Fix: bottom tab scrolls with the page on mobile (overflow-x hidden→clip)
body (and on mobile body+html) had overflow-x:hidden. hidden automatically sets
the other axis to overflow:auto → body becomes a scroll container → position:fixed
(the bottom tab) becomes relative to it and scrolls along (visible e.g. on the
admin list). overflow-x:clip clips horizontally without creating that scroll context;
hidden stays as fallback for iOS <16. CSS cache-buster v6.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@…>