用div+css生存太极图案

css代码

body{
    background: gray;
    }
        #test4{
            width: 0px;
            height: 600px;
            border-left: 300px solid white;
            border-right: 300px solid black;
            border-radius: 600px;
        }
        #test4::before{
            content: '';
            display: block;
            width: 100px;
            height: 100px;
            border: 100px solid white;
            background: black;
            border-radius: 100%;
            margin-left: -151px;
        }
        #test4::after{
            content: '';
            display: block;
            width: 100px;
            height: 100px;
            border: 100px solid black;
            background: white;
            border-radius: 100%;
            margin-left: -151px;
        }
    </style>

html代码

<div id="test4"></div>