$(function(){
	$("#nav li a")
		.hover(function(){
			$(this).animate({
				backgroundPosition: "0 -140px"
			}, 100)
		}, function() {
			$(this).animate({
				backgroundPosition: "0 -183px"
			}, 100)
		})
		.mousedown(function(){
			$(this).css({
				backgroundPosition: "0 -220px"
			})	
		});
});

$(function() {
	$(window).scroll(function(){
		var scrollTop = $(window).scrollTop();
		if(scrollTop != 0)
			$('#nav').stop().animate({'opacity':'0.4'},400);
		else
			$('#nav').stop().animate({'opacity':'1'},400);
	});

	$('#nav').hover(
		function (e) {
			var scrollTop = $(window).scrollTop();
			if(scrollTop != 0){
				$('#nav').stop().animate({'opacity':'1'},400);
			}
		},
		function (e) {
			var scrollTop = $(window).scrollTop();
			if(scrollTop != 0){
				$('#nav').stop().animate({'opacity':'0.4'},400);
			}
		}
	);
});