What chemical properties that allow for colour exist in the dark?
The chemical property that creates colour is the ability to absorb light of a specific visible wavelength. There is more than one way to do this.

Mostly colour is caused by the existence of electronic transitions in substances that match the energy of some wavelength of light so when light hits the substance, some is absorbed by exciting electrons from a lower to a higher energy level. The higher energy levels will not be populated unless there is some energy input to excite the electrons. But the structure that enables this absorption to exist is present whether or not there is any light.

There are other ways a substance can create colour. For example, some compounds do it by interference: the physical structure contains features that have the same scale as wavelengths of some colour of light. When light hits the substance the reflected light creates interference patterns that can selectively eliminate some wavelengths. This is why oil films on water show rainbow colours and why the mineral opal shows beautiful iridescence. again, though, the cause of colour is present whether there is light or not.

In short, the cause of colour is sometimes a chemical thing (involving electrons being excited) and sometimes a physical thing (involving interference) but, either way, the property that creates it exists even when there is no light.