Sorry, this piece of code is untested.

foreach my $oWkS (@{$oBook->{Worksheet}}) {

     for(my $iR = $oWkS->{MinRow} ; defined $oWkS->{MaxRow} && $iR <= 
+$oWkS->{MaxRow} ; $iR++) {

          for(my $iC = $oWkS->{MinCol} ; defined $oWkS->{MaxCol} && $i
+C <= $oWkS->{MaxCol} ; $iC++) {

               $oWkC = $oWkS->{Cells}[$iR][$iC]; 

               my $Fill = $oWkC-{Format}->{Fill};
          }
     }
}
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$Fill will contain an array ref to a fill pattern.

According to the documentation:

$Fill->[0] = *Pattern*
$Fill->[1] = *Front Color*
$Fill->[2] = *Color*
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You can access other things like Border, Font, etc.

my $Border = $oWkC-{Format}->{BdrStyle};
my $Font   = $oWkC-{Format}->{Font};

. . . and so on
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