border-radius——圆、半圆、椭圆、角标

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div {
            background-color: pink;
            margin-bottom: 10px;
            font-size: 5px;
        }
        
        .c1 {
             30px;
            height: 30px;
            border-radius: 50%;
        }
        
        .c2 {
             60px;
            height: 30px;
            border-radius: 30px 30px 0 0;
            /* 这里不能写50%，宽高不同 */
        }
        
        .c3 {
             60px;
            height: 30px;
            border-radius: 30px/15px;
            /* 椭圆设置参数对应width/height的一半值---对应椭圆的水平半径，垂直长度半径 */
        }
        
        .c4 {
             30px;
            height: 30px;
            border-radius: 30px 30px 30px 0;
        }
    </style>
</head>

<body>
    <div class="c1">c1圆形</div>

    <div class="c2">c2上半圆</div>
    <div class="c3">c3椭圆</div>
    <div class="c4">c4角标</div>
    <div></div>
</body>

</html>