PromptA single, elegantly folded white paper sail dominates the upper two-thirds of the frame, casting a subtle shadow onto the lower third. The surface beneath is a perfectly still, matte pale cerulean blue, suggesting calm water or polished stone. The lighting is soft, diffused daylight, creating gentle, smooth gradients across the paper's creases. The medium is high-detail digital painting, utilizing a restrained palette of white, pale blue, and faint grey shadows. The composition is centered, emphasizing the sail's sculptural form against the negative space of the blue field. Focus on the crisp texture of the paper. Wide 16:9 wallpaper; subject off-center, quiet low-contrast outer margins for desktop icons. Full-bleed artwork, no border, no frame, no text, no typography, no logos, no signature, no watermark.