Two causes of the visible gap under the bar on phone and desktop: the
bar lived inside the page's `space-y-6` column, whose child margin also
offsets a fixed box (24px), and its bottom offset was hand-derived. It
now teleports to <body> and uses `--bottom-nav-height`. Measured in a
headless run: bar bottom == nav top on 390px and 1280px viewports.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01ByAwHU4pRnyE58YocQvAas
BottomNav measures itself (ResizeObserver) and writes
`--bottom-nav-height` on <html>; index.css declares the 0px default. Any
element that must sit flush above the nav pins with
`bottom: var(--bottom-nav-height)` instead of re-deriving
`3.5rem + env(safe-area-inset-bottom)` and drifting when the device's
inset, border or font scaling differs from that guess. The restaurant
item page's add-to-cart bar is migrated to it.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01ByAwHU4pRnyE58YocQvAas