/**
 * Returns an ease-out CSS animation string with a slightly steeper curve
 * than usual.
 *
 * @param duration Duration in milliseconds
 * @param delay Delay in milliseconds
 */
export declare function getEaseOutSteep(duration: number, delay?: number): string;
/**
 * Returns an ease-out-back CSS animation string with a slightly steeper
 * curve than usual.
 *
 * @param duration Duration in milliseconds
 * @param delay Delay in milliseconds
 */
export declare function getEaseOutSteepBack(duration: number, delay?: number): string;
/**
 * Returns a linear CSS animation string
 *
 * @param duration Duration in milliseconds
 * @param delay Delay in milliseconds
 */
export declare function getEaseLinear(duration: number, delay?: number): string;