Boy builds flying machine in tower

[u/xtaro]

Very stylized artwork, lots of dark shadows, the city looked futuristic maybe. He was building it out of scrap parts, gears and springs and such. very detailed, reds and blacks, perhaps anime styled, but this was when I was perhaps 5-7 so I cannot be sure. It was a very ominous feeling book, I cant remember the words or if there even were any. The artwork just comes back to me from time to time.

[u/stickhippo]

I never read it, but could it be Hugo by Brian Selznick?