用html+css洗一个小米商城头部

可以的，以下是一个简单的示例代码：

HTML:

<header class="header">
  <div class="logo">
    <a href="#"><img src="https://cdn.cnbj1.fds.api.mi-img.com/mi-mall/84b567c7ba5b5d5c7a2f847746af9ef9.png" alt="小米商城"></a>
  </div>
  <nav class="nav">
    <ul>
      <li><a href="#">首页</a></li>
      <li><a href="#">小米手机</a></li>
      <li><a href="#">电视</a></li>
      <li><a href="#">笔记本</a></li>
      <li><a href="#">家电</a></li>
      <li><a href="#">智能</a></li>
      <li><a href="#">路由器</a></li>
    </ul>
  </nav>
  <div class="search">
    <form>
      <input type="text" placeholder="搜索商品">
      <button type="submit"><i class="icon-search"></i></button>
    </form>
  </div>
</header>

CSS:

.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px;
  background-color: #fff;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

.logo img {
  max-width: 120px;
}

.nav ul {
  display: flex;
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav li {
  margin-left: 30px;
}

.nav a {
  display: block;
  color: #333;
  font-size: 18px;
  text-decoration: none;
}

.search {
  position: relative;
}

.search input {
  width: 300px;
  height: 35px;
  padding: 5px 10px;
  border: none;
  border-radius: 5px;
  font-size: 16px;
}

.search button {
  position: absolute;
  top: 5px;
  right: 10px;
  width: 25px;
  height: 25px;
  border: none;
  background-color: transparent;
}

.search button i {
  display: block;
  width: 25px;
  height: 25px;
  background-image: url('https://cdn.cnbj1.fds.api.mi-img.com/mi-mall/1014a2bad283491516d4b99a4a695034.png');
  background-repeat: no-repeat;
  background-size: contain;
  background-position: center;
}

可以根据自己的需要进行调整，比如颜色、字体、布局等。