This is a highly creative double exposure composite artwork that seamlessly blends a bustling city skyline with a deep underwater world. The background features a modern urban landscape, with the iconic Tokyo Skytree clearly visible, symbolizing the prosperity of human civilization. The foreground presents a clear blue seascape, where sunlight penetrates the water to create shimmering light patterns, and a school of fish swims among coral reefs. This visual technique of combining reality and illusion creates a surreal, dreamlike atmosphere, showcasing both the grandeur of the city and the tranquility of nature, perfectly interpreting the theme of harmony between 'nature and city'.