I have a tablet mounted on the wall which displays different kinds of stuff, like weather conditions and forecasts and so on. Among this is the time of civil d

I have a tablet mounted on the wall which displays different kinds of stuff, like weather conditions and forecasts and so on. Among this is the time of civil dawn, because at this time I don't want to be riding bike anymore since it's getting dark (and colder). Next to it is a countdown timer with an offset of minus two hours, since I do ride my bike around 1 to 1.5 hours. So when I see that this timer is reaching 0, I know that I'm at my last opportunity to go for a bike ride that day. Once it reaches 0, it shows the countdown to the correct, non-offsetted time of civil dawn, but in another color, so that I know that I still have time to make a shorter ride. I barely look at the time of dawn, since the countdown timer is so much more informative for me. It let's me know how many hours or minutes I still have to do things.