What happens if you go over 30 minutes Citi Bike?

I'm curious, could you please explain what the consequences are if I exceed the 30-minute limit on a Citi Bike ride? Do I get charged extra? Is there a specific rate for every additional minute or a flat fee? And, is there a way to prevent being charged for going over the time limit, such as extending my ride through the app or finding a dock nearby to avoid additional costs? I'd appreciate any clarification you can provide on this matter.