export declare const cssClassNames: {
    loaded: string;
    loading: string;
    failed: string;
};
export declare function removeCssClassName(element: HTMLImageElement | HTMLDivElement, cssClassName: string): void;
export declare function addCssClassName(element: HTMLImageElement | HTMLDivElement, cssClassName: string): void;
export declare function hasCssClassName(element: HTMLImageElement | HTMLDivElement, cssClassName: string): boolean;