.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid #000;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 16px;
    animation: spin 1s linear infinite !important;
}

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