hello everyone! i just moved into a new apartment and the bathroom floor is stained with huge brown splotches from the previous tenants hair dye experiments. the flooring is vinyl. it appears as if these stains are inside the flooring, like they have receeded into the vinyl - and i am a bit nervous about bleach due to the lack of proper venalation in the bathroom - there's a fan - but no windows. any recomendations from stain/flooring experts? thanks!

-bess