Three UX fixes on the /trade-in/v2 overlays (feedback):
1. TopNav stays interactive while a section overlay is open. The a11y
audit #2081 put inert on the whole content wrap (which contains
TopNav), so opening an overlay disabled the top tabs. Move inert off
the wrap onto <main>/<footer> only; the nav is inert just for the
full-screen LocationDrawer. Users can now switch sections directly
from an open overlay. role=dialog/aria-modal/Esc/focus-trap kept.
2. «← К ОЦЕНКЕ» made a clear filled primary button (solid accentDeep bg,
white text ≥4.9:1 AA, shadow, hover lift) instead of the weak ghost
pill. Uses existing accent tokens only.
3. Backdrop click closes the overlay. Add a transparent sibling layer
below the panel (z below it, starting under the nav so tabs stay
clickable); clicks in the margin close it. Clicks inside the panel /
on its buttons never reach it (sibling, not ancestor) so they don't
close. Esc + focus restore preserved.
