01 / The idea
A rail for long pages.
Proximity rail
Only the main sections. Add waves from the marker settings to see the space between them.
Fill the space between chapters with smaller marks.
Long pages are easy to lose your place in. This rail keeps the document's shape at the edge of the screen without taking up a column.
Choose a mode and marker style above. Then scroll, hover over the rail, or use one of its links.
02 / Orientation
See where you are.
Each mark belongs to a section. The current one grows darker and longer while the page moves underneath it.
The rail shows enough structure to orient you without repeating the whole outline.
03 / Proximity
Move closer.
Move toward the rail and the nearest marks expand. In chapter mode, their names appear too.
Touch users can use the visible marks. Keyboard users can focus each link and read its label.
05 / For everyone
Small marks, full rows.
The marks stay small, but each one fills its row, so the target is the full row height on a 44px track. Tab focuses each chapter. Enter opens it and moves focus to the section.
Reduced motion turns smooth scrolling off. Screen readers announce the current section.
06 / What's next
Pick the right amount of navigation.
Docs minimap maps every paragraph. Turn on Expanded for the full-height wave field. Chapters lists the main sections, and the waves setting fills the space between them when you want more detail. Indicator only shows reading progress.
Lines take waves; dots take an optional rounded container. Position moves the rail to either side of the viewport. This experiment will stay in Labs until I know when it works better than a normal table of contents.
07 / Install
Take it home.
The rail ships as one item. Hand it your chapters and pick a mode; the defaults match this page. Each chapter needs a matching section id on the page: unique ids, focusable sections with scroll margins, window scrolling only.
Keyboard, screen readers, and reduced motion come along.