老师您好，是否有可以优化的地方，感谢！

4-8 自由编程

about区域布局效果的实现需要使用浮动和定位，前面我们已经学习过了这两个知识点，接下来让我们参考效果标注图，完成这部分的布局吧~

CSS相关代码：

*{
margin: 0;
padding: 0;
}
header{
height: 80px;
background-color: #07cbc9;
}
header .header-top{
width: 1200px;
margin: 0 auto;
text-align: center;
overflow: hidden;
}
header .header-top .logo{
float: left;
height: 48px;
padding-top: 16px;
color: white;
}
header .header-top nav{
float: right;
}
header .header-top nav ul li{
float: left;
list-style: none;
font-size: 16px;
color: white;
margin: 10px;
padding-top: 20px;
}
.banner{
position: relative;
width: 100%;
height: 600px;
top: 0;
}
.banner img{
width: 100%;
height: 600px;
}
.banner .cover{
position: absolute;
top: 0;
width: 100%;
height: 600px;
background:rgba(0, 0, 0, 0.5)
}
.banner form{
position: absolute;
top: 100px;
left: 50%;
margin-left: -252px;
width: 504px;
height: 350px;
color: #808080;
/* 给form标签添加text-align:center;属性，让按钮水平居中显示 */
text-align:center;
}
.banner form .form-box{
width: 504px;
height: 40px;
margin-bottom: 20px;
/* 除表单元素的背景颜色 */
background: none;
border: 1px solid #808080;
}
.banner form textarea{
width: 504px;
height: 110px;
/* 除表单元素的背景颜色 */
background: none;
border: 1px solid #808080;
}
.banner form .submit-btn{
width: 200px;
height: 40px;
margin-top: 10px;
text-align: center;
/* 除表单元素的背景颜色 */
background: none;
color: #808080;
border: 1px solid #808080;
}
.about{
width: 1200px;
margin: 0 auto;
margin-top: 30px;
}
.about .about-top{
width: 1200px;
}
.about .about-top h2{
font-size: 32px;
text-align: center;
}
.about .about-top .about-underline{
width: 60px;
height: 3px;
background-color: #07cbc9;
margin: 10px auto;
}
.about .about-top .about-intro{
width: 440px;
height: 60px;
font-size: 14px;
color: grey;
text-align: center;
margin: 0 auto;
}
.about .about-content{
position: relative;
width: 1200px;
height: 465px;
overflow: hidden;
}
.about .about-content .about-us{
float: left;
width: 341px;
height: 362px;
}
.about .about-content .about-us h3{
float: left;
font-size: 28px;
margin-top: 20px;
}
.about .about-content .about-us .about-article{
position: absolute;
float: left;
top: 50%;
margin-top: -103px;
width: 300px;
padding: 20px;
font-size: 18px;
border: 1px solid grey;
background: rgba(255, 255, 255, 0.5);
}
.about .about-content .about-us .about-article .btn-explore{
width: 140px;
height: 40px;
background-color: black;
color: white;
text-align: center;
line-height: 40px;
margin-top: 25px;
}
.about .about-content .about-pic {
float: left;
margin-top: 30px;
margin-left: -72px;
width: 650px;
height: 435px;
}
.about .about-content .faculty-stdnt-num{
float:right;
right: 0;
margin-top: 30px;
width: 260px;
height: 338px;
}
.about .about-content .faculty-stdnt-num .student-num{
float: right;
width: 260px;
padding-top: 40px;
padding-bottom: 40px;
margin-bottom: 30px;
text-align: center;
border: 1px solid #07cbc9;
}
.about .about-content .faculty-stdnt-num .student-num .r1{
font-size: 20px;
font-weight: bold;
}
.about .about-content .faculty-stdnt-num .student-num .underline{
width: 45px;
height: 3px;
background-color: #07cbc9;
margin: 10px auto;
}
.about .about-content .faculty-stdnt-num .faculty-num{
float: right;
width: 260px;
padding-top: 40px;
padding-bottom: 40px;
text-align: center;
border: 1px solid #07cbc9;
}
.about .about-content .faculty-stdnt-num .faculty-num .r1{
font-size: 20px;
font-weight: bold;
}
.about .about-content .faculty-stdnt-num .faculty-num .underline{
width: 45px;
height: 3px;
background-color: #07cbc9;
margin: 10px auto;
}

HTML相关代码：

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<link rel="stylesheet" href="css/css.css">
</head>
<body>
<!-- 页面头部 -->
<header>
<div class="header-top">
<!-- 网页的logo -->
<div class="logo">
<h1>Career Builder</h1>
</div>

<!-- 网页的导航条 -->
<nav>
<ul>
<li>HOME</li>
<li>ABOUT</li>
<li>GALLERY</li>
<li>FACULTY</li>
<li>EVENTS</li>
<li>CONTACT</li>
</ul>
</nav>
</div>
</header>

<!-- 网页的banner -->
<div class="banner">
<img src="images/banner3.jpg">
<div class="cover"></div>
<form action="save.php" method="post">
<p>
<input class="form-box" type="text" placeholder="your Name">
</p>
<p>
<input class="form-box" type="text" placeholder="your Phone">
</p>
<p>
<input class="form-box" type="email" placeholder="your Email">
</p>
<p>
<textarea cols="50" rows="10" placeholder="Write Your Conment Here"></textarea>
</p>
<input class="submit-btn"type="submit" value="SEND MESSAGE">
</form>
</div>

<!-- about区域 -->
<div class="about">
<div class="about-top">
<h2>ABOUT</h2>
<div class="about-underline"></div>
<div class="about-intro">Dorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s</div>
</div>
<div class="about-content">
<div class="about-us">
<h3>A WORD<br/>
ABOUT US
</h3>
<div class="about-article">
<p>
Praesent dignissim viverra est,sed bibendum ligula congue non.
Sed ac nisl et felis gravida commodo? Suspendisse eget ullamcorper ipsum.
Suspendisse diam amet
</p>
<div class="btn-explore">EXPLORE</div>
</div>
</div>
<div class="about-pic">
<img src="images/bb3.jpg">
</div>
<div class="faculty-stdnt-num">
<div class="student-num">
<div class="r1">70000</div>
<div class="underline"></div>
<p>Students</p>
</div>
<div class="faculty-num">
<div class="r1">600</div>
<div class="underline"></div>
<p>Faculty</p>
</div>
</div>
</div>
</div>
</body>
</html>