/**
 * @class ContrastAdjuster
 * @extends HTMLElement
 * @description A custom element that provides a clickable card to cycle through global
 * contrast settings. It applies a data attribute to the <html> element.
 * It reuses the <tone-card> design.
 */
export declare class ContrastAdjuster extends HTMLElement {
    private shadow;
    private currentModeIndex;
    private toneCard;
    private toneCardContent;
    constructor();
    connectedCallback(): void;
    disconnectedCallback(): void;
    private attachListeners;
    private removeListeners;
    private handleClick;
    private applyMode;
    private handleReset;
    private loadState;
    private saveState;
    private updateUI;
    private render;
}
