"Create a colorful and engaging YouTube thumbnail featuring a cheerful cartoon-style shark swimming joyfully in the ocean. The shark has a light blue skin tone, a smooth, rounded body, and a large, friendly smile. It should be surrounded by vibrant coral reefs and small, colorful fish. Include musical notes floating around to indicate singing and fun. The background should be bright and lively, with rays of sunlight filtering down from the surface. Use bold and playful fonts to add the title ‘The Singing Shark’ prominently on the thumbnail, making it eye-catching for children, --ar 16:9