import { PositionT } from './types';
export type ScrollTarget = HTMLElement | Window | Document;
export declare function isDocument(val: unknown): val is Document;
export declare function isHtmlElement(el: unknown): el is HTMLElement;
export declare function getOffsetElement(el: HTMLElement): Element | null;
export declare function getScroll(el: ScrollTarget): {
    scrollLeft: number;
    scrollTop: number;
};
export declare function getScrollParents(el: HTMLElement): HTMLElement[];
export declare function getRelativeBounding(e: DOMRect, c: DOMRect): {
    top: number;
    bottom: number;
    left: number;
    right: number;
    width: number;
    height: number;
    offsetLeft: number;
    offsetTop: number;
    offsetRight: number;
    offsetBottom: number;
};
export type RelativeRect = ReturnType<typeof getRelativeBounding>;
export declare function getElementSize(el: HTMLElement | Window): {
    width: number;
    height: number;
    offsetWidth: number;
    offsetHeight: number;
};
export declare function getElementBorder(el: HTMLElement, dir?: PositionT | PositionT[]): {
    left?: number;
    right?: number;
    top?: number;
    bottom?: number;
};
export declare function getCssVariable(key: string, el?: HTMLElement): string;
export declare function supportTouch(): boolean;
export declare function mergeClass(...classList: Array<string | any[] | undefined>): any[];
interface ScrollTopOptions {
    container?: ScrollTarget;
    duration?: number;
}
export declare function scrollTo(y: number, opts: ScrollTopOptions): Promise<unknown>;
export declare function isOverflown(element?: HTMLElement): boolean;
/**
 * 判断元素是否在视口内
 */
export declare function isInViewport(element?: Element): boolean;
/**
 * 判断是否为不可见标签
 */
export declare function isNonVisibleTag(element: Element): boolean;
/**
 * 判断元素是否在视觉上隐藏
 */
export declare function isElementHidden(element: HTMLElement): boolean;
export {};