Font sizing for different screens

Design help Animations & Interactions
1

I figured out how to get div boxes containing images to size down on different screens and still stay centered, but the text over the image and div block won’t shrink on different screens. What should I do to fix that? I’ve tried making the text a percentage instead of in pixels and that didn’t work.

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2

Hi. Very general Q. Add link/screenshots or more details.

(Sets the font-size to a percent of the parent element’s font size)

https://www.w3schools.com/cssref/playit.asp?filename=playcss_font-size&preval=50%25

https://kyleschaeffer.com/development/css-font-size-em-vs-px-vs-pt-vs/