Darkness could be an absence of almost anything really. Absence of light, good, morals, God, etc. Most of those things would be associated with evil, though I suppose you could have an absence of morals that is just indifference. If good is caring for others, and evil is sacrificing others for your own benefit, then you could have an absence, with not actively seeking to harm others, but not going out of your way to help either.
The other way is to just change the perspective. For a dwarf,who lives their whole life underground, darkness isn't evil, but going up into the sun might be undesirable. Or in the game Hollow Knight, where the evil is "The Radiance", which is a being of light that wants to mind control and enslave everyone, and "The Void" is a living darkness that is being used to fight against it.