海龟穿行珊瑚礁

A green sea turtle glides through a vivid coral reef, small fish scattering and re-forming in its wake as its flippers sweep slow and deliberate. The camera drifts alongside at the turtle's pace, keeping it frame-right. Clear turquoise water, god-rays fanning down from the rippled surface, saturated coral pinks and oranges, tiny particles catching the light. Nature-documentary clarity, 50mm, crisp focus. <muffled underwater ambience, soft bubble trail>. No music.