Business casual is appropriate for this restaurant. Where I work business casual is defined as follows:
Pants
Appropriate: khakis, chinos, "Dockers" style gabardines, flannels, linen or cotton pants, dress slacks.
Inappropriate: Denim of any kind or color, capri pants, cut-offs, sweat pants, running suits, skorts, shorts, overalls, spandex, or leggings.
Shirts
Appropriate: Casual shirts with collars, golf or polo-style shirts, sweaters, turtlenecks, blouses, and knit tops.
Inappropriate: T-shirts, tank tops, crop tops, sweatshirts, sports jerseys and halter tops.
Dresses and Skirts
Appropriate: Casual dresses and skirts with stockings.
Inappropriate: Sundresses or other revealing dresses (shoulders must be covered), or anything that looks unprofessional.
Footwear
Appropriate: Loafers, flats, boots, dress sandals with back straps, leather deck shoes.
Inappropriate: Athletic shoes, "flip-flops" and sneakers.
I do think that capri's are fining for dining at most WDW restaurants.

And stockings certainly do'nt need to be worn
Anne