Interpreting blast-radius Graphs

I just ran a Terraform project graph and displayed it on blast-radius the first time. Does anyone know if the use of the colors in the blocks is consistent across projects? Is there is a URL with a key or legend for how to interpret the colors? Or, does it just vary from project to project and we need to figure it out as we go?

There’s some doc here https://28mm.github.io/blast-radius-docs/.