Finsweet Client-First REM for Padding

I have a question for anyone using Client-first structure.

In the setup structure Finsweet advises to use REM units for global page padding.

Will that effect negatively on layouts if a user has their browser set to a higher text pt size?
For example, if I use 4 rem for left and right padding. Will the padding increase with the user who upsizes browser default settings? Wouldn’t that lead to too much padding on phone for example?wouldn’t REM be useful for only typography?

Any technical insight on why they suggest REM for global padding would help me understand the approach better.

Thanks!


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