<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style>
.shadow {
box-shadow:5px 5px 5px red;
200px;
height: 100px;
background-color: blue;
border-radius: 50%;
text-align:center;
}
.radius {
200px;
height: 200px;
border: 1px;
background-color: red;
border-radius: 50%;
text-align:center;
}
</style>
</head>
<h1>我是标题</h1>
<p>我是段落</p>
<body>
<div class="shadow"> <!--box-shadow 设置阴影属性，阴影右水平偏移,垂直下偏移，模糊半径,阴影基本颜色-->
测试
</div>
<div class="radius"> <!--border-radius 用来创建圆角-->
</div>
</body>
</html>