add background to photo-gallery sections / add a background to full site without breaks

Hey everyone,

I'd like to add a background to my full page. The gallery-sections don't allow a background to be added to my knowledge. 

I'd like it to look like when you add a background to a portfolio page (where even the header is included, making it seamless)

I tried it with this CSS code, but without luck.

here's the url for the background I'd like to use:

https://static1.squarespace.com/static/64d7868baa9e7a50d8612f97/t/66bca09a0923dc062dba76b3/1723637919971/texture.jpghttps://static1.squarespace.com/static/64d7868baa9e7a50d8612f97/t/66bca09a0923dc062dba76b3/1723637919971/texture.jpg

any help is very appreciated 🙂

Can you share page url? We can check easier