export interface WindowSize {
    innerHeight: number;
    innerWidth: number;
    outerHeight: number;
    outerWidth: number;
}
/**
 * Hook that returns current window dimensions.
 *
 * Note: it might return null on first render,
 * when `window` object is not defined (for server side rendering, for example).
 */
export declare function useWindowSize(): WindowSize | null;