.a-spinner {
    border: 8px solid #cdcdcd;
    border-radius: 50%;
    border-top: 8px solid #2196f3;
    width: 32px;
    height: 32px;
    box-sizing: border-box;
    animation: a_spinner_spin 2s linear infinite;
}

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