- The Costa has been a best seller since day one. It's the airy shirt you want for the warmest days of the year. - Made with light-as-air organic cotton gauze — a little wrinkle is part of the charm. - Roll up the sleeves and unbutton a few for that effortless, coastal look we love. - Once you treat yourself to one, you’ll want every color. - Matte mother-of-pearl buttons.