How are colors on cards determined?

[klauern]

I'm trying to figure out what makes cards show up as one color or another. There doesn't appear to be any documentation or explanation on how this is determined, or if you can configure it.

For instance, I would have thought that naming it in the same category would result in the same card color, but that doesn't appear to be the case.

[nirnaeth]

I know it's an old issue, but I think it's worth answering also for other people's sake: it depends on the type. A bug is black for example. A task is blue.

@mkloubert how do you feel about me updating the documentation?