.spin {
  position:relative;
  display: block;
  width: 90px;
  height: 90px;
  margin-left:auto;
  margin-right:auto;
}
.spin:after {
  content: " ";
  display: block;
  width: 64px;
  height: 64px;
  margin: 8px;
  border-radius: 50%;
  border: 6px solid #000000;
  border-color: #000000 transparent #000000 transparent;
  animation: spin 1.2s linear infinite;
}

.spin.hidden{display:none}

@keyframes spin {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}