declare namespace Ext {
    export namespace dom {
        export interface LayerConfig {
            cls?: string;
            constrain?: boolean;
            dh?: object;
            hideMode?: string;
            shadow?: string | boolean;
            shadowOffset?: number;
            shim?: string | boolean;
            useDisplay?: boolean;
            visibilityCls?: string;
            zindex?: number;
        }

        export class Layer extends Ext.dom.Element  {
            public constructor(config?: object, existingEl?: string | HTMLElement);
        }
    }
}