Mountains

<div>
  <p></p>
</div>
<style>
  body {
    background: #293462;
    display: grid;
    place-content: center;
  }
  div {
    width: 200px;
    height: 200px;
    background: #fff1c1;
    border-radius: 50%;
    overflow: hidden;
  }

  p {
    height: 150px;
    width: 150px;
    background: #fe5f55;
    translate: 67px 90px;
    rotate: -45deg;
    margin: 0;
    box-shadow: -129px -30px #fe5f55;
  }
</style>