CLASSIC ARCADE BENCHMARK 08: Bumper Rush. Build a complete playable browser arcade game as one self-contained index.html using Three.js. Create an original bumper-car-inspired vehicle arena score attack. The player steers a small vehicle, collides with at least two readable rival behaviours, scores through deliberate impacts, builds a combo, sees a fail/end state, and restarts instantly. Include clear arena boundaries and at least three impact-relevant features such as score walls, boost strips, bumpers, slow zones, charge pads, breakable barriers, or hazard gates. Productive collisions must visibly differ from unproductive bumps. Add a limited tactical tool such as dash, brake-turn, shield, magnetic bumper, or rebound marker, and announced arena pulse phases that open high-value but risky routes. Escalate through arena geometry, rival behaviour, and route choices, not uncontrolled collision chaos. Support keyboard and touch controls plus score/local high score. Theme, vehicles, arena setting, palette, story, and audio are open. No external asset pack. Submit final index.html only, not a mockup or explanation, with no build step.