fix: rename @gray-11 to @popover-background

[ycjcl868]

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[codecov]

Codecov Report

Merging #20130 into 4.0-prepare will not change coverage.
The diff coverage is n/a.

@@             Coverage Diff              @@
##           4.0-prepare   #20130   +/-   ##
============================================
  Coverage        97.56%   97.56%           
============================================
  Files              294      294           
  Lines             7237     7237           
  Branches          1992     1962   -30     
============================================
  Hits              7061     7061           
  Misses             176      176

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