YouTube video doesn’t not show on mobile

This is the first time I have used the function in the Customizer for TwentySeventeen to add the address for a YouTube video. My client was very happy to see the video on their desktop website, but not so happy to see that it picks up the header image on mobile, especially since it takes a crop of the image that is a butt on a bicycle seat.

Is there a way to get the video to play on mobile, as well?

The page I need help with: [log in to see the link]