# One-Shot Prompt

**Theme**: Neon arcade serpent lab
**Generated**: 2026-04-24

## Prompt

Create a polished single-file HTML5 Canvas Snake game with distinctive design, keyboard and touch controls, scoring, difficulty, and crisp mobile support.

Build it as a self-contained static `index.html` file. Render the game on an HTML5 `<canvas>` using no external images and no server-side code. Theme the game as a neon arcade serpent lab called **Lumen Coil**: a dark indigo playfield with a subtle animated grid, cyan and magenta glow trails, a segmented luminous snake with a distinct eyed head, and pulsing energy-orb food. Use a tight palette of near-black, cyan, magenta, violet, and warm amber.

Required gameplay: continuous snake movement; Arrow and WASD controls; swipe controls on touch screens; food grows the snake by one segment; walls and self-collisions end the run; score, high score, level, and difficulty are visible; high score persists with `localStorage`; speed ramps as score increases with a sensible cap; input buffering prevents missed turns; 180-degree reversals are blocked.

Required states: animated start screen with title, controls, and difficulty buttons; playing state; paused state with P or Escape; game-over state with final score, high score, and restart prompt. Tapping or pressing Space should start and restart. The UI should be responsive, readable on phones, and support touch-friendly controls.

Required polish: smooth `requestAnimationFrame` loop with fixed-step updates and interpolation; retina-sharp canvas sizing using `devicePixelRatio`; subtle background star/noise particles; animated food pulse; collection particles; a short screen flash/shake on game over; CSS overlay transitions; reduced-motion support; inline SVG favicon; no console errors; all CSS and JavaScript embedded in the file.

## Notes

- The finished route is a single self-contained HTML file intended for `/snake/` in the catalog.
- It uses Canvas for all game rendering, CSS only for layout and overlays, and browser storage for high score persistence.