/**
 * Run `start` now when the page is visible, otherwise on the next return to
 * it. Returns a cleanup that cancels a start that has not happened yet.
 */
export declare function whenPageVisible(start: () => void): () => void;
/**
 * Confetti for winning credits: two cannons from the lower corners and a pop
 * above the card. It is decorative (hidden from assistive technology), never
 * blocks a click, plays once per mount (change `key` to play it again), and
 * does nothing under reduced motion. Pieces animate transform and opacity
 * only, through the Web Animations API, so no global keyframes ship in the
 * app stylesheet. Each flight is sampled from a ballistic arc with drag.
 */
export declare function CelebrationBurst(): import("react").JSX.Element;