import { Padding } from './types';
/**
 * Returns a React 19 **callback ref** that keeps a Radix floating panel fully
 * visible within the viewport by applying a CSS `translate` correction.
 *
 * A callback ref is required because Radix `Portal` mounts content in a second
 * render pass, so a parent `useLayoutEffect` would fire while the node is still
 * `null`; the callback fires exactly when the DOM node attaches.
 *
 * @param collisionPadding - Minimum gap in px between the panel and each
 *   viewport edge. Accepts a uniform number or a per-side object. @default 8
 */
export declare const useViewportShift: (collisionPadding?: Padding) => (content: HTMLDivElement | null) => (() => void) | void;