Server states & outcomes
One component for every full-screen state: HTTP errors (4xx/5xx), warnings, success and failure. Each opens as a standalone page or inside the app frame. Unknown URLs under /new-design render the 404 for real; runtime errors render the 500.
Errors
Client (4xx) and server (5xx) failures.
Warnings
Recoverable states that need attention.
Success
Confirmation after a completed action.
Failure
An action that didn't complete.
Try a real 404: /new-design/this-page-does-not-exist