/**
 * Shared error handler for universal login routes (/u/ and /u2/).
 *
 * Renders a branded HTML error page instead of returning plain text or JSON.
 */
import { Context } from "hono";
import type { Bindings, Variables } from "../../types";
/**
 * Create an async onError handler that renders a branded error page.
 */
export declare function createUniversalLoginErrorHandler(): (err: Error, c: Context<{
    Bindings: Bindings;
    Variables: Variables;
}>) => Promise<Response>;
