spinner {
    -gtk-icon-source: -gtk-icontheme("process-working-symbolic");
    opacity: 0;
    transform: scale(0.8);
    transition:
        opacity duration("collapse") easing(),
        transform duration("collapse") easing();

    &:checked {
        animation: spin 600ms steps(12) infinite;
        opacity: 1;
        transform: scale(1);
        transition:
            opacity duration("expand") easing(),
            transform duration("expand") easing("ease-out-back");

        &:backdrop {
            opacity: 0.8;
        }

        &:disabled {
            opacity: 0.4;
        }
    }
}
