Elbow

<div></div>
<style>
  body {
    background: #6592cf;
    display: grid;
    place-content: center;
  }
  div {
    width: 250px;
    height: 150px;
    border-radius: 100px 0 0 0;
    border-top: 50px solid #060f55;
    border-left: 50px solid #060f55;
  }
</style>