hand-drawn 2D explainer cartoon illustration, thick clean black outlines, simplified readable forms, flat cel-style colors, soft minimal shading, expressive human characters, clean educational YouTube illustration, simple depth, clear focal hierarchy, no photorealism, no 3D rendering. Full-frame 16:9 2D cartoon illustration of the fully drained Naica crystal chamber. Forest of colossal translucent white selenite crystal beams crisscrossing wall-to-wall across dark limestone cave floor and walls. Soft glowing crystal highlights, clean bold black outlines, flat cel colors, no photorealism, no 3D, no text.
