$(function() {
	var ms = 200;
	$("#nav > li").each(function() {
		var item = $(this);
		var wrapper = item.find("div");
		var subMenu = wrapper.children();
		wrapper.css({visibility: "hidden", display: "block"});
		var subMenuHeight = wrapper.height();
		subMenu.css({marginTop: -subMenuHeight});
		wrapper.css({visibility: "inherit", overflow: "hidden"});
		item.hover(
			function() {
				subMenu.stop(true);
				var curPos = parseFloat(subMenu.css("margin-top"));
				subMenu.animate({marginTop: 0}, ms * -curPos / subMenuHeight);
			},
			function() {
				subMenu.animate({marginTop: -subMenuHeight}, ms);
			}
		);
	});
});