Nice work! It looks like there are the components for a pretty interesting game here.
I played on Linux using Proton, so that means your game is SteamDeck ready ;)
I did notice it didn't cope terribly well with being full-screened... not sure why, but the menus at least got a bit confused by that and stopped registering clicks.
I belatedly discovered you could scroll-wheel through the different coloured blocks in the first position on the UI, but that didn't appear to change anything... maybe I just didn't click middle mouse?
The _fusion reactor_ or _flux capacitor_ is pretty, and must have been satisfying to build!
Nice work, hope you learned a ton and look forward to seeing what you turn this into.