nav {
	width: 1200px;
	height: 40px;
	/*position: sticky;
	top: 0px;
	z-index: 99999;*/
	/*导航吸顶效果*/
	background: url(../images/nav-bj.jpg)repeat-x;
}
nav li {
	width: 199px;
	height: 40px;
	line-height: 36px;
	float: left;
	text-align: center;
	position: relative;
}
nav li a {
	color: #333;
	display: inline-block;
	width: 100%;
	height: 100%;
}
nav li:hover {
	background: url(../images/nav-bj2.jpg)repeat-x;
}

nav i {
	width: 1px;
    height: 16px;
    margin-top: 12px;
    background: #bbb;
    display: inline-block;
    float: left;
}
nav dl {
	position: absolute;
	top: 40px;
	z-index: 3;
	width: 100%;
	
}
nav li:hover dl dd{
	height: 40px;
	border-top: 1px solid #ccc;
}
nav dd {
	height: 0px;
	overflow: hidden;
	transition: ease 0.5s;
	background: #e5e5e5;
}
nav dd a {
	color: #333;
}
nav dd a:hover {
	background: url(../images/nav-bj2.jpg)repeat-x;
	color: #333;
}