export declare const getMaskStyle: (element: HTMLElement, container: HTMLElement) => {
    width?: undefined;
    height?: undefined;
    borderTopWidth?: undefined;
    borderLeftWidth?: undefined;
    borderBottomWidth?: undefined;
    borderRightWidth?: undefined;
} | {
    width: number;
    height: number;
    borderTopWidth: number;
    borderLeftWidth: number;
    borderBottomWidth: number;
    borderRightWidth: number;
};