* {
	margin:0;
	padding:0;
	list-style:none;
}
.nav {
	width:200px;
	margin:100px auto;
}
.nav>li {
	border:1px solid #000;
	line-height:35px;
	border-bottom:none;
	text-indent:15px;
	/*文字间隔*/
}
.nav>li:last-child {
	border-bottom:1px solid #000;
	border-bottom-right-radius:5px;
	border-bottom-left-radius:5px;
}
.nav>li:first-child {
	border-top-right-radius:5px;
	border-top-left-radius:5px;
}
.sub {
	display:none;
}
.sub>li {
	background:pink;
	border:1px solid white;
}
.sub>li:hover {
	background:#f40;
}