import { NgxScrollTopMode } from './ngx-scrolltop.interface';
import * as i0 from "@angular/core";
export declare class NgxScrollTopCoreService {
    private scrolledFromTop;
    private scrollOffset;
    private readonly isBrowser;
    private alreadyActivated;
    private document;
    onWindowScroll(mode: NgxScrollTopMode): boolean;
    private classicMode;
    private smartMode;
    scrollToTop(): void;
    static ɵfac: i0.ɵɵFactoryDeclaration<NgxScrollTopCoreService, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<NgxScrollTopCoreService>;
}