export interface FullscreenControllerOptions {
	/** The root element to place into fullscreen. */
	element: HTMLElement;
	/** Whether fullscreen is enabled for this viewer. */
	enabled: boolean;
	/**
	* CSS class toggled on `element` as a faux-fullscreen fallback
	* when the Fullscreen API is unavailable (iOS Safari).
	*/
	fauxClassName?: string;
	/** Called on native `fullscreenchange` for the element. */
	onChange?: (isFullscreen: boolean) => void;
	/** Abort signal used to tear down the fullscreenchange listener. */
	signal?: AbortSignal;
}
/**
* Fullscreen API wrapper (#14). Handles native
* `requestFullscreen` / `exitFullscreen` and a CSS-class
* faux-fullscreen for engines that refuse real fullscreen
* (iOS Safari).
*/
export declare class FullscreenController {
	private readonly element;
	private readonly enabled;
	private readonly fauxClassName;
	private readonly onChange;
	constructor(options: FullscreenControllerOptions);
	/** Is the element currently in fullscreen (real or faux)? */
	isFullscreen(): boolean;
	/**
	* Enter fullscreen. Prefers native requestFullscreen, falls back
	* to a CSS faux-fullscreen class. No-op when disabled.
	*/
	enter(): Promise<void>;
	/** Exit fullscreen (real or faux). */
	exit(): Promise<void>;
	/** Toggle between windowed and fullscreen. */
	toggle(): Promise<void>;
}