diff --git a/.changeset/content-role-dialog-element.md b/.changeset/content-role-dialog-element.md
new file mode 100644
index 0000000..cd5ffd3
--- /dev/null
+++ b/.changeset/content-role-dialog-element.md
@@ -0,0 +1,7 @@
+---
+'@dunky.dev/react-dialog': minor
+---
+
+`Dialog.Content` now renders a `<div>` carrying the `dialog` (or `alertdialog`) role instead of the native `<dialog>` element. Consumers styling `dialog { ... }` should target the part directly (or its role), and a forwarded ref is now an `HTMLDivElement`; `...props` accept `ComponentProps<'div'>`.
+
+The dialog window is the initial focus target — focusable in script, out of the tab order — which needs `tabindex="-1"`, and HTML states that [the `tabindex` attribute must not be specified on `dialog` elements](https://html.spec.whatwg.org/multipage/interactive-elements.html#the-dialog-element). The native element would only pay off through `showModal()`, and this contract deliberately keeps modality, dismissal, and focus in the core machine rather than splitting authority with the browser's built-in behavior — so the element brought nothing but a conformance violation. Nothing about the exposed semantics changes: the same role, `aria-modal`, name, description, and focus behavior as before. UA `<dialog>` resets (`position: static`, `border: none`) are no longer needed in consumer styles.
diff --git a/packages/native/dialog/src/dialog.tsx b/packages/native/dialog/src/dialog.tsx
index 146a63a..d74dee5 100644
--- a/packages/native/dialog/src/dialog.tsx
+++ b/packages/native/dialog/src/dialog.tsx
@@ -48,10 +48,7 @@ export const Trigger: PartComponent<DialogTriggerProps, View> = forwardRef<
   DialogTriggerProps
 >((props, forwardedRef) => {
   const { api } = useDialogContext()
-  const merged = mergeProps(
-    props as Record<string, unknown>,
-    normalize(api.parts.trigger),
-  ) as PressableProps
+  const merged = mergeProps<DialogTriggerProps>(props, normalize(api.parts.trigger))
   return <Pressable {...merged} ref={forwardedRef} />
 })
 
@@ -111,10 +108,7 @@ export const Backdrop: PartComponent<DialogBackdropProps, View> = forwardRef<
   // Only a modal dialog dims the app behind — non-modal coexists with it.
   if (!machine.context.modal) return null
 
-  const merged = mergeProps(
-    props as Record<string, unknown>,
-    normalize(api.parts.backdrop),
-  ) as PressableProps
+  const merged = mergeProps<DialogBackdropProps>(props, normalize(api.parts.backdrop))
   return <Pressable {...merged} ref={forwardedRef} />
 })
 
@@ -129,13 +123,13 @@ export const Viewport: PartComponent<DialogViewportProps, View> = forwardRef<
   DialogViewportProps
 >((props, forwardedRef) => {
   const { api } = useDialogContext()
-  const merged = mergeProps(
+  const merged = mergeProps<DialogViewportProps>(
     // `box-none`: the viewport itself never takes a press, so a press on the
     // empty area around the window falls through to the Backdrop behind it —
     // that fall-through is this substrate's viewport-press-counts-as-outside.
-    { pointerEvents: 'box-none' as const, ...(props as Record<string, unknown>) },
+    { pointerEvents: 'box-none', ...props },
     normalize(api.parts.viewport),
-  ) as ViewProps
+  )
   return <View {...merged} ref={forwardedRef} />
 })
 
@@ -150,14 +144,14 @@ export const Content: PartComponent<DialogContentProps, View> = forwardRef<
   DialogContentProps
 >((props, forwardedRef) => {
   const { api, machine } = useDialogContext()
-  const merged = mergeProps(props as Record<string, unknown>, {
+  const merged = mergeProps<DialogContentProps>(props, {
     ...normalize(api.parts.content),
     // The host's modal containment for assistive tech (iOS): everything
     // outside this view stops existing for VoiceOver — the native
     // aria-modal. The normalize translation has no home for it because only
     // views, not attributes, carry it.
     accessibilityViewIsModal: machine.context.modal,
-  }) as ViewProps
+  })
   return <View {...merged} ref={forwardedRef} />
 })
 
