I am an EU citizen and I got a tourist stamp upon arrival in Panama. From this answer I understand I can stay maximum 90 days in Panama. The linked source does not elaborate on the exact details around the 90 days.
If I were to leave and re-enter, would this reset the counter? If the 90 days are only within a specific timeframe, what is that timeframe (calendar year? 12 months? etc)? Or is this one of those cases where it is ambiguous and up to the officer at the border to decide?