I'm a newbie, my CSS sign module is not working, and I can't drag and drop or sign documents.

I find the error at $o-font-size-base: o-to-rem(14px) !default; of web primary_variable.scss.

I tried to fix that by changing the $o-font-size-base: o-to-rem(14px) !default to $o-font-size-base: 0.875rem !default and it worked well.

However, I think I should not change the common module style, I want to find a good solution for that, and not change the common style

Why is the o-to-rem not working, which is the good solution for that?