User reported: 'header menu มีบรรทัดเกิน แปลกๆ' — the 'หน้าแรก'
active link had 2 horizontal lines under it (coral ::after + gray border-bottom).
ROOT CAUSE: v7-5 .fx-nav-menu>li had border-bottom: 1px solid meant
for MOBILE menu (separating stacked items) but the rule escaped
the @media block during Phase 6.2 refactor and now applied to
ALL viewports.
FIX: Add .fx-nav-menu>li { border-bottom: none; } in base CSS
(placed AFTER the original v7-5 rule so cascade applies it).
Mobile @media block below still re-enables border-bottom:1px
for stacked menu.
Verified in built CSS: 12 .fx-nav-menu rules, override present
and last. Build: 22 pages, 2.06s.
73d820412a