Why does vitamin B2 (riboflavin) turn my pee neon green

I drink an amp energy every morning and I noticed my first pee of the morning is extremely neon green. I couldn't figure out what was causing it based on the ingredients until I narrowed it down to B2, but B2 is a pretty standard vitamin so I don't understand how it's causing this.

Side note: I think it's cool, B2 whatever you're doing, so long as you're not killing me, keep it up 👍