Styles.swift

var headerLabel: (UILabel) -> () = { control in
  control.font = .systemFont(ofSize: 20)
  control.textColor = .red
}
var bodyLabel: (UILabel) -> () = { control in
  control.font = .systemFont(ofSize: 15)
  control.textColor = .darkGray
}
var loginTextField: (UITextField) -> () = { control in
  control.font = .systemFont(ofSize: 15)
  control.textColor = .darkGray
}