#basebar span {
    @media only screen and (max-width: 349px) {
        font-size: calc(15px*var(--topbars_size_fraction_for_under_350px_wide_screens));
    }
    @media only screen and (min-width: 350px) and (max-width: 575px) {
        font-size: calc(15px*var(--topbars_size_fraction_for_350px_through_576px_wide_screens));
    }
    @media only screen and (min-width: 576px) and (max-width: 767px) {
        font-size: calc(15px*var(--topbars_size_fraction_for_576px_through_767px_wide_screens));
    }
    @media only screen and (min-width: 768px) {
        font-size: 15px;
    }
}