sp-codes.de/bower_components/foundation-sites/scss/grid/_row.scss

// Foundation for Sites by ZURB
// foundation.zurb.com
// Licensed under MIT Open Source

////
/// @group grid
////

/// Change the behavior of columns defined inside this mixin to use a different column count.
/// @content
///
/// @param {Number} $columns - Number of columns to use.
/// @param {Boolean} $root [false]
///   If `false`, selectors inside this mixin will nest inside the parent selector.
///   If `true`, selectors will not nest.
@mixin grid-context(
  $columns,
  $root: false
) {
  // Store the current column count so it can be re-set later
  $old-grid-column-count: $grid-column-count;
  $grid-column-count: $columns !global;

  @if $root {
    @at-root { @content; }
  }
  @else {
    @content;
  }

  // Restore the old column count
  $grid-column-count: $old-grid-column-count;
}

/// Creates a grid row.
/// @content
///
/// @param {Number} $columns [null] - Column count for this row. `null` will use the default column count.
/// @param {Keywords} $behavior [null]
///   Modifications to the default grid styles. `nest` indicates the row will be placed inside another row. `collapse` indicates that the columns inside this row will not have padding. `nest collapse` combines both behaviors.
/// @param {Number} $width [$grid-row-width] - Maximum width of the row.
/// @param {Boolean} $cf [true] - Whether or not to include a clearfix.
/// @param {Number} $gutter [$grid-column-gutter] - Gutter to use when inverting margins, in case the row is nested.
@mixin grid-row(
  $columns: null,
  $behavior: null,
  $width: $grid-row-width,
  $cf: true,
  $gutter: $grid-column-gutter
) {
  $margin: auto;

  @if index($behavior, nest) != null {
    @include grid-row-nest($gutter);

    @if index($behavior, collapse) != null {
      margin-left: 0;
      margin-right: 0;
    }
  }
  @else {
    max-width: $width;
    margin-left: auto;
    margin-right: auto;
  }

  @if $cf {
    @include clearfix;
  }

  @if $columns != null {
    @include grid-context($columns) {
      @content;
    }
  }
}

/// Inverts the margins of a row to nest it inside of a column.
///
/// @param {Map|null} $gutter [null] - Gutter value to use when inverting the margins. Set to `null` to refer to the responsive gutter settings.
@mixin grid-row-nest($gutter: $grid-column-gutter) {
  @if type-of($gutter) == 'number' {
    $gutter: ($-zf-zero-breakpoint: $gutter);
  }
  max-width: none;

  @each $breakpoint, $value in $gutter {
    $margin: rem-calc($value) / 2 * -1;

    @include breakpoint($breakpoint) {
      margin-left: $margin;
      margin-right: $margin;
    }
  }
}