fix(menu): prevent color override in css vars mode

[yggg]

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• I read and followed the CONTRIBUTING.md guide.
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Short description of what this resolves:

:host color style overrides color set in theme file.

[codecov]

Codecov Report

Merging #2201 into master will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #2201      +/-   ##
==========================================
+ Coverage   84.66%   84.67%   +0.01%     
==========================================
  Files         243      243              
  Lines        8478     8478              
  Branches      759      759              
==========================================
+ Hits         7178     7179       +1     
  Misses       1076     1076              
+ Partials      224      223       -1

Impacted Files	Coverage Δ
...endar-kit/services/calendar-month-model.service.ts	98.14% <0%> (+1.85%)	⬆️