Front title for cards

Hello

I created a flipbox with 13 cards in it, for services I want to sell, so I’d like to add a title to my cards so it’s easier to understand what it is.

When I use the “Front Description”, it’s kind of ugly because my images are not great with text on them, it’s hard to read.
I would like to create personalised images, with a title I would add on Photoshop or Indesign, but I need to know which size is optimum for it to be read properly?
I use the plugin in 3 columns each row, and I would like my text to be read on desktop but also on mobile…

Or else, is it possible to add a color band on the side 1 of the flipboxes, like underneath, to give it a title? Like with a new field?

Perdon my English, I hope you can understand my problem.

Thank you very much – Merci !