@function u($multiplier) {
  $baseline-number: 6;

  @if $responsive == true {
    @return 16 / ($multiplier * $baseline-number) + rem
  }

  @return $multiplier * $baseline-number + px
}

// function based on the vertical rhythm, used to calculate all proportions without visual clutter

//
// e.g. padding: u(1) u(2) u(3) u(1);

@function u($multiplier) {
  $baseline-number: 6;

  @if $responsive == true {
    @return ($multiplier * $baseline-number) / 16 + rem
  }

  @return $multiplier * $baseline-number + px
}

Add comments to new function
Add comments to new function
