Image();
var btn_contact_us_o = new Image();
function changeImages(par)
{
	if(document.images && preloadFlag == true)
	{
		if(par == "btn_home") document.btn_home.src = btn_home.src;
		if(par == "btn_home_o") document.btn_home.src = btn_home_o.src;
		if(par == "btn_catalog") document.btn_catalog.src = btn_catalog.src;
		if(par == "btn_catalog_o") document.btn_catalog.src = btn_catalog_o.src;
		if(par == "btn_about_us") document.btn_about_us.src = btn_about_us.src;
		if(par == "btn_about_us_o") document.btn_about_us.src = btn_about_us_o.src;
		if(par == "btn_services") document.btn_services.src = btn_services.src;
		if(par == "btn_services_o") document.btn_services.src = btn_services_o.src;
		if(par == "btn_tips") document.btn_tips.src = btn_tips.src;
		if(par == "btn_tips_o") document.btn_tips.src = btn_tips_o.src;
		if(par == "btn_contact_us") document.btn_contact_us.src = btn_contact_us.src;
		if(par == "btn_contact_us_o") document.btn_contact_us.src = btn_contact_us_o.src;
	}
}
var preloadFlag = false
function preloadImages()
{
	if (document.images)
	{
		btn_home.src = "images/btn_home.gif";
		btn_home_o.src = "images/btn_home_o.gif";
		btn_catalog.src = "images/btn_catalog.gif";
		btn_catalog_o.src = "images/btn_catalog_o.gif";
		btn_about_us.src = "images/btn_about_us.gif";
		btn_about_us_o.src = "images/btn_about_us_o.gif";
		btn_services.src = "images/btn_services.gif";
		btn_services_o.src = "images/btn_services_o.gif";
		btn_tips.src = "images/btn_tips.gif";
		btn_tips_o.src = "images/btn_tips_o.gif";
		btn_contact_us.src = "images/btn_contact_us.gif";
		btn_contact_us_o.src = "images/btn_contact_us_o.gif";
	}
	preloadFlag = true;
}