dark chocolate 90% is looking pale brown and not dark brown why

Question

I purchased 90% dark chocolate by AMUL India and kept in my car. on reaching home to my surprise the dark chocolate looked very brownish and the dark coating had nelted and accumulated in the botto of choc.Does dark chocolate-90% look so pale brownish. I thpught any dark choc above 75% would be dark brown fully and wholly. can anyone clear my doubt as i feel cheated by amul.