With-aside layout

This page sets pageLayout: with-aside. The PageSidebar override renders Starlight’s default table of contents exactly as usual, then adds an extra callout panel underneath it — look at the right-hand column on a wide viewport.

An additive override

Unlike the full-width and minimal layouts, which each remove something from the default page, this one only adds to it. The override always renders <Default /> for PageSidebar and layers extra markup around it, rather than branching between two different structures.

Why that distinction matters

Additive overrides are lower-risk to introduce on an existing site: since the default output is always rendered first, you can’t accidentally break the table of contents while building the extra panel — worst case, the added markup is wrong, not the whole right column.

A place for anything page-specific

The callout in the sidebar is static in this demo, but because it’s an ordinary Astro component (AsideCallout.astro) receiving props, it could just as easily read page frontmatter to show a call-to-action, a related- links list, or a feedback prompt that varies per page.