From the Dress Code section of FAQ’s:
During the day, dress is casual including shorts (if the season is warm), slacks or jeans and comfortable shoes for walking tours. Swimsuits, brief shorts, cover-ups and exercise attire should be reserved for the Fitness Center, pool areas and Sports Deck. There are no “formal nights” in the evening; evening dress is “elegant casual” for all dining venues, performances and special events. On these occasions, required attire for ladies includes a dress, skirt or slacks with a sweater or blouse; for gentlemen, trousers and a collared shirt. A tie and jacket are optional; jeans are not permitted. The evening dress excludes World Café where the dress remains casual after 6:00 PM.