Nested and morph

<Sheet.Root>
  <Sheet.Trigger>Open</Sheet.Trigger>
  <Sheet.Content className="sheet">
    {/* a Sheet.Root rendered in here just works */}
    <Sheet.Root>
      <Sheet.Trigger>Open child</Sheet.Trigger>
      <Sheet.Content className="sheet">Child sheet</Sheet.Content>
    </Sheet.Root>
  </Sheet.Content>
</Sheet.Root>

Nesting is automatic: a Sheet.Root rendered inside another sheet’s content registers with the parent, which recedes and dims while the child is open. Height morphs the same way: the sheet springs to fit new content whenever it changes inside an open sheet. For a cross-fade between views instead of a resize, wrap the state update in document.startViewTransition (feature-detected, falls back to an instant swap).

Page transitionsMark your page wrapper data-scrollsheet-background and backgroundEffect scales, insets, and rounds it in sync with the sheet's travel, iOS-style.