export default plugin;
interface IOptions {
    /** A multimatch pattern of files to run on. */
    pattern: string;
    /** The name of the css file in the metalsmith data. */
    cssFile: string;
    /**
     * The path under which the css is included in the template.
     * Important for knowing which <link> tag to replace.
     */
    cssPublicPath: string;
}
/**
 * Metalsmith plugin to inline critical css, and load the rest asynchronously.
 */
declare function plugin({ pattern, cssFile, cssPublicPath }: IOptions): (files: Record<string, any>, metalsmith: any, done: () => void) => void;