Supernova

<div></div>
<style>
  body {
    background: #243d83;
    display: grid;
    place-items: center;
  }
  div {
    width: 120px;
    height: 120px;
    background: radial-gradient(circle at 50% 50%, #eeb850 30px, #243d83 31px);
    rotate: 45deg;
  }

  body:after,
  body:before {
    content: '';
    width: 220px;
    height: 100px;
    background: #6592cf;
    position: absolute;
    top: 50%;
    left: 50%;
    translate: -50% -50%;
    border-radius: 50px;
    z-index: -1;
    rotate: 45deg;
  }

  body:before {
    rotate: -45deg;
  }
</style>