.single_add_to_cart_button.kpc-loading,
button[name="update_cart"].kpc-loading,
.configurator-add-to-cart.kpc-loading {
    opacity: 0.5;
    cursor: not-allowed;
}
.kpc-loading-icon {
    display: inline-block;
    width: 1em;
    height: 1em;
    border: 2px solid rgba(0,0,0,.1);
    border-top-color: #000;
    border-radius: 50%;
    animation: kpc-spin 0.5s linear infinite;
}
@keyframes kpc-spin {
    to { transform: rotate(360deg); }
}