flex-basis-function.scss

$gutter: 10px;

@function px-to-pc($target, $context: $max-width) {
  @return ($target / $context) * 100%;
}

@function per-line($items) {
  $g-pct: px-to-pc($gutter) * 2;
  $g-total: $items * $g-pct;
  @return (100% / $items) - $g-total;
}