.top {
	width: 100%;
	height: 60px;
	box-shadow: 0 0 10px 5px rgba(0, 0, 0, 0.2);
	font-family: 等线;
	font-size: 18px;
	line-height: 20px;
}

.nav {
	position: absolute;
	width: 600px;
	height: 60px;
	right: 100px;
}

.nav div {
	list-style: none;
	float: left;
}

.nav div a {
	text-align: center;
	position: relative;
	display: block;
	padding: 5px 20px;
	margin: 20px 0;
}

.nav div a:hover {
	color: #fff;
}

.nav div a:before {
	content: ' ';
	position: absolute;
	top: 0;
	left: 0;
	width: 100%;
	height: 30px;
	border-top: 1px solid #555;
	border-bottom: 1px solid #555;
	transform: scaleY(2);
	opacity: 0;
	transition: 0.8s;
}

.nav div a:hover:before {
	transform: scaleY(1);
	opacity: 1;
}

.nav div a:after {
	content: ' ';
	position: absolute;
	top: 1px;
	left: 0;
	width: 100%;
	height: 30px;
	background: #555;
	transform: scale(0);
	transition: 0.8s;
	z-index: -1;
}

.nav div a:hover:after {
	transform: scale(1);
}

.box2 {
	height: 180px;
	display: none;
	position: relative;
	width: 100%;
	z-index: 999;
}