# File lib/gruff/base.rb, line 401
    def theme_greyscale
      # Colors
      @colors = [
          '#282828', # 
          '#383838', # 
          '#686868', # 
          '#989898', # 
          '#c8c8c8', # 
          '#e8e8e8', # 
        ]
      
      self.theme = {
        :colors => @colors,
        :marker_color => '#aea9a9', # Grey
        :font_color => 'black',
        :background_colors => 'white'
      }
    end