請使用支持HTML5的浏覽器查看效果：
以下是源代碼：
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>HTML5最基本的橫行菜單代碼-</title>
<style>
body, ul, li, a {
margin: 0;
padding: 0;
}
#nav_keleyi_com {
width: 300px;
height: 35px;
background-color: #CCC;
margin: 0 auto;
}
#nav_keleyi_com ul {
list-style: none;
}
#nav_keleyi_com ul li {
display: block;
float: left;
height: 35px;
line-height: 35px;
text-align: center;
}
#nav_keleyi_com ul li a {
display: block;
float: left;
height: 35px;
text-decoration: none;
padding: 0 10px;
}
#nav_keleyi_com ul li a:hover {
color: #fff;
background-color: #000;
}
</style>
</head>
<body>
<nav id="nav_keleyi_com">
<ul>
<li><a href="http:///">Home</a></li>
<li><a href="http:///ablut/">About</a></li>
<li><a href="http:///a/bjac/kjsrt3b0.htm">Services</a></li>
<li><a href="http:///a/bjac/182di68b.htm">Contact</a></li>
</ul>
</nav>
</body>
</html>