Comment ajouter un pur CSS Charging Spinner

.loader {
  width: 100%;
  margin: 50px auto;
  align-items: center;
  border: 7px solid #f3f3f3; /* Light grey */
  border-top: 7px solid #3498db; /* Blue */
  border-radius: 50%;
  width: 100px;
  height: 100px;
  animation: spin 2s linear infinite;
}

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

<div class="loader"></div>
Stefano