PHASE 1: VISUAL DECONSTRUCTION - **Fabric Physics:** The source garment appears to be a cotton poplin or crisp cotton blend. It possesses medium stiffness with low elasticity. Unlike the user's current flowy floral top, this material holds its shape. It should not cling tightly to the skin but rather structure itself around the torso. It has a matte finish and should not exhibit specular highlights (shine) but rather soft, diffuse reflection. - **Key Features:** The sharp, structured collar points, the central button placket (which must remain straight but follow the torso's curvature), the sleeveless armhole hems, and the subtle darting at the bust must be preserved. The curved bottom hemline is critical. PHASE 2: FIT & DRAPE SIMULATION - **Body Mapping:** Due to the user's pose (leaning backward against a railing with arms extended), the garment must follow gravity, hanging vertically rather than following the backward slant of the torso. This will create a slight gap between the fabric and the lower abdomen. The collar must sit naturally around the neck base, not floating. **Crucial:** Since the target is wearing sleeves and the source is sleeveless, the simulation must accurately inpaint/generate the user's upper arms with matching skin tone and muscle structure. - **Occlusion Handling:** The horizontal metal railing in the foreground significantly occludes the lower hip/hem area of the garment. The shirt must be rendered *behind* the railing. The user's hands are on the railing and away from the torso, so hand occlusion is minimal, but the shirt's armholes must not intersect with the shoulder joints. PHASE 3: ENVIRONMENT & LIGHTING - **Light Match:** The user is in a large indoor atrium with diffuse daylight coming from high clerestory windows (top-down, cool-toned) mixed with background artificial signage (warm). The white shirt must not appear "studio bright"; it needs to adopt the ambient ambient occlusion of the mall, picking up subtle grey/blue tints from the metal structure and floor. Shadows should be soft and cast downward from the collar onto the clavicle area. - **Color Calibration:** The source white is neutral/cool. It must be warmed slightly to match the target image's white balance to avoid looking like a "sticker." The brightness levels must be lowered to match the exposure of the user's jeans and current skin lighting. PHASE 4: IDENTITY PROTECTION - **Facial Lock:** The user's entire head, including facial features, ears, neck, and hairline/ponytail, must be frozen and pixel-preserved. - **Body Integrity:** The user's waist width and bust volume must not be altered to fit the model's slim silhouette. The user's shoulder width must be maintained. The reconstruction of the bare arms (necessitated by the sleeveless switch) must match the user's skin tone on the face and hands perfectly, without slimming the arm mass.