PF2e uses action-based spell sustaining, not damage-triggered
concentration checks. The Brain icon, purple border accent, and
damage pulse animation are now hidden when PF2e is active, and
the freed gutter column is reclaimed for row content. Concentration
state is preserved so switching back to D&D restores it.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>