<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>太极图</title>
<style>
*{
margin: 0;
padding: 0;
}
.box{
position: relative;
width: 240px;
height: 120px;
margin: 100px auto;
border-style:solid ;
border-width: 1px 1px 120px 1px;
border-radius: 50%;
animation: rot 2s infinite linear;
}
.box:before{
content: "";
position: absolute;
top: 50%;
left: 0;
width: 40px;
height: 40px;
background-color: #fff;
border-radius: 50%;
border: 40px solid #000;
}
.box:after{
content: "";
position: absolute;
top: 50%;
left: 50%;
width: 40px;
height: 40px;
background-color: #000000;
border-radius: 50%;
border: 40px solid #fff;
}
@keyframes rot {
0%{
transform: rotate(0deg);
}
100%{
transform: rotate(360deg);
}
}
</style>
</head>
<body>
<div class="box"></div>
</body>
</html>
