Side menu
A vertical nav primitive. Sections group, items expand, the current route lights with an accent rail. Collapse to icon-only when the page asks for breathing room; at narrow widths it tucks itself into a drawer trigger.
Selecting Galaxies shows the current-route rail and accent tint. Click the chevron groups to fold and unfold nested rows.
Compact mode keeps a 64px rail. Persisted to
localStorage so the choice survives reloads.Scroll this region — the menu rides the viewport once it reaches the top.
Resize this stage below 600px — the menu collapses to a drawer trigger via container query.