A young cloud shepherd riding a fluffy flying creature races through a sky pasture where storm cloud

A young cloud shepherd riding a fluffy flying creature races through a sky pasture where storm clouds have broken loose and become giant stampeding animals made of thunder, he lassos a lightning ram, jumps between floating islands, surfs along a rainbow that bends under his feet and tries to herd the storm back toward a gigantic weather gate before it reaches a peaceful city below; cinematic fantasy 3D animation, soft sculpted cloud characters with expressive faces, huge aerial depth, fluid camera soaring through vapor, luminous sunrise, electric violet lightning, rainbow refractions, mist trails and sparkling rain droplets, whimsical yet epic atmosphere, ending with the shepherd whistling once as every storm creature suddenly transforms into gentle raincloud sheep and pours a perfect rainbow over the city.