<n* class="n*bar">
  <div class="n*-brand">Logo</div>
  <ul class="n*-menu">
    <li><a href="#">首页</a></li>
    <li><a href="#">关于</a></li>
    <li><a href="#">服务</a></li>
    <li><a href="#">联系</a></li>
  </ul>
  <div class="hamburger">
    <span></span>
    <span></span>
    <span></span>
  </div>
</n*>

.n*bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem;
  background-color: #333;
  color: white;
}

.n*-menu {
  display: flex;
  list-style: none;
  margin: 0;
  padding: 0;
}

.n*-menu li a {
  color: white;
  text-decoration: none;
  padding: 0.5rem 1rem;
}

.hamburger {
  display: none;
  flex-direction: column;
  cursor: pointer;
}

.hamburger span {
  width: 25px;
  height: 3px;
  background: white;
  margin: 3px 0;
  transition: 0.3s;
}

@media (max-width: 768px) {
  .hamburger {
    display: flex;
  }

  .n*-menu {
    display: none;
    flex-direction: column;
    width: 100%;
    background: #333;
  }

  .n*-menu.active {
    display: flex;
  }
}

<script>
  const hamburger = document.querySelector(".hamburger");
  const n*Menu = document.querySelector(".n*-menu");

  hamburger.addEventListener("click", () => {
    n*Menu.classList.toggle("active");
  });
</script>