How can I extend an image gallery to the edges of the "scribe" theme

Hello,

I wish to create a section in the homepage with an image gallery that expands to the edges of the website, like when I choose an image as a background configured as 100% wide.

I am using the "Justified Grid gallery". I tried different things, I tried also with "css hero" but I didn't get a solution. You can see the gallery in this url:

http://up3.eu/

(up3.eu must point to 52.28.74.145 in your host file)

I hope that's is possible to do.

Thanks in advance,
Marcel Odena