Give her a date. The best gifts, after all, are time spent together:) But, if you want to get her something else, I would suggest something you know she'll like, not just, like, a scarf YOU think is pretty. Think, "If I were a teenage girl..." So a scarf you think SHE would think would be pretty. You'll find something that she will love, I just know it. Good luck!
gift card to her favorite place and a date to that favorite place and she can pay for it lol jkin if she likes earrings or a heart necklaces your pic in one and her in another or 2 deferent pic in each slot of you 2 together