guide
scroll-spy
An IntersectionObserver-driven active-section tracker — renders as a nav list on desktop, a select on mobile. Updates the URL hash for shareable links.
Overview
Use the list to jump between sections.
Active section
IntersectionObserver tracks a narrow band near the top.
Shareable links
Navigation updates the URL hash.
Scroll the panel — the active item follows. On narrow screens, the list becomes a select.
Installation
Usage
ScrollSpy: Root · List · Select