koi fish frolicking among octopuses and fish and coral and seahorses in the romantic courtyard of an underwater baroque white marble cathedral with stained glass windows. neon light, masterpiece 4 k digital illustration by ruan jia and mandy jurgens and william - adolphe bouguereau, award winning, artstation, gustave dore'background, intricate details, realistic, panoramic view, volumetric lighting, hyperdetailed, 8 k resolution, golden hour, intricate art nouveau, smooth, sharp focus, rendered in unreal engine 3