/// Takes a given number and returns the factorial of that number.
///
/// @param {Number} $value - Any given number.
///
/// @return {Number} The factorial of $value.
///
/// @access public
/// @group Utilities
@function factorial($value) {
  $result: 1;

  @if $value == 0 {
    @return $result;
  }

  @for $index from 1 through $value {
    $result: $result * $index;
  }

  @return $result;
}