@@ -176,10 +170,7 @@ export const Title: PartComponent<DialogTitleProps, Text> = forwardRef<Text, Dia
       return () => machine.send({ type: 'part.presence', part: 'title', present: false })
     }, [machine])
 
-    const merged = mergeProps(
-      props as Record<string, unknown>,
-      normalize(api.parts.title),
-    ) as TextProps
+    const merged = mergeProps<DialogTitleProps>(props, normalize(api.parts.title))
     return <Text {...merged} ref={forwardedRef} />
   },
 )
@@ -201,10 +192,7 @@ export const Description: PartComponent<DialogDescriptionProps, Text> = forwardR
     return () => machine.send({ type: 'part.presence', part: 'description', present: false })
   }, [machine])
 
-  const merged = mergeProps(
-    props as Record<string, unknown>,
-    normalize(api.parts.description),
-  ) as TextProps
+  const merged = mergeProps<DialogDescriptionProps>(props, normalize(api.parts.description))
   return <Text {...merged} ref={forwardedRef} />
 })
 
@@ -217,10 +205,7 @@ export interface DialogCloseProps extends PressableProps {}
 export const Close: PartComponent<DialogCloseProps, View> = forwardRef<View, DialogCloseProps>(
   (props, forwardedRef) => {
     const { api } = useDialogContext()
-    const merged = mergeProps(
-      props as Record<string, unknown>,
-      normalize(api.parts.close),
-    ) as PressableProps
+    const merged = mergeProps<DialogCloseProps>(props, normalize(api.parts.close))
     return <Pressable {...merged} ref={forwardedRef} />
   },
 )
diff --git a/packages/react/dialog/SPEC.md b/packages/react/dialog/SPEC.md
index a23d558..eaf2f99 100644
--- a/packages/react/dialog/SPEC.md
+++ b/packages/react/dialog/SPEC.md
@@ -44,11 +44,17 @@ React-specific notes on top of the core contract:
   background should be a non-scrolling positioned boundary wrapping an inner
   scroller — portal into the boundary; the overlay fills its visible box and
   the backdrop blocks the scroller behind it (see the `scoped` story).
-- **`Content`** renders the native `<dialog>` element, always with the `open`
-  attribute since it only mounts while the dialog is open. It is shown without
-  `showModal()` on purpose: modality, dismissal, and focus stay driven by the
-  core contract, consistent across browsers, instead of splitting authority
-  with the browser's built-in dialog behavior.
+- **`Content`** renders a `<div>` carrying the `dialog` (or `alertdialog`)
+  role, not the native `<dialog>` element. The dialog window is the initial
+  focus target — focusable in script, out of the tab order — which needs
+  `tabindex="-1"`, and HTML states that
+  [the `tabindex` attribute must not be specified on `dialog` elements](https://html.spec.whatwg.org/multipage/interactive-elements.html#the-dialog-element).
+  The native element would only pay off through `showModal()`, and this
+  contract deliberately keeps modality, dismissal, and focus with the core
+  machine rather than splitting authority with the browser's built-in behavior
+  (see the core spec's Internals). With the role explicit and the element
+  neutral, there is nothing left to gain and one conformance rule left to
+  break.
 - **`Backdrop`** renders nothing when the dialog is non-modal (`modal={false}`),
   per the core parts contract.
 - **Exit animation** (`animated`): style the exit on the parts'
@@ -130,12 +136,12 @@ The positioning + scroll layer around the dialog window.
 
