We've seen folks wear all sorts of 'interesting' attire at both places, but it's typically 'resort dress'. In other words, you don't need to wear coat/tie or evening dresses, but nice slacks/pants and buttoned top seems more appropriate. You might feel slightly out of place in shorts and T's. I usually sport khakis w/ a short sleeved Polo dress shirt and the Chief will wear nice Capris with a bottoned blouse.