export declare class PlainScrollbar extends HTMLElement {
    private widget;
    constructor();
    connectedCallback(): void;
    disconnectedCallback(): void;
    get thumbSize(): number;
    set thumbSize(v: number);
    get value(): number;
    set value(v: number);
    get orientation(): string;
    set orientation(s: string);
    get orientationBoolean(): boolean;
    static get observedAttributes(): string[];
    attributeChangedCallback(attrName: string, _oldValue: string | null, newValue: string | null): void;
}