A Folded Shadow in a Glass Envelope

Generate exactly one finished image, never a collage, grid, or multiple variants. An envelope sculpted from thin transparent glass rests on a pale blue desk; inside is a folded shadow shaped like a letter, visible through the material. Oblique afternoon sunlight, optical edges and believable contact shadow, two small air bubbles, minimal gallery photography. Square, no lettering. Original visual concept, carefully resolved composition and materials. No watermark. Text-to-image only; do not use previous conversation images as visual inputs.