it might be that she's sitting on her wee :wave: does she have a particular place for peeing? buttons loves to sit in the littertray so consequently her feet are sometimes a bit mucky.
sawdust causes respiratory issues, not worth the risk in my opinion. You could try something like megazorb or even vet bed instead (with hay for eating). Most bunnies have a bit of discolouration to their paws, it's normal and not a problem
i just didnt want it too get to bad that the urine starts effecting the fur on her feet, im always like this with my animals so try to prevent health issues.is vet bed expensive ?