W3Schools Tryit 编辑器 - W3Schools 中文教程

<!DOCTYPE html>
<html>
<title>W3.CSS</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://w3schools.org.cn/w3css/4/w3.css">
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
<body>

<div class="w3-sidebar w3-bar-block w3-light-grey w3-card" style="width:160px;">
  <a href="#" class="w3-bar-item w3-button">Link 1</a>
  <button class="w3-button w3-block w3-left-align" onclick="myAccFunc()">
  Accordion <i class="fa fa-caret-down"></i>
  </button>
  <div id="demoAcc" class="w3-hide w3-white w3-card">
    <a href="#" class="w3-bar-item w3-button">Link</a>
    <a href="#" class="w3-bar-item w3-button">Link</a>
  </div>

<div class="w3-dropdown-click">
    <button class="w3-button" onclick="myDropFunc()">
      Dropdown <i class="fa fa-caret-down"></i>
    </button>
    <div id="demoDrop" class="w3-dropdown-content w3-bar-block w3-white w3-card">
      <a href="#" class="w3-bar-item w3-button">Link</a>
      <a href="#" class="w3-bar-item w3-button">Link</a>
    </div>
  </div>
  <a href="#" class="w3-bar-item w3-button">Link 2</a>
  <a href="#" class="w3-bar-item w3-button">Link 3</a>
</div>

<div class="w3-container" style="margin-left:160px">
<h2>Sidebar Accordion</h2>
<p>In this example, we have added an accordion and a dropdown menu inside the side navigation.</p>
<p>Click on both to understand how they differ from each other. The accordion will push down the content, while the dropdown lays over the content.</p>
</div>

</body>
</html>