Elastic Tab Rail

A tab system with measured label widths, a springing active rail and contextual counters that remains fully keyboard operable.

• Product navigation
• Account flows
• Application shells

• Native tab roles and arrow-key behavior are preserved
• Active rail measures the selected label rather than guessing
• Counters remain visible without entering the accessible name
• A component-specific renderer and control contract—not a palette swap of another release
• Semantic controls, visible focus and keyboard navigation ship with the visual system

No animation package or external preview asset is required. Layout is container-scoped and decorative motion is disabled when reduced motion is requested.

Pointer, touch, horizontal trackpad and keyboard states use the same underlying component state.

Native landmarks and controls preserve reading order, visible focus and keyboard access. Motion never carries the only meaning.