<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style>
body{
background: #ccc;
}
#box{
width: 0px;
height: 600px;
border-left: 300px solid white;
border-right: 300px solid black;
border-radius: 600px;
}
#box::before{
content: '';
display: block;
width: 100px;
height: 100px;
border: 100px solid white;
background: black;
border-radius: 100%;
margin-left: -150px;
}
#box::after{
content: '';
display: block;
width: 100px;
height: 100px;
border: 100px solid black;
background: white;
border-radius: 100%;
margin-left: -150px;
}
</style>
</head>
<body>
<div id="box"></div>
</body>
</html>
