For me it looks ok.
Most people will leave the bottom of the pan as-is or do light cleaning with dish soap and a "plastic" scrubbing pad.
Other people will use a product like Bar Keepers Friend to do a more in depth scrubbing.
The discoloration is from overheating the pan, not from stains. The actual metal has changed color through accidental tempering, so you won't be able to clean it off other than by grinding the metal down or re-tempering it (neither of which is a good idea).
The color won't significantly affect the performance of the pan. Just ignore it.