UpsNDowns.html

<div m>
  <div></div>
  <div a></div>
  <div></div>
  <div b></div>
  <div></div>
  <div b></div>
</div>
<style>
  body {
    background: #62306d;
  }
  div[m] {
    width: 300;
    height: 200;
    position: relative;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    display: grid;
    grid-template-columns: auto auto auto;
  }
  div[a] {
    background: #f7ec7d;
    border-radius: 50% 50% 0% 0%;
  }
  div[b] {
    background: #f7ec7d;
    border-radius: 0% 0% 50% 50%;
  }
</style>