feat(statistic):statistic uses n as CSS vars prefix

[XieZongChen]

ref #1842

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[codecov]

Codecov Report

Merging #1902 (2945a39) into main (75b4a2b) will decrease coverage by 0.00%.
The diff coverage is n/a.

❗ Current head 2945a39 differs from pull request most recent head c3a53da. Consider uploading reports for the commit c3a53da to get more accurate results

@@            Coverage Diff             @@
##             main    #1902      +/-   ##
==========================================
- Coverage   64.63%   64.62%   -0.01%     
==========================================
  Files         890      890              
  Lines       17404    17404              
  Branches     4127     4127              
==========================================
- Hits        11249    11248       -1     
  Misses       5377     5377              
- Partials      778      779       +1     

Impacted Files	Coverage Δ
src/statistic/src/Statistic.tsx	100.00% <ø> (ø)
src/statistic/src/styles/index.cssr.ts	100.00% <ø> (ø)
src/card/src/Card.tsx	82.05% <0.00%> (-2.57%)	⬇️
src/form/src/FormItemCol.ts	35.00% <0.00%> (ø)
src/form/src/FormItemRow.ts	31.57% <0.00%> (ø)
src/form/src/FormItemGridItem.ts	35.00% <0.00%> (ø)

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