js实现导航栏hover效果

<nav class="navbar">
  <ul>
    <li><a href="#home">Home</a></li>
    <li><a href="#services">Services</a></li>
    <li><a href="#about">About</a></li>
    <li><a href="#contact">Contact</a></li>
  </ul>
</nav>

.navbar ul {
  list-style-type: none;
  padding: 0;
}

.navbar li {
  display: inline-block;
  margin-right: 10px;
}

.navbar a {
  text-decoration: none;
  color: #333;
  padding: 5px 10px;
  transition: background-color 0.3s, color 0.3s;
}

.navbar a:hover {
  background-color: #007bff;
  color: white;
}

document.querySelectorAll('.navbar a').forEach(link => {
  link.addEventListener('mouseenter', function() {
    this.style.opacity = '0.7';
  });
  link.addEventListener('mouseleave', function() {
    this.style.opacity = '1';
  });
});