highly detailed, ultra-realistic 3D model of a medieval-style green and yellow leather backpack with blue and orange accents. Include a zipper, multiple compartments, and adjustable straps. Ensure even lighting and a neutral background to capture intricate details. Highlight the shape, design, and color textures accurately, emphasizing the medieval theme. Textures in 4K for clarity and fine detail, positioning symmetrically with a direct, neutral camera angle., #ChristmasAdventure#,