Melanin is what presents the skin a tanned glance, but scars make it in uneven patches. An excessive amount melanin over the higher levels of skin results in hyperpigmentation. Ph?n s?n tai hay s?n s??n c?ng s? ???c g?t b?t ?? phù h?p v?i ??u m?i. Cu?i cùng s?n nhân t?o s?