For a navigation section, I want it to use space-between
justification. For smaller displays where the navigation might have to wrap, I\'d like the items to center
LGSon's comment makes sense to me, but presumably OP wants the ability to modify dynamic text that may or may not fit in a container, regardless of flexbox config or media query.
Look into JS that detects line wraps, then triggers an action (e.g. centering the text).
For example: https://github.com/xdamman/js-line-wrap-detector
Or, JS that automatically resizes text to fit within a container. Useless for all kinds of situations.
For example: http://www.fittextjs.com