feat(icon): uses n as CSS vars prefix

[ahwgs]

ref #1842
close #1990

[vercel]

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[codecov]

Codecov Report

Merging #2004 (6853799) into main (3bb4fa0) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #2004   +/-   ##
=======================================
  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/icon/src/Icon.ts	90.47% <ø> (ø)
src/icon/src/styles/index.cssr.ts	100.00% <ø> (ø)

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