做一个简单的横向的导航
<!DOCTYPE html>
<html>
<head>
<meta charset ="utf-8">
<style type="text/css">
ul li{list-style:none;width:100px;height:20px;background-color:red;float:left;}
</style>
</head>
<body>
<ul>
<li>导航1</li>
<li>导航2</li>
<li>导航3</li>
</ul>
</body>
</html>