Drops document-level View Transitions and the lesson hold: they dropped clicks for 120-180 ms, froze the screen
while route code loaded, and let the dock act on a stale lesson. Navigation now swaps immediately; only the
content region enters (opacity and a 6 px rise, 160 ms); a 2 px loading line appears when code or data takes over
150 ms; the dock works from the outline and the URL, so a second Next advances again; focus moves to the new h1
and a polite live region announces it. Route chunks of a feature preload together so the sidebar never drops.
Scroll restore stops on user input; pdf.js never starts a load after cleanup.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Router updates now run in a React transition, so a route whose code is still loading keeps the current page up
and the view transition captures the new page with its sidebar (it used to drop out and pop back on the first
course-to-lesson visit). The root group's 250 ms UA morph is off: pointer input goes to the document while a
transition runs, so it stays as short as the old page's 120 ms fade. The pointer-events rule had no effect.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Also turns off the fold height transition, which the universal selector does not reach (::details-content).
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Landscape images (imported video frames, slide pages) would lose most of the
picture in a 3:4 crop, so the tile keeps its monogram; portrait and
near-square images (w/h <= 1.05) fade in over it, cropped from the centre.
The header nav follows the mockup's segmented-control style: muted text, no
underline, the current area raised in accent.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
