body {
  background-image: radial-gradient(#ffffff 20%, transparent 20%),
     radial-gradient(#ffffff 20%, transparent 20%);
  background-color: #9de0f2;
  background-position: 0 0, 50px 50px;
  background-size: 20px 20px;
  height: 200px;
  width: 100%;
}