Header NavLinks (Top Stories/Canada/National/All) always rendered and
overflowed the ~360-400px viewport, causing whole-page horizontal
scroll + wrapped/bleeding active pill. Now hidden on phones (the
horizontally-scrolling SectionPills row under the header remains the
mobile nav); inline nav returns at md (768px). Added overflow-x:clip on
html as a global NOOP-safe against any future sideways overflow.