Auto-detect low-end devices (< 4 cores or touch) and reduce visual complexity: 60% fewer particles, 6 vs 16 speed lines, 15 vs 40 stars, halved datacenter buildings/racks, skip LED blinking animations, fewer GPU graveyard chips, reduced afterimages and exhaust particles. Toggle in fight viewer (LO/HI button), persisted in localStorage. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>