Although that might not be the case here,
grey as a color with zero saturation may seem to have the same shade
as the nearest color with at least some saturation.
Say, grey background plus a couple of elements one might call brown —
and the background may seem brownish.
A couple of blueish themes I know of:
https://stash.reaper.fm/theme/1945/J...inted_v104.zip
and
https://stash.reaper.fm/theme/2004/ReAerah.rar