Banner was fixed at top: 60px (just below the 60px-tall topbar) at
z-index 999 — same vertical band as the sidebar (top: 60px, z-index
100) and the apps-layout subnav, so it covered the top 36px of both
when dev mode was on.
Moved to top: 0, z-index 1001 (above the topbar). When the banner is
visible, body.has-dev-banner now also shifts every other fixed-
positioned chrome element down by the banner's 36px:
.topbar 0 → 36
.sidebar 60 → 96
.apps-layout 60 → 96
.mobile-drawer 60 → 96 (already had this override)
Body padding-top stays at 96px (banner + topbar) — content offset is
unchanged. Standard environment-banner placement (Stripe test-mode,
GitHub staff-mode) and makes "you're in dev mode" actually visible
above your nav.
Signed-off-by: librelad <librelad@digitalangels.vip>
fa751e6cff