老师，请帮忙看下代码结构和样式合理吗？

来源：4-6 自由编程

聪U

2020-11-18 22:38:16

结构：
<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Career Builder</title>
    <meta name="Keywords" content="职业生涯建设者">
    <meta name="description" content="职业生涯,职业规划,生涯建设,建设,职业">
    <link rel="stylesheet" href="css/index.css">
</head>

<body>
    
    <header>
        
        <div class="header-top">
            <div class="logo">
                
                <img src="images/logo.png" alt="">
            </div>
            
            <nav class="main-nav">
                <ul>
                    <li><a href="">HOME</a></li>
                    <li><a href="">ABOUT</a></li>
                    <li><a href="">GALLERY</a></li>
                    <li><a href="">FACULTY</a></li>
                    <li><a href="">EVENTS</a></li>
                    <li><a href="">CONTACT</a></li>
                </ul>
            </nav>
        </div>
    </header>
    
    <section class="banner">
        
        <div class="bg-img">
            <img src="images/banner3.jpg" alt="">
        </div>
        
        <div class="mask">
            <p>banner遮罩层</p>
        </div>
        
        <div class="ban-form">
            <form action="">
                <input type="text" placeholder="your Name" />
                <input type="tel" placeholder="your Phone" />
                <input type="email" placeholder="your Email" />
                <textarea placeholder="Write Your Comment Here"></textarea>
                <input type="submit" value="SEND MESSAGE" class="sub-mit">
            </form>
        </div>
    </section>
</body>
</html>
--------------------------------------------------------------------------------------------------------
样式：
* {
    margin: 0;
    padding: 0;
}
header {
    height: 80px;
    background-color: #07cbc9;
}
header .header-top {
    /* .header-top没有形成BFC,然后清除浮动 */
    width: 1200px;
    height: 80px;
    margin: 0 auto;
    /* background-color: yellow; */
    /* overflow: hidden; */
}
header .header-top .logo {
    float: left;
    width: 260px;
    height: 48px;
    padding: 16px 0;
}
header .header-top .logo img {
    width: 260px;
    height: 48px;
}
header .header-top .main-nav {
    float: right;
    padding-top: 30px;
}
header .header-top .main-nav ul {
    list-style: none;
    height: 30px;
}
header .header-top .main-nav ul li {
    float: left;
    line-height: 30px;
    margin-left: 20px;
}
header .header-top .main-nav ul li:first-child {
    margin-left: 0;
}
header .header-top .main-nav ul li a {
    display: block;
    padding: 0 10px;
    height: 30px;
    font-size: 16px;
    color: white;
    text-decoration: none;
}
header .header-top .main-nav ul li a:hover {
    background-color: yellow;
    color: purple;
}
/* banner部分样式 */
.banner {
    /* 相对定位，子绝父相 */
    position: relative;
    /* 不设置高度，也能撑开，因为图片img的height */
}
.banner .bg-img img {
    width: 100%;
    height: 600px;
}
/* 遮罩层效果样式 */
.banner .mask {
    /* 利用定位平铺在banner上 */
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 600px;
    background-color: rgba(0 , 0,  0, .3);

}
/* 表单层效果 */
.banner .ban-form {
    position: absolute;
    top: 100px;
    left: 50%;
    width: 504px;
    margin-left: -252px;
    /* 让文本居中，然后可以让input居中，submit按钮居中 */
    text-align: center;

}
.banner .ban-form input {
    height: 40px;
    border: 2px solid #808080;
    margin-bottom: 40px;

}
.banner .ban-form input,
.banner .ban-form textarea {
    width: 500px;
    background: none;
    outline: none;
    color: rgb(241, 29, 241);

}

.banner .ban-form textarea {
    height: 110px;
    border: 2px solid #808080;

}
.banner .ban-form .sub-mit {
    width: 200px;
    height: 40px;
    color: #808080;
    margin-top: 40px;
    cursor: pointer;
}