export declare function isValidColor(color: any): any;
export declare function normalizeHex(hex: any): any;
export declare function relLuminancesContrast(relLuminanceLighter: any, relLuminanceDarker: any): number;
export declare function relLuminance(color: any): any;
export declare function contrast(foregroundColor: any, backgroundColor: any): number;
export declare function foreground(backgroundColor: any): "black" | "white";