Add a visible clue to the screen to distinguish between Description, Limitations & Recommendations

As I scroll down the page of Descriptions or Recommendations, those headings disappear off the top of the screen. It would be helpful to have a visual clue (e.g., distinctive colour, or pattern) visible to me that stays visible during scrolling (e.g., either side border) to remind me which section (Description, Limitations or Recommendations) I'm in as I'm scrolling.