/**
 * Tracks container width / viewport and returns a small screen-size bag.
 * If a ref is passed, the hook observes that element via ResizeObserver
 * and reacts to its width changes; otherwise it tracks window width.
 */
export declare const useResponsive: (containerRef?: React.RefObject<HTMLElement>) => {
    isMobile: boolean;
    isTablet: boolean;
    isLaptop: boolean;
    isDesktop: boolean;
    screenSize: "sm" | "md" | "lg" | "xl";
    containerWidth: number;
};
