function mainmenu(){
$("#nav ul ").css({display: "none"}); // Opera Fix
$("#nav li").hover(function(){
		$(this).find('ul:first').css({visibility: "visible", display: "none"}).show(200);
		$(this).find('a.first').css({background: "url(images/menu_blue.jpg)"});
		},function(){
		$(this).find('ul:first').css({visibility: "hidden",display: "none"});
		$(this).find('a.first').css({background: "url(images/menu_green.jpg)"});
		});
}

$(document).ready(function(){					
	mainmenu();
});