请老师检查，哪里需要改善？

来源：2-5 编程练习

SpecialMe

2020-09-15 21:59:30

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>IMOOC</title>
<style type="text/css">
*{
padding:0;
margin: 0;
}
.main{
width:1200px;
height:500px;
margin: 0 auto;
}
aside {
float: left;
width: 450px;
}
.main h1 {
font-size: 30px;
margin-bottom: 20px;

}
.main h1 samp{
font-size: 30px;
color: #7c7c7c;
}
.main > aside > dl {
position: relative;
display: block;
height: 75px;
margin-bottom: 25px;
}
.main > aside > dl > dt{
font-weight: bold;
font-size: 16px;
line-height: 16px;
text-decoration: underline;
position: absolute;
top: 0;
left: 90px;
}
.main > aside > dl > dd:first-of-type {
position: absolute;
top:0;
left: 30px;

background: url("http://climg.mukewang.com/582e61290001787900500051.png ") no-repeat;
height: 50px;
width: 50px;
color: #ffffff;
text-align: center;
line-height: 50px;
}
.main > aside > dl > dd:last-of-type {
position: absolute;
top:20px;
left: 90px;
}

article{
float: right;
width: 720px;
}
.main > article > p ,
.main > article > img
{
margin-bottom: 20px;
}
.main > article > p > img {
width: 100%;
height: 100%;
}
</style>
</head>
<body>
<section class="main">
<aside>
<h1>Recent <samp>Course</samp></h1>
<dl>
<dt>Hyper Text Markup language</dt>
<dd>1</dd>
<dd>That you are not alone, for I am here with you, though you are far away, I am here to stay.</dd>
</dl>
<dl>
<dt>Hyper Text Markup language</dt>
<dd>2</dd>
<dd>That you are not alone, for I am here with you, though you are far away, I am here to stay.</dd>
</dl>
<dl>
<dt>Hyper Text Markup language</dt>
<dd>3</dd>
<dd>That you are not alone, for I am here with you, though you are far away, I am here to stay.</dd>
</dl>
<dl>
<dt>Hyper Text Markup language</dt>
<dd>4</dd>
<dd>That you are not alone, for I am here with you, though you are far away, I am here to stay.</dd>
</dl>
</aside>
<article>
<h1>Welcome <samp>To massive Open Online Course</samp></h1>
<p>That you are not alone, for I am here with you, though you are far away, I am here to stay.</p>
<p><img src="http://climg.mukewang.com/582e61180001ede703300130.jpg"/></p>
<p>That you are not alone, for I am here with you, though you are far away, I am here to stay.</p>
<p>That you are not alone, for I am here with you, though you are far away, I am here to stay.</p>
</article>
</section>
</body>
</html>