Cross-document view transitions are part of the CSS View Transitions Module Level 2 specification. They enable smooth navigation between pages on multi-page applications without any JavaScript framework — just a single CSS rule.
The browser handles the entire transition lifecycle: it captures a snapshot of the current page, navigates to the new page, captures a snapshot of the new page, and then morphs between the two snapshots on the compositor thread.
Cascade layers explained with real examples.
Responsive components without media queries.
Parent selection and more with :has().