老师请帮看下代码是否需要完善？

来源：2-4 编程练习

Nyakoonya

2020-08-21 17:01:44

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
    /*此处写代码*/
    body,div,span{
        margin: 0;
        padding:0;
    }
    .nav{
        width: 1100px;
        height: 100px;
        background: black;
        position: absolute;
        top: 50%;
        left: 50%;
        margin-top: -50px;
        margin-left: -550px;

    }
    .navbar{
        width: auto;
        height: 20px;
        position: absolute;
        right:0;
        top: 50%;
        margin-top: -10px;
        color: #fff;
    }
    .list{
        margin: 30px;
    }
    .list a{
        text-decoration: none;
        color: #fff
    }
</style>
</head>
<body>

<div class="nav">
    <div class="logo">
        <a href="#"><img src="http://climg.mukewang.com/58c0d2d900016ce303000100.png"></a>
    </div>
    <div class="navbar">
        <span class="list"><a href="#">课程</a></span>
        <span class="list"><a href="#">职业路径</a></span>
        <span class="list"><a href="#">实战</a></span>
        <span class="list"><a href="#">猿问</a></span>
        <span class="list"><a href="#">手记</a></span>
    </div>
</div>
</body>
</html>