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

.spinner {
  width: 24px;
  border-radius: 50%;
  height: 24px;
  border: 8px solid transparent;
  border-top: 8px solid #5cb85c;
  -webkit-animation: spin 1s linear infinite;
  animation: spin 1s linear infinite;
}