feat(modal): uses n as CSS vars prefix

[timeTravelCYN]

ref #1842
close #1958

[vercel]

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[codecov]

Codecov Report

Merging #2007 (4f7610e) into main (055878c) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #2007   +/-   ##
=======================================
  Coverage   64.62%   64.62%           
=======================================
  Files         893      893           
  Lines       17472    17472           
  Branches     4143     4143           
=======================================
  Hits        11291    11291           
  Misses       5399     5399           
  Partials      782      782           

Impacted Files	Coverage Δ
src/modal/src/Modal.tsx	43.37% <ø> (ø)
src/modal/src/styles/index.cssr.ts	100.00% <ø> (ø)

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