老师，帮我检查下代码，看哪里需要修改或优化

首页课程实战体系课手记专栏慕课教程

来源：3-17 编程练习

慕姐5289795

2021-07-19 19:14:16

问题描述：

帮我检查下代码
感觉卡片上的加入购物车按钮中文字没有垂直居中，不知道是不是错觉，使用line-height和flex的align-items: center都没有任何变化，求解

相关代码：

<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title></title>
    <style>
     /* 在此处补充代码*/
     * {
         padding: 0;
         margin: 0;
     }
     body {
         width: 1000px;
         /*height: 100vh;*/
     }
     header {
         height:60px;
         background-color: rgb(0, 0, 0);
         display: flex;
         justify-content: space-around;
         align-items: center;
     }

     header .logo img {
         height: 60px;
         display: block;
     }

     header .nav {
         list-style: none;
         height: 100%;
         color: white;
         display: flex;
         width: 300px;
     }

     header .nav li {
         flex: 1;
         display: flex;
         justify-content: center;
         align-items: center;
     }

     header .login {
         flex-basis: 80px;
         display: flex;
         justify-content: space-between;
     }

     header .login input {
         width: 30px;
         height: 20px;
         line-height: 20px;
         background-color: orange;
         color: white;
         border: none;
         border-radius: 2px;
     }

     .main {
         height: 240px;
         display: flex;
         flex-wrap: wrap;
         justify-content: space-around;
         align-items: center;
     }

     .main .section {
         background-color: lightblue;
         width: 45%;
         height: 40%;
         padding: 5px;
         border-radius: 5px;
         display: flex;
         justify-content: space-around;
         align-items: center;
     }

     .main .section .box {
         height: 100%;
         display: flex;
         flex-direction: column;
         justify-content: space-around;
     }

     .main .section .shopping {
         padding: 5px;
         background-color: orange;
         color: white;
         border-radius: 5px;
     }
    </style>
</head>
<body>
<!-- 头部 -->
   <header>
     <div class="logo">
       <img src="http://climg.mukewang.com/59197ab000014f1503000100.jpg" alt="">
     </div>
       <ul class="nav">
         <li>课程</li>
         <li>路径</li>
         <li>猿问</li>
         <li>手记</li>
       </ul>     
     <div class="login">
       <input type="button" value="登录">
       <input type="button" value="注册">
     </div>
   </header>
<!-- 主体内容 -->
   <section class="main">
    <div class="section">
      <div class="box">
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      </div>
      <div class="shopping">
        <div class="btn">加入购物车</div>
      </div>
    </div>
    <div class="section">
      <div class="box">
        <p>《HTML5月CSS3实现动态网页》</p>
        <div>适用人群：有html和css基础的童鞋</div>
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      </div>
      <div class="shopping">
        <div class="btn">加入购物车</div>
      </div>
    </div>
    <div class="section">
      <div class="box">
        <p>《从H5网页开发到移动端响应式开发》</p>
        <div>适用人群：有html、css、js、jq基础的童鞋</div>
        <div>费用：￥599</div>
      </div>
      <div class="shopping">
        <div class="btn">加入购物车</div>
      </div>
    </div>
    <div class="section">
      <div class="box">
        <p>《前端工程师进阶全栈》</p>
        <div>适用人群：有前段开发经验的童鞋</div>
        <div>费用：￥1599</div>
      </div>
      <div class="shopping">
        <div class="btn">加入购物车</div>
      </div>
    </div>
    </section>  
</body>
</html>