$utilities: map-merge(
  $utilities,
  (
    "flex": (
      property: flex,
      class: flex,
      variants: flex,
      values: (
        "1": 1 1 0%,
        "auto": 1 1 auto,
        "initial": 0 1 auto,
        "none": none,
      ),
    ),
  )
);