body, div {
  background-image: -webkit-repeating-radial-gradient(center center, #ccc, #ccc 0.2rem, transparent 0.2rem, transparent 100%);
  background-image: repeating-radial-gradient(center center, #ccc, #ccc 0.2rem, transparent 0.2rem, transparent 100%);
  background-size: 0.8rem 0.8rem;
  background-position: center;
}

div {
  position: fixed;
  top: 50%;
  left: 50%;
  margin-top: -200vmax;
  margin-left: -200vmax;
  height: 400vmax;
  width: 400vmax;
  background-size: 0.8rem 0.8rem;
  -webkit-animation: woop 240s infinite linear;
          animation: woop 240s infinite linear;
}

@-webkit-keyframes woop {
  to {
    -webkit-transform: rotate(1turn);
            transform: rotate(1turn);
  }
}

@keyframes woop {
  to {
    -webkit-transform: rotate(1turn);
            transform: rotate(1turn);
  }
}