This is the perfect gift for your girlfriend!
I created the box and the drawer using a Python script that writes svg-files. The tree was created from an image in Inkscape. The box is designed for 3mm MDF.
You can download the design files below or on Thingiverse:
First, assemble the main box using parts 1, 2, 3, 4 and 5. Slide the tree parts (12) into each other and fit them into the slots of part 1. Now we can assemble the drawer with parts 6, 7, 8, 9 and 10. Glue the handle parts (11) onto each other and fit them in the slot on the front panel of the drawer (8). Finally, the subdividers of the drawers can be assembled. Slide the parts a (13) into the parts b (14) and place the subdividers into the drawer.