export declare function isGif(url: string): boolean;
export declare const earthMoonImage: {
    url: string;
    width: number;
    height: number;
};
export declare const frescoImage: {
    url: string;
    width: number;
    height: number;
};
export declare const portraitImage: {
    url: string;
    width: number;
    height: number;
};
export declare const portraitImageTitle = "The Arnolfini Portrait";
export declare const portraitImageCaption = "Jan van Eyck, *The Arnolfini Portrait*, 1434, oil on oak panel, 82.2 x 60 cm (National Gallery, London; photo: [Steven Zucker](https://flic.kr/p/2qEGNDi), CC BY-NC-SA 4.0)";
export declare const portraitImageLongDescription = "Jan van Eyck, The Arnolfini Portrait, 1434, oil on oak panel, 82.2 x 60 cm (National Gallery, London; photo: Steven Zucker, CC BY-NC-SA 4.0)";
export declare const scienceImage: {
    url: string;
    width: number;
    height: number;
};
export declare const scienceImageCaption = "*A diagram of prophase. During this stage of mitosis, chromosomes condense, the nuclear envelope breaks apart, and the mitotic spindle begins to form. Created with [Biorender.com](BioRender.com).*";
export declare const scienceImageAlt = "A diagram shows a single, circular cell.";
export declare const graphieImage: {
    url: string;
    width: number;
    height: number;
};
export declare const graphieImageAlt = "An array of isosceles triangles. A triangle has height A. Two smaller triangle, one with height B and one with height C, have approximately the same combined height as A.";
export declare const gifImage: {
    url: string;
    width: number;
    height: number;
};
export declare const gifImageAlt = "A person on a skateboard moves back and forth across a concrete structure that forms the shape of a U.";