at this time, you cannot make adjustments to the styles of the lightbox widget. But you can create your own lightbox interaction from scratch (I know not ideal, but doing it this way gives you ultimate control over your design):
Hope this helps 
at this time, you cannot make adjustments to the styles of the lightbox widget. But you can create your own lightbox interaction from scratch (I know not ideal, but doing it this way gives you ultimate control over your design):
Hope this helps