The Great Z-Index Struggle: 3D vs. HTML

One of the biggest challenges in building 3D web apps is making the HTML UI play nicely with the 3D scene. ### Transparent Canvases The key is setting your Three.js canvas to be transparent and using absolute positioning for your HTML elements. ### Pointer Events Managing pointer events is also crucial. You need to make sure that clicking on a UI button doesn't accidentally trigger a camera move in your 3D scene.