This is my problem: my body base background is set to dark blue, but the background of the back-end remains white. Since I use white text, it’s hard to change anything. If I change the background color of the block, the background image for the page doesn’t show anymore.
More info provides in the private info, as asked for.
That was a good idea. The site was made before blocks were available…
I have adjusted it now the way you described, and I think it all works fine now. Now I have to adjust some things on mobile 🙂
Thank you for your help!