可折叠侧边导航

本课属于 Coddy HTML 学习旅程的“JavaScript 实战”单元。第 14 课，共 27 课。

可折叠侧边导航是一个隐藏在屏幕侧面的菜单，点击按钮后会滑入屏幕。它既能节省空间，又能让用户快速访问导航链接。

创建一个包含侧边导航栏和切换按钮的基本 HTML 结构：

<button id="toggleNav">☰ Menu</button>

<nav id="sideNav" class="sidenav">
  <a href="#">Home</a>
  <a href="#">About</a>
  <a href="#">Services</a>
  <a href="#">Contact</a>
</nav>

添加 CSS 来设置侧边导航的样式：

.sidenav {
  height: 100%;
  width: 0;
  position: fixed;
  top: 0;
  left: 0;
  background-color: #111;
  overflow-x: hidden;
  transition: 0.3s;
  padding-top: 60px;
}

.sidenav.open {
  width: 250px;
}

添加 JavaScript 来切换导航栏的显示状态：

const toggleBtn = document.getElementById('toggleNav');
const sideNav = document.getElementById('sideNav');

toggleBtn.addEventListener('click', function() {
  sideNav.classList.toggle('open');
});

点击按钮时，侧边导航会根据当前状态滑入或滑出。

挑战

简单

让菜单按钮正常工作：

HTML：使用 onclick 属性将菜单按钮连接到一个 JavaScript 函数

JavaScript：编写一个函数，将侧边导航栏的宽度设置为 250px，从而打开它

亲手试试

<!DOCTYPE html>
<html>
<head>
  <title>Scandinavian Interior Design</title>
  <link rel="stylesheet" href="style.css">
</head>
<body>
  <div id="sideNav" class="sidenav">
    <a href="javascript:void(0)" class="close-btn" onclick="closeNav()">X</a>
    <a href="#">Home</a>
    <a href="#">Philosophy</a>
    <a href="#">Materials</a>
    <a href="#">Inspiration</a>
    <a href="#">Contact</a>
  </div>

  <header>
    <span class="open-btn">☰ Menu</span>
    <h1>Scandinavian Interior Design</h1>
  </header>

  <main>
    <section>
      <h2>Calm, Functional, Beautiful</h2>
      <p>
        Scandinavian design is about more than looks — it’s about balance,
        comfort, and harmony. Spaces are uncluttered, airy, and filled with
        light, making homes feel both inviting and practical.
      </p>
    </section>

    <section>
      <h2>Natural Materials</h2>
      <p>
        Wood, stone, wool, and linen are at the heart of Scandinavian interiors.
        These natural elements bring warmth and a sense of connection to nature,
        while ensuring that every item is purposeful and timeless.
      </p>
    </section>
  </main>

  <script src="script.js"></script>
</body>
</html>