/**
 * Returns the computed z-index of the nearest overlay layer (e.g. Dialog), or
 * `undefined` when rendered outside one. Portaled popup components use this to
 * set their own z-index one level higher so they appear above the overlay.
 *
 * @see {@link PopupLayerContext} for the full rationale.
 */
export declare const usePopupLayer: () => {
    layer: HTMLDivElement | undefined;
};
