/** Tailwind `md` breakpoint — below this we treat the layout as "mobile". */
export declare const MOBILE_BREAKPOINT_PX = 768;
/**
 * Reactive `max-width` media-query match. Call once inside a component:
 *
 * ```ts
 * const viewport = createIsMobile();
 * const isMobile = $derived(viewport.current);
 * ```
 */
export declare function createIsMobile(breakpointPx?: number): {
    readonly current: boolean;
};
export type ViewportCtx = {
    get isMobile(): boolean;
};
export declare function setViewport(ctx: ViewportCtx): ViewportCtx;
/** Reactive `isMobile`. Falls back to desktop (`false`) when used outside an
 * editor, so the overridable section components still render standalone. */
export declare function useViewport(): ViewportCtx;