Making banner image fully visible in Brine

Site URL: https://interiorsbydesignco.squarespace.com/

Hi,

I've recreated a clients site from 7.1 to Brine in 7.0 so that they can have a parallax background image with scrolling text.

I've added anchor text links to jump to text block and used spacer block and also carriage returns to get the positioning right.

I want to stop the banner image to scale beyond the edges, so that the background image is always 100% of its width. Is this possible?

To view the site:

https://interiorsbydesignco.squarespace.com/

interiorsbydesign

Now that I've added in the spacing the banner image is scaling bigger and isn't what the client wants.

I hope this is a straight forward fix as the anchors jump to the right section.

Also, the parallax effect in Safari is pretty jumpy but scrolls smoothly in Chrome? Is this a known issue?

Many thanks in advance :0).