3D solar system · qwen3.5-plus-02-15

The user wants me to create a single-page web app with a 3D solar system using Three.js. I need to:

1. Create an index.html file with:
   - CSS in a <style> tag
   - JS in a <script> tag
   - Include three.min.js from the current directory
   - Build a solar system with:
     - Sun at the center
     - Planets orbiting at varied speeds and sizes
     - Orbit-drag camera controls (I'll implement this manually since we can't use external OrbitControls)
     - Starfield background

Let me create this self-contained HTML file.

Done! I've created a complete 3D solar system web app in a single self-contained `index.html` file.

Features:
- **Sun** with glowing effect at the center
- **8 planets** (Mercury through Neptune) with:
  - Varied sizes (Mercury smallest at 2, Jupiter largest at 12)
  - Different orbital distances
  - Different orbital speeds (inner planets orbit faster)
  - Unique colors
  - Saturn has rings
- **Orbit lines** showing each planet's path
- **Starfield** with 10,000 stars in the background
- **Orbit-drag camera controls**:
  - Drag to rotate around the solar system
  - Scroll to zoom in/out
  - Shift + Drag to pan
  - Touch support for mobile
- **Info panel** showing controls
- All CSS and JavaScript inline, no external dependencies except the local `three.min.js`