import type { DefaultTheme } from 'styled-components';
/**
 * A contextual styled-components DefaultTheme object with default key-value pairs for CSS props.
 */
export declare const DEFAULT_THEME: DefaultTheme;
/**
 * If theme param is a valid object, attempt to merge with static DEFAULT_THEME.
 * A new object of DefaultTheme type is returned, with properties overriden as defined in theme param.
 */
export declare const mergeThemes: (theme?: import("../types").PartialDeep<DefaultTheme> | undefined) => DefaultTheme;