# FullscreenMode reference

How fullscreen is presented: the browser Fullscreen API, a full-viewport overlay, or layout only while the parent presents it.

- `'controlled'`: layout-only; the parent decides how to present fullscreen.
- `'native'`: the browser Fullscreen API on the viewer root, falling back to `'overlay'`.
- `'overlay'`: a fixed, full-viewport layer with a focus trap; `Esc` closes it.

## Used by

- [Fullscreen](https://react-pdf-viewer-chi.vercel.app/react-pdf-viewer/fullscreen.md)

## Import

```ts
import type { FullscreenMode } from '@kingtech/react-pdf-viewer';
```

Signature: `type FullscreenMode = 'controlled' | 'native' | 'overlay'`

## Properties

| Name | Type | Default | Required | Description |
| --- | --- | --- | --- | --- |
| `controlled` | `'controlled'` | — | No | Layout only: the parent decides how to present fullscreen. |
| `native` | `'native'` | — | No | The browser Fullscreen API on the viewer root, falling back to `'overlay'`. |
| `overlay` | `'overlay'` | — | No | A fixed, full-viewport layer with a focus trap and scroll lock; `Esc` closes it. |

## Source

[packages/react-pdf-viewer/src/types.ts](https://github.com/kiralygyula92/react-pdf-viewer/blob/main/packages/react-pdf-viewer/src/types.ts#L35)