I added some custom CSS to our Sphinx HTML builds to add thin grey lines above each class, method and function definition. I was finding it very hard to visually see where each block of documentation begins. You may need to blitz your documentation build directory for this to work.
If others don't like this, I can remove it. It gets the ball rolling on other CSS changes we want to make, though I suspect we want to keep them to a minimum, as the Sphinx defaults are already pretty good.
Science Software Branch
Operations and Engineering Division
Space Telescope Science Institute
Operated by AURA for NASA