Orthographic projection was chosen here deliberately - that's why elevation makes no difference to the size of the object but changes the shadow. Perspective projection won't work well with scrolling because the angle of the object would have to subtly change when the user scrolls. Orthographic projection doesn't need to handle that.

The docs have a page where the lighting and camera setup is explained with an actual threejs 3d scene - https://kikkupico.github.io/ambientcss/guide/concept/#how-it... . Hope it helps!

Regarding the textures, they respond to lighting but not especially well. In the demo app, you can scroll to the materials page and use the theme switcher at the top to see how the texture respond.