With indoor-outdoor seating and a busy after-work bar scene, the Barking Crab has something for everyone. Overlooking the Fort Point Channel in the increasingly corporate Seaport District, this is a casual place that’s close enough to the Boston Children’s Museum to attract families. Come here for simple fried, steamed, and broiled fish and shellfish, deftly prepared and served without any pretensions. Then look around and enjoy the contrasts of the waterfront: clam shack picnic tables and skyscrapers.