.loading {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  margin: auto;
  border: 10px solid rgba(0, 0, 0, .1);
  width: 100px;
  height: 100px;
  border-radius: 50%;
  border-left-color: #000;

  animation: spin 1s ease infinite;
}

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

  100% {
      transform: rotate(360deg);
  }
}