/**
 * Returns the contrasting dark or light color based on the passed hex color
 *
 * http://24ways.org/2010/calculating-color-contrast/
 *
 * @param hex {string}
 * @param [darkColor] {string}
 * @param [lightColor]
 * @returns {string}
 */
export declare function getColorContrast(hex?: string | undefined, { darkColor, lightColor }?: {
    darkColor?: string | undefined;
    lightColor?: string | undefined;
}): string;
