Video on main page bug.

Hello!

I have a huge problem with setting up an video on a main page of theme.
Everything like images works perfect, except video.
When im trying to add video (with suitable resolution, size etc.) it is moving to the right side of main page, left becomes white. Like on the image:
https://ibb.co/ChjC84Y

When im trying to edit white background with theme opitons it is forwarding me to a description field.
Is it possible to set video on full screen?

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