use Data::Dumper;

my %colorhash = ( CCgray  => [ "0","0","0" ],
                  CCwhite => [ "1","0","0" ],
                  CCgrey  => [ "0","2","0" ],
                  CCBlue  => [ "0","0","3", ] );

my @light2dark = sort numsort (keys %colorhash);

print Dumper \@light2dark;

sub numsort {
    $colorhash{$a}[0] <=> $colorhash{$b}[0]
 or $colorhash{$a}[1] <=> $colorhash{$b}[1]
 or $colorhash{$a}[2] <=> $colorhash{$b}[2];
}