Why might my toy poodle have brown spots near the tip of feet?

First of all my toy poodle is white/her hair is all white.She has like caramel color streak at the near end of her feet where the hair is,she also has the same color of brown near her mouth.I was considering it to be just dirt,so i decide to wash her and it still seem to be there and everything.I was hoping for anyone to tell me the cause of this.Why might my toy poodle have brown spots near the tip of feet?
its stains.. the color around her mouth is stained from her saliva.. or the bacteria in the saliva.. the feet, ussually is from the dog licking the feet.. same reason- bacteria in the saliva causes staining.Why might my toy poodle have brown spots near the tip of feet?
Considering poodles can come in varieties of colors including phantom, piebald and parti-color, I'd imagine it's an apricot or chocolate colored marking. It may be a spot, or her coat in general may technically be that color, albeit extremely faded. An example are white huskies. Some all white huskies aren't actually all white, but have very, very pale red markings that can only be easily seen under the right lighting conditions.