.loading {
  position: relative;
  display: inline-block;
  width: 100%;
  padding-top: 100%;
}

.loading::after {
  content: ' ';
  position: absolute;
  display: block;
  width: 100%;
  height: 100%;
  top: 0;
  border-radius: 50%;
  border: 1px solid;
  border-color: currentColor transparent currentColor transparent;
  animation: loading 1.2s linear infinite;
}

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