Apple 6 watch charging

when I put the watch on the charger it will show a lightning bolt - then the bolt is replaced by a dot. I am color blind and I don't know what color it is or what the dot is supposed to tell me? Does it change color from red to green perhaps to tell me when the watch is fully charged? As a color blind person I wish industry standards would stop using red and green for indices . I would much prefer they use red and blue which most of us can tell apart. ( or allow a user to select colors) For example yellow and red lights often are hard to tell apart , even green traffic lights. It would be better to have blue yellow and red but they will never change them.