def lighten_color(hex_color, amount=0.6)
      hex_color = hex_color.gsub('#', '')
      rgb = hex_color.scan(/../).map { |color| color.hex }
      rgb[0] = [(rgb[0].to_i + 255 * amount).round, 255].min
      rgb[1] = [(rgb[1].to_i + 255 * amount).round, 255].min
      rgb[2] = [(rgb[2].to_i + 255 * amount).round, 255].min
      "#%02x%02x%02x" % rgb
    end
def lighten_color(hex_color, amount=0.6)
      hex_color = hex_color.gsub('#', '')
      rgb = hex_color.scan(/../).map { |color| color.hex }
      rgb[0] = [(rgb[0].to_i + 255 * amount).round, 255].min
      rgb[1] = [(rgb[1].to_i + 255 * amount).round, 255].min
      rgb[2] = [(rgb[2].to_i + 255 * amount).round, 255].min
      "#%02x%02x%02x" % rgb
    end
Amount should be a decimal between 0 and 1. Higher means lighter