I ran out of ideas at the same place, it looks like there's a panel by the door where we should be able to enter a code but it isn't doing anything for me.
Thank you for the compliments on my game! This is my first attempt at pixel art, so it's awesome to hear someone loves it.
And I'm happy to see you were able to get past the part you were stuck on! I do plan to do some more audio balancing once the jam voting periods end that should help a bit, especially with the bookshelf puzzle.
Oh, and, it is intentional that the drawers don't have visual feedback, I just didn't have enough time to add that in, so they only use audio cues.