nav {
margin:100px auto;
text-align:center;
}
nav ul {
border-radius:10px;
background:linear-gradient(to bottom,#efefef,#bbbbbb);
padding:0 20px;
display:inline-table;
position:relative;
box-shadow:1px 1px 3px #666;
}
nav ul ul {
display:none;
}
nav ul li {
float:left;
}
nav ul::after {
content:"";
display:block;
clear:both;
}
nav ul li a {
display:block;
padding:25px 40px;
color:#000;
text-decoration:none;
font-family:"微软雅黑";
}
nav ul li:hover > ul {
display:block;
}
nav ul li:hover {
background:linear-gradient(to bottom,#4f5964,#5f6975);
}
nav ul li:hover a {
color:#FFF;
}
nav ul ul {
background:#5f6975;
border-radius:0;
position:absolute;
top:100%;
padding:0;
}
nav ul ul li {
float:none;
border-top:1px solid #6b727c;
border-bottom:1px solid #575f6a;
}
nav ul ul li a {
color:#FFF;
}
nav ul ul li a:hover {
background:#4b545f;
}
nav ul ul ul {
width:100%;
position:absolute;
left:100%;
top:50%;
}