Create a beautiful, fantasy city in an underwater world, maintaining a bright and magical style. Use white stone for the buildings and incorporate many corals throughout the city. The buildings should have silhouettes resembling shells. The city should be vibrant and enchanting, filled with colorful pink, blue, and purple corals. The atmosphere should be whimsical, with light shades and a lively, populated environment. --s 180 --ar 3:4 --niji 6