.fancybox-navigation .fancybox-button {
    border: 1px solid #ccc;
}

.fancybox-navigation .fancybox-button {
    border: 1px solid #888;
}

@media screen and (max-width: 800px) {
    .fancybox-navigation .fancybox-button {
        display: none;
    }
}