import { Observable } from 'rxjs';
export declare const getAttributeValueFromString: (string: string, key: string) => number;
export declare const injectCSSToFrame: (frameElement: HTMLIFrameElement, id: string, style: string, prepend?: boolean) => void;
export declare const removeCSS: (frameElement: HTMLIFrameElement, id: string) => void;
export declare const upsertCSSToFrame: (frameElement: HTMLIFrameElement | undefined, id: string, style: string, prepend?: boolean) => void;
export declare const getFrameViewportInfo: (frame: HTMLIFrameElement | undefined) => {
    hasViewport: boolean;
    widthToken: string | undefined;
    heightToken: string | undefined;
    width: number;
    height: number;
} | {
    hasViewport: boolean;
    widthToken: string | undefined;
    heightToken: string | undefined;
    width?: undefined;
    height?: undefined;
} | {
    hasViewport: boolean;
    widthToken?: undefined;
    heightToken?: undefined;
    width?: undefined;
    height?: undefined;
};
export declare const waitForFrameLoad: (stream: Observable<HTMLIFrameElement>) => Observable<HTMLIFrameElement>;
export declare const waitForFrameReady: (stream: Observable<HTMLIFrameElement>) => Observable<HTMLIFrameElement>;