<div class="repeating-radial-gradient"></div>

.repeating-radial-gradient {
  background: repeating-radial-gradient(
    circle,
    rgb(151 71 255 / 0.5) 0 8.3333%,
    rgb(255 255 255) 8.3333% 16.6666%
  );
  background-size: 2rem 2rem;
  border-radius: 100%;
  height: 12rem;
  margin: 0 auto;
  width: 12rem;
}