Many thanks. Some follow‑up.
@merefield: your example worked when added as follows:
☰ ▸ Admin ▸ Customize ▸ Themes = Default ▸ Edit CSS/HTML ▸ Desktop ▸ CSS
@awesomerobot: I could not get your code to work, despite trying some variations.
Note that first example is site‑wide and the second example is (or rather should be) per‑image.
Any further suggestion welcome. The site‑wide solution is acceptable but a per‑image application is probably preferable.
PS: the AI captioning is deteriorating with every iteration 