Wish I could help. I did a little searching, but I don’t know if the fawn in runners comes from the buff gene or the chocolate gene. And I suppose they carry the runner gene, but I don’t know much about it either.If I wanted to mKe black and whiterunners, how would I go about doing that? I thought if I paired a black with a fawn&white, I could get the black where the fawn is, but I guess it makes all sorts of other colors According to the calculator
I did find a nice site with some good pics and descriptions.
https://www.runnerduck.net/standard-colours.php