As I explained on the other thread just now:
The way this logic is set up is you create Visibility Rules (in Form Editor) that show/hide a Rich Text area based on a Select field.
Then the Submit button's visibility is directly tied to the RT area's visibility.
Thank you again, Sanford. Have a good day
But you don't need to write any JS. That's the point of the recipe, the JS is always the same.
This can't be accomplished only with CSS. There's no CSS selector that will act on the vanilla form DOM properly.