Wells full width content?

Site URL: https://www.philipparedding.co.uk/

Hi

I am trying to get the first page of this site to be full width. The gallery pages are working well but this page has a load of space on the right hand side and I cannot see how to shift it. The gallery pages fill up the entire space and I have tried adding a gallery with just the one image but it still has that empty space to the right. This image is 2000 px wide so it should be big enough to fill the space.

Any ideas would be much appreciated.

Add to Design > Custom CSS

div#canvasWrapper {
    max-width: 100%;
}