 ### `Dialog.Content`
 
-The dialog window; renders the native `<dialog>`.
+The dialog window; renders a `<div>` with the `dialog` role.
 
 | Prop           | Type                             | Default           | Description                                 |
 | -------------- | -------------------------------- | ----------------- | ------------------------------------------- |
 | `initialFocus` | `RefObject<HTMLElement \| null>` | the dialog window | The element to focus when the dialog opens. |
-| `...props`     | `ComponentProps<'dialog'>`       | —                 | Forwarded to the rendered `<dialog>`.       |
+| `...props`     | `ComponentProps<'div'>`          | —                 | Forwarded to the rendered `<div>`.          |
 
 ### `Dialog.Title`
 
diff --git a/packages/react/dialog/src/dialog.tsx b/packages/react/dialog/src/dialog.tsx
index 7f1d39e..b37a89f 100644
--- a/packages/react/dialog/src/dialog.tsx
+++ b/packages/react/dialog/src/dialog.tsx
@@ -83,7 +83,10 @@ export const Trigger: PartComponent<DialogTriggerProps, HTMLButtonElement> = for
   DialogTriggerProps
 >((props, forwardedRef) => {
   const { api } = useDialogContext()
-  const merged = mergeProps({ type: 'button' as const, ...props }, normalize(api.parts.trigger))
+  const merged = mergeProps<DialogTriggerProps>(
+    { type: 'button', ...props },
+    normalize(api.parts.trigger),
+  )
   return <button {...merged} ref={forwardedRef} />
 })
 
@@ -128,7 +131,7 @@ export const Backdrop: PartComponent<DialogBackdropProps, HTMLDivElement> = forw
     onClick?: (event: MouseEvent<HTMLDivElement>) => void
   } & Record<string, unknown>
 
-  const merged = mergeProps(props as Record<string, unknown>, {
+  const merged = mergeProps<DialogBackdropProps>(props, {
     ...bindings,
     // Only the topmost dialog of a stack answers an outside press.
     onClick: (event: MouseEvent<HTMLDivElement>) => {
@@ -157,7 +160,7 @@ export const Viewport: PartComponent<DialogViewportProps, HTMLDivElement> = forw
     onClick?: (event: MouseEvent<HTMLDivElement>) => void
   } & Record<string, unknown>
 
-  const merged = mergeProps(props as Record<string, unknown>, {
+  const merged = mergeProps<DialogViewportProps>(props, {
     ...bindings,
     // Content presses bubble up here — only a press that started on the
     // viewport itself is an outside interaction, and only the topmost dialog
@@ -177,18 +180,18 @@ export const Viewport: PartComponent<DialogViewportProps, HTMLDivElement> = forw
 // close, traps while modal
 // =============================================================================
 
-export interface DialogContentProps extends ComponentPropsWithoutRef<'dialog'> {
+export interface DialogContentProps extends ComponentPropsWithoutRef<'div'> {
   /** The element to focus when the dialog opens. @default the dialog window */
   initialFocus?: RefObject<HTMLElement | null>
 }
 
-export const Content: PartComponent<DialogContentProps, HTMLDialogElement> = forwardRef<
-  HTMLDialogElement,
+export const Content: PartComponent<DialogContentProps, HTMLDivElement> = forwardRef<
+  HTMLDivElement,
   DialogContentProps
 >(({ initialFocus, ...props }, forwardedRef) => {
   const { api, machine, depth, container, backdropRef } = useDialogContext()
-  const contentRef = useRef<HTMLDialogElement>(null)
-  useImperativeHandle(forwardedRef, () => contentRef.current as HTMLDialogElement)
+  const contentRef = useRef<HTMLDivElement>(null)
+  useImperativeHandle(forwardedRef, () => contentRef.current as HTMLDivElement)
   const initialFocusRef = useRef(initialFocus)
   initialFocusRef.current = initialFocus
 
@@ -257,15 +260,13 @@ export const Content: PartComponent<DialogContentProps, HTMLDialogElement> = for
     last: () => document.getElementById(api.ids.close),
   })
 
