Scène isométrique de relations spatiales

Create a clear isometric illustration that makes the spatial relationships in the user request easy to inspect. Use a transparent cube as the central reference volume and arrange only the specified colored geometric solids around it. Respect the requested inside, outside, above, below, front, and back relationships, using visible cube edges to establish orientation. Keep the camera fixed in a three-quarter view with parallel edges rather than dramatic perspective. Make the glass lightly tinted and transparent enough to reveal enclosed shapes. Where an object passes across the cube, use consistent overlaps to explain its depth without hiding other required objects. Separate colors and silhouettes with soft, even illumination on a plain background. Include no labels, axes, measurements, or extra decorations. Return one still illustration, with every requested object visible. User request: Draw an isometric transparent cube with a red sphere inside upper back left, blue sphere inside lower front right, a green sphere outside above it, and a yellow cylinder crossing lower-left to upper-right.