It's difficult to tell from the pictures but i'm going to go against the grain and say brown. I see lightened areas on the flank on both pictures and a slightly lightened muzzle on the top photo.
I'd like to see pictures taken from the side and perhaps pictures showing the muzzle and flank more clearly.
The lightened areas are caused by sweat. Here is my friends black Percheron cross, this horse is black I actually owned this horse for a before selling to my friend. He gets used a lot and gets sweat lightened areas. Heck by late summer a lot of his coat gets lightened from sun and sweat.