Add $(".wall").css("background",'#fff');
to #highlight_lose
and #finish
$('#highlight_lose').bind('mouseleave', function() {
$(this).fadeOut(400);
$(".wall").css("background",'#fff');
})
$('#finish').bind('mouseenter', function() {
$('#highlight_win').fadeIn(400);
$(".wall").css("background",'#fff');
})