The mobile nav drawer's backdrop (z-40) was being painted over by the Leaflet
map: `.leaflet-container` doesn't establish its own stacking context, so its
internal high z-indexes (panes ~200–700, zoom controls ~1000) competed with the
page and bled over the drawer overlay — the map stayed bright while the rest of
the page dimmed.
Add `isolation: isolate` (Tailwind `isolate`) to the map container so those
z-indexes stay contained and the map sits below page overlays (menus, modals,
dialogs) like any other content. Verified in the browser with the drawer open
over an activity-detail map.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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