usr = window.navigator.userAgent;
browserVers = parseInt(usr.charAt(usr.indexOf("/")+1),10);

function _img_new(arg)
{
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function _elem_find(n,x)
{
	if (browserVers < 4) return document[n];
	var d = x ? x.document : document;
	var e = d[n];
	if (!e) {
		for (var i=0;i<d.layers.length;i++) {
			e = _elem_find(n,d.layers[i]);
			if (e) return e;
		}
	}
	return e;
}

function _ic()
{
	if (document.images && (ispreloaded == true))
	{
		var p;
		for (var i=0; i<_ic.arguments.length; i+=2)
		{
			p = null;
			if (document.layers)
				p = _elem_find(_ic.arguments[i],0);
			else
				p = document.images[_ic.arguments[i]];

			if (p)
				p.src = _ic.arguments[i+1];
		}
	}
}

var ispreloaded = false;

function _img_preload()
{
	if (document.images)
	{
		top_menu1_over = _img_new("z/top_menu1-over.gif");
		top_menu_2_over = _img_new("z/top_menu_2-over.gif");
		top_menu_3_over = _img_new("z/top_menu_3-over.gif");
		top_menu_4_over = _img_new("z/top_menu_4-over.gif");
		top_menu_5_over = _img_new("z/top_menu_5-over.gif");
		bar_questions_over = _img_new("z/bar_questions-over.gif");
		bar_cardorder_over = _img_new("z/bar_cardorder-over.gif");
		bar_cardregister_over = _img_new("z/bar_cardregister-over.gif");
		ispreloaded = true;
	}
}

function _change_visibility(e)
{
	if (e.style.visibility=='visible')
	{
		e.style.visibility='hidden';
		e.style.height='auto';
	}
	else
	{
		e.style.visibility='visible'
		e.style.height='0';
	}
}

function _change_display_block_none(e)
{
	if (e.style.display=='block')
	{
		e.style.display='none';
	}
	else
	{
		e.style.display='block'
	}
}