Witch Universe
Magical. Dark magic (witches) isn’t inherently evil, more than it is simply a name for a section of magical proficiencies. Light magic (fairies) isn’t inherently good so much as it is a name for a type of magic. Mermaids are basically water benders, and Spirits are healers. The more saturated the color of hair, the more powerful and the less saturated the less powerful. Hair will only turn white from lack of power if there was magic present before; if a person simply lacks a magical ability, their hair will be a “natural color” such as brown or blonde or red/orange.
Fantasy in simplest terms. It could also be sci-fi in a rural area, largely in heavily vegetative areas.