3D Model: Create A Photorealistic 3D Model Of A Perfect Cube Made Of Clear Crystal. The Cube Should Be Floating In A Dark, Empty Space, Balanced On One Of Its Bottom Corners. The Light Source Should Be Positioned In A Way That It Passes Through The Crystal, Refracting And Reflecting Into A Vibrant Spectrum Of Colors (like A Prism Effect). The Colors Should Be Visible Both Within The Cube And Cast As Subtle Reflections Onto The Surrounding Dark Space. Ensure The Details Of The Crystal Are Sharp And The Color Transitions Are Smooth And Mesmerizing. The Overall Mood Should Be Ethereal And Captivating.