App Shell
The sidebar sits directly on the app background, with small neutral icon tiles and a quiet nested guide rail. A subtle gray row identifies the selected destination; workspace and account controls anchor the header and footer.
Floating shell
Interactive navigation with rounded icon tiles. Select a page, expand a section, or collapse the sidebar with the toggle or Cmd+B.
Full-bleed (carded={false})
Surfaces that compose their own floating panels (e.g. chat) opt out of the page card and own the full inset.