I went with black because I think it might stand out the most. However, I've skimmed through the comments and I agree also that if you can make the text, your image, the subscribe notification, and everything larger, that would be excellent. The way I would do it would be to just screenshot one of these ones that you have done, drop it in ChatGPT or Nano Banana, and then prompt it to enlarge the visuals. At the moment I would most likely use ChatGPT. I like all of the visuals that you have and the color scheme of all of the visuals that you have. If you could just get them bigger I think it'd be great.