type Styles = ViewportStyles | ((s: ViewportStyles) => ViewportStyles) | null; interface Viewport { name: string; styles: Styles; type: 'desktop' | 'mobile' | 'tablet' | 'other'; } interface ViewportStyles { height: string; width: string; } interface ViewportMap { [key: string]: Viewport; } export { Styles as S, ViewportMap as V, Viewport as a, ViewportStyles as b };