@function row-gutter($row-gutter) {
  $value: map-get($steller-row-gutters, '#{$row-gutter}');

  @if $value == null {
    @error 'row-gutter(#{$row-gutter}) function returned null value. Make sure the value is in $steller-row-gutters.';
  }

  @return $value;
}