@type t() :: %LINE.Bot.MessagingApi.Model.FlexBox{
action: LINE.Bot.Model.Action.t() | nil,
alignItems: String.t() | nil,
background: LINE.Bot.Model.FlexBoxBackground.t() | nil,
backgroundColor: String.t() | nil,
borderColor: String.t() | nil,
borderWidth: String.t() | nil,
contents: [LINE.Bot.Model.FlexComponent.t()],
cornerRadius: String.t() | nil,
flex: integer() | nil,
height: String.t() | nil,
justifyContent: String.t() | nil,
layout: String.t(),
margin: String.t() | nil,
maxHeight: String.t() | nil,
maxWidth: String.t() | nil,
offsetBottom: String.t() | nil,
offsetEnd: String.t() | nil,
offsetStart: String.t() | nil,
offsetTop: String.t() | nil,
paddingAll: String.t() | nil,
paddingBottom: String.t() | nil,
paddingEnd: String.t() | nil,
paddingStart: String.t() | nil,
paddingTop: String.t() | nil,
position: String.t() | nil,
spacing: String.t() | nil,
type: String.t(),
width: String.t() | nil
}