.masterstudy-buy-button__link {
    border-radius: 60px !important;
    overflow: hidden !important; /* aseguramos que los hijos no sobresalgan */
}

.masterstudy-buy-button__link *,
.masterstudy-buy-button__link:hover * {
    border-radius: 60px !important;
}

.masterstudy-buy-button__link:hover {
    background-color: #333333 !important;
    color: #ffffff !important;
    border-radius: 60px !important;
}