export declare const onBackdropStylesChange: import("rxjs").Observable<void>;
export declare const usesBackdropLayout: () => import("@cssfn/css-types").CssRule;
export declare const usesBackdropVariants: () => import("@cssfn/css-types").CssRule;
export declare const usesBackdropStates: () => import("@cssfn/css-types").CssRule;
declare const _default: () => import("@cssfn/css-types").CssRule;
export default _default;