adjusted font size when zooming in & out

When using maps, capital cities for example can be read when utterly zoomed in but also when zooming out to continent level. We are working with rather complex workflows, which require us to zoom in and out like a map. To keep a better overview and quicker understanding and orientation, we wished very much that there was a setting, where we could set “capital city boxes” that can be read in close view as also from the “continental” view. Just setting one large font would not sort this as this would be too big for the close view. It would need to readjust with zooming in and out. Thank you!