runde Ecken in Variationen

HTML

<div class="box rund1"></div>
<div class="box rund2"></div>
<div class="box rund3"></div>

CSS

body {padding: 20px 40px;}
.box {
    background: #a20000;
    width: 400px;
    height: 100px;
    margin-bottom: 50px;
}

.rund1 {
    border-radius: 20px;
}

.rund2 {
    border-radius: 20px/60px;
}

.rund3 {
    border-radius: 20px 40px / 10px 20px;
}