import React from "react";
import "./index.less";
export interface Props {
    /**
     * Pass 0 or negative will invalidate the time into --:--:--.
     */
    timeToComplete: number;
    onComplete?: () => void;
    /**
     * @param remainingSecond - positive ONLY, use `onComplete` for remaining second is 0
     */
    onTick?: (remainingSecond: number) => void;
    /**
     * @param hours/minutes/seconds - well-formatted in exact two chars
     * @param remainingSecond - NULL if not applicable
     */
    renderer?: (hours: string, minutes: string, seconds: string, remainingSecond: number | null) => React.ReactElement | string;
    isHidden?: boolean;
    className?: string;
    style?: React.CSSProperties;
}
export declare const Countdown: (props: Props) => React.JSX.Element | null;