<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>css 转圈</title>
<style>
.turn{
position: relative;
width:100px;
height: 100px;
border: 10px solid #f4f4f4;
animation:turn 1s linear infinite;
margin: 100px auto;
border-radius: 50%;
}
.turn::after{
position: absolute;
content: '';
top:0px;
left:10px;
width: 12px;
height: 12px;
background: #333;
border-radius:50%;
更多请见：http://www.mark-to-win.com/tutorial/50954.html