 struct ModeDetails: Codable {
   private enum CodingKeys: String, CodingKey {
     case title
+    case subtitle
     case websiteURL = "URL"
     case rgbColor = "color"
     case required

  }
  
  let title: String
  let websiteURL: URL?
  let rgbColor: API.RGBColor
  let required: Bool?

  public func title(forModeIdentifier mode: String) -> String? {
    return response?.modes?[mode]?.title
  }

  /// - Parameter mode: The mode identifier for which you want the title
  /// - Returns: The localized subtitle as defined by the server
  @objc
  public func subtitle(forModeIdentifier mode: String) -> String? {
    return response?.modes?[mode]?.subtitle
  }

  /// - Parameter mode: The mode identifier for which you want the official website URL
  /// - Returns: The URL as defined by the server
  @objc
