Weekend tint: hsl(0 0% 6%) was lighter than page bg #0a0a0a (imperceptible).
Changed to hsl(0 0% 2%) = #050505 for visible darkening. Added rule for
fc-daygrid-day-frame to paint above FC6 internal layers.
Dot spacing: Reduced padding from 1px 4px to 1px 2px for tighter edge gap.
FOUC fix: Moved umbra-event class from eventDidMount (post-paint) to
eventClassNames (synchronous pre-mount). eventDidMount now only sets
the --event-color CSS custom property.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>