js横向二级导航菜单

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>横向二级导航菜单</title>
    <style>
        ul {
            list-style-type: none;
            margin: 0;
            padding: 0;
            overflow: hidden;
            background-color: #333;
        }
        li {
            float: left;
        }
        li a, .dropbtn {
            display: inline-block;
            color: white;
            text-align: center;
            padding: 14px 16px;
            text-decoration: none;
        }
        li a:hover, .dropdown:hover .dropbtn {
            background-color: #111;
        }
        .dropdown-content {
            display: none;
            position: absolute;
            background-color: #f9f9f9;
            min-width: 160px;
            box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
            z-index: 1;
        }
        .dropdown-content a {
            color: black;
            padding: 12px 16px;
            text-decoration: none;
            display: block;
            text-align: left;
        }
        .dropdown-content a:hover {
            background-color: #f1f1f1;
        }
        .dropdown:hover .dropdown-content {
            display: block;
        }
    </style>
</head>
<body>

<ul>
  <li><a href="#home">Home</a></li>
  <li class="dropdown">
    <a href="javascript:void(0)" class="dropbtn">Services</a>
    <div class="dropdown-content">
      <a href="#">Service 1</a>
      <a href="#">Service 2</a>
      <a href="#">Service 3</a>
    </div>
  </li>
  <li><a href="#contact">Contact</a></li>
</ul>

</body>
</html>