code: def run
        # pre-set light color to avoid green at low brightness
        @lights.set_color("brightness:#{start_brightness} kelvin:#{start_temperature}", duration: 0, power_on: false)
        @lights.set_color("brightness:#{end_brightness}", duration: half_sunrise_time)
        sleep(half_sunrise_time)
        @lights.set_color("kelvin:#{end_temperature}", duration: half_sunrise_time)
      end
docs: warning: this method takes half the sunrise time to execute