Pop up Pro, cant get rid of space at bottom of pop up on mobile only

if you take a look at https://www.mindfulscience.es/dia-1a

a pop up should appear with a video in it, you will notice a large black space at the bottom. I cant get this to change color to white or just get this to adjust to the video height. Also if I turn the phone horizontal, I no longer have access to the volume controls..

help..

thanks

ej