.wordfest-vimeo-desktop {
    display:block;
    height: auto;
}

.wordfest-vimeo-mobile {
    height: auto;
    display:none;
}
@media only screen and (max-width: 767px) {
    .wordfest-vimeo-mobile {
        display:block;
        height: calc(100vw* .55);
    }
    .wordfest-vimeo-desktop {
        display:none;
    }
}