Nannoy/webgl-portfolio ? reverse-engineered prompt

Build me a single page immersive landing site called Kage, inspired by Kyoto temples and quiet night scenes.

I want it to feel cinematic and alive, with a full screen WebGL background, smooth scroll based chapter transitions, and a strong editorial layout that mixes English and Japanese text. The page should have a preload screen, a sticky nav that hides and shows while scrolling, a big hero section, a few story style content sections, some interactive cards, and a final call to action at the end.

Please keep it as one plain HTML file with vanilla JavaScript and CSS, not React or Next. Use Three.js for the 3D scene, and make the visual textures and effects generated in the browser if possible. It should work well on desktop and still feel good on mobile, with a simple fallback if WebGL is not available.

I also want it to be easy to customize the text and visuals later, so keep the content clearly separated and make the design feel polished, moody, and high end. If you need current docs or examples, look them up online.