declare const LAYOUT_OBSERVER: unique symbol;
declare const LAYOUT_OBSERVERS: unique symbol;
type Observer = [varName: string, fn: (val: string) => void];
declare global {
    interface Window {
        [LAYOUT_OBSERVER]?: MutationObserver;
        [LAYOUT_OBSERVERS]?: Set<Observer>;
    }
}
export type VarObserver = (val: number) => void;
export declare class CssVar {
    private name;
    private default;
    private observers;
    constructor(name: string, defaults: CSSStyleDeclaration);
    set: (to: number) => void;
    reset: () => void;
    get value(): number;
    observe: (fn: VarObserver) => () => void;
    private lastSeen?;
    private onChange;
}
/** Control the --layout-max-width css var. */
export declare const maxWidth: CssVar;
/** Control the --layout-header-base-height css var. */
export declare const headerHeight: CssVar;
/** Control the --layout-header-under-height css var. */
export declare const headerUnderHeight: CssVar;
/** Control the --layout-banner-height css var. */
export declare const bannerHeight: CssVar;
/** Control the --layout-sidebar-width css var. */
export declare const sidebarWidth: CssVar;
/** Control the --layout-toolbar-width css var. */
export declare const toolbarWidth: CssVar;
/** Control the --layout-panel-height css var. */
export declare const panelHeight: CssVar;
/** Control the --layout-cookie-height css var. */
export declare const cookieHeight: CssVar;
export {};