-  const merged = mergeProps(props as Record<string, unknown>, {
-    ...normalize(api.parts.content),
-    // The native <dialog> is display:none without `open`; Content only mounts
-    // while the dialog occupies the tree (open or mid-exit), so the attribute
-    // is unconditionally true.
-    open: true,
-  })
+  // A neutral element with the role, not <dialog>: the window is the initial
+  // focus target, so it carries tabindex — which HTML forbids on <dialog> —
+  // and the native element only pays off via showModal(), which this contract
+  // deliberately doesn't use.
+  const merged = mergeProps<DialogContentProps>(props, normalize(api.parts.content))
 
-  return <dialog {...merged} ref={contentRef} />
+  return <div {...merged} ref={contentRef} />
 })
 
 // =============================================================================
@@ -285,7 +286,7 @@ export const Title: PartComponent<DialogTitleProps, HTMLHeadingElement> = forwar
     return () => machine.send({ type: 'part.presence', part: 'title', present: false })
   }, [machine])
 
-  const merged = mergeProps(props as Record<string, unknown>, normalize(api.parts.title))
+  const merged = mergeProps<DialogTitleProps>(props, normalize(api.parts.title))
   return <h2 {...merged} ref={forwardedRef} />
 })
 
@@ -306,7 +307,7 @@ export const Description: PartComponent<DialogDescriptionProps, HTMLDivElement>
     return () => machine.send({ type: 'part.presence', part: 'description', present: false })
   }, [machine])
 
-  const merged = mergeProps(props as Record<string, unknown>, normalize(api.parts.description))
+  const merged = mergeProps<DialogDescriptionProps>(props, normalize(api.parts.description))
   return <div {...merged} ref={forwardedRef} />
 })
 
@@ -321,7 +322,10 @@ export const Close: PartComponent<DialogCloseProps, HTMLButtonElement> = forward
   DialogCloseProps
 >((props, forwardedRef) => {
   const { api } = useDialogContext()
-  const merged = mergeProps({ type: 'button' as const, ...props }, normalize(api.parts.close))
+  const merged = mergeProps<DialogCloseProps>(
+    { type: 'button', ...props },
+    normalize(api.parts.close),
+  )
   return <button {...merged} ref={forwardedRef} />
 })
 
diff --git a/packages/react/dialog/stories/dialog.stories.tsx b/packages/react/dialog/stories/dialog.stories.tsx
index 14f8446..12c7dbb 100644
--- a/packages/react/dialog/stories/dialog.stories.tsx
+++ b/packages/react/dialog/stories/dialog.stories.tsx
@@ -25,9 +25,9 @@ const viewport: CSSProperties = {
   padding: 24,
 }
 const content: CSSProperties = {
-  // Reset the UA <dialog> styles so the viewport's flex centering owns position.
-  position: 'static',
-  border: 'none',
+  // `margin: auto` inside the viewport's flex box does the centering;
+  // `relative` makes the corner Close button pin to the window, not the page.
+  position: 'relative',
   margin: 'auto',
   maxWidth: 480,
   padding: 24,
diff --git a/packages/react/dialog/tests/dialog.test.tsx b/packages/react/dialog/tests/dialog.test.tsx
index d82dbe3..d2fd82a 100644
--- a/packages/react/dialog/tests/dialog.test.tsx
+++ b/packages/react/dialog/tests/dialog.test.tsx
@@ -258,11 +258,13 @@ describe('Dialog', () => {
       expect(trigger.getAttribute('aria-controls')).toBe(screen.getByRole('dialog').id)
     })
 
-    it('renders the native dialog element, marked open', () => {
+    // The window takes initial focus, so it carries tabindex — which HTML
+    // forbids on <dialog>. Hence a neutral element with an explicit role.
+    it('renders the dialog window as a scripted focus target outside the tab order', () => {
       render(<DefaultDialog defaultOpen />)
       const dialog = screen.getByRole('dialog')
-      expect(dialog.tagName).toBe('DIALOG')
-      expect(dialog.hasAttribute('open')).toBe(true)
+      expect(dialog.tagName).not.toBe('DIALOG')
+      expect(dialog.tabIndex).toBe(-1)
     })
 
     it('content is labelled by the Title and described by the Description', () => {