what do the colours in a chinese shadow puppet mean?

The colors reflect the figure's characteristics. Take Guan Yu for example, his clothes are green. For Zhang Fei, he is always in black. If it is an emperor, then golden and yellow are his colors.

If you look at the puppets carefully, you will find that some of them have different colors in face. Red face usually symbolizes loyalty and bravery. Black face means that this figure is
upright and outspoken. Green face indicates the figure is a hero of the greenwood. Or it could be a ghost too.