Retro Circuit Arcade

Create a single-file HTML5 retro arcade score-attack game called Retro Circuit.

Hard constraints:
- Embedded HTML/CSS/JS only; no external assets, analytics, APIs, or network calls.
- Keyboard and touch controls must both work.
- Keep the loop short, readable, and replayable.

Creative direction:
- 80s arcade energy, scanline texture, neon accents, chunky UI, bright pickups, and clear danger colors.
- Do not fall back to a plain snake clone unless you add a strong twist.

Core gameplay:
- The player moves through an arena, collects targets, avoids hazards, chains combos, and survives speed ramps.
- Include score, best score, combo meter, speed/danger bar, short start instructions, game-over overlay, and restart.
- Add at least one risk/reward mechanic such as timed bonus targets, near-miss combo, shrinking safe zones, or temporary slow motion.

Quality gates:
- The score loop should be obvious within 10 seconds.
- Hazards must be readable at high speed.
- Restart should be instant so players try again.