.t-popup__container {
    border-radius: 15px !important;
}

    .tn-elem__4966343301664765561793 iframe {
        border-radius: 30px !important;
    }
    
    @media (max-width: 960px) {
        .tn-elem__4966343301664765561793 iframe {
            border-radius: 20px !important;
        }
    }