class Rouge::Theme

def self.palette(arg={})
  @palette ||= InheritableHash.new(superclass.palette)
  if arg.is_a? Hash
    @palette.merge! arg
    @palette
  else
    case arg
    when /#[0-9a-f]+/i
      arg
    else
      @palette[arg] or raise "not in palette: #{arg.inspect}"
    end
  end
end