iirc, the books are very ambiguous about the nature of magic in Westeros. A lot of the things that the show very non-chalantly depicts as magic seems a lot more up for debate in the books and could be merely some sort of parlor trick. Arya turning blind, for instance, was the effect of some sort of potion that she drank, not that weird "eyes get cloudy from a curse" shtick from the show. Melissandre comes to mind as well. The books have her do things and describe them in a manner that make both mundane and magical explanations reasonable.
A lot of stuff is implied or never really described either. For all we know, Greywater Watch could just be a big fucking tent that the crannogmen pull down and relocate every now and then, or it's a bunch of boats tied together that move around in the swamps. It's not said to be Howl's Moving Castle, that stomps around on giant legs, that's for sure.
I think Martin was deliberately obtuse with a lot of things, like with prophecies that are never spelled out to be taken this way or that way, it's always a bunch of characters interpreting them however way they like and every single interpretation is just as valid as the others. Dumb and Dumber don't understand that concept, you can almost hear how they go "This even is to be taken this exact way, it's magic... this old fool of a bookworm Martin, he really dropped the ball by not making it more clear! Thankfully he's got us to fix that issue!"
Of course, birthing assassin-shadows, bringing people back to life and so on, that's undeniably supernatural and the creation of wildfire seems to rely on some sort of spell, too. An alchemist remarks that they have a much easier time creating wildfire and it's as if the magic in Westeros grew stronger, so there is some undeniable magic going on, but it's just a fraction of what the show just goes "lol magic, I ain't gotta explain shit" on.