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

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

////
/// @group flex-grid
////

/// Creates a container for a flex grid row.
///
/// @param {Keyword|List} $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 {Number} $columns [null] - Number of columns to use for this row. If set to `null` (the default), the global column count will be used.
/// @param {Boolean} $base [true] - Set to `false` to prevent basic styles from being output. Useful if you're calling this mixin on the same element twice, as it prevents duplicate CSS output.
/// @param {Number} $gutter [$grid-column-gutter] - Gutter to use when inverting margins, in case the row is nested.
@mixin flex-grid-row(
  $behavior: null,
  $width: $grid-row-width,
  $columns: null,
  $base: 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 $base {
    display: flex;
    flex-flow: row wrap;
  }

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

/// Calculates the `flex` property for a flex grid column. It accepts all of the same values as the basic `grid-column()` function, along with two extras:
///   - `null` (the default) will make the column expand to fill space.
///   - `shrink` will make the column contract, so it only takes up the horizontal space it needs.
///
/// @param {Mixed} $columns [null] - Width of the column.
@function flex-grid-column($columns: null) {
  // scss-lint:disable ZeroUnit
  $flex: 1 1 0px;

  @if $columns == shrink {
    $flex: 0 0 auto;
  }
  @else if $columns != null {
    $flex: 0 0 grid-column($columns);
  }

  @return $flex;
}

/// Creates a column for a flex grid. By default, the column will stretch to the full width of its container, but this can be overridden with sizing classes, or by using the `unstack` class on the parent flex row.
///
/// @param {Mixed} $columns [null] - Width of the column. Refer to the `flex-grid-column()` function to see possible values.
/// @param {Number} $gutter [$grid-column-gutter] - Space between columns, added as a left and right padding.
@mixin flex-grid-column(
  $columns: null,
  $gutter: $grid-column-gutter
) {
  // Base properties
  flex: flex-grid-column($columns);

  // Gutters
  @if type-of($gutter) == 'map' {
    @each $breakpoint, $value in $gutter {
      $padding: rem-calc($value) / 2;

      @include breakpoint($breakpoint) {
        padding-left: $padding;
        padding-right: $padding;
      }
    }
  }
  @else if type-of($gutter) == 'number' and strip-unit($gutter) > 0 {
    $padding: rem-calc($gutter) / 2;
    padding-left: $padding;
    padding-right: $padding;
  }

  // fixes recent Chrome version not limiting child width
  // https://stackoverflow.com/questions/34934586/white-space-nowrap-and-flexbox-did-not-work-in-chrome
  @if $columns == null {
    min-width: initial;
  }
  // max-width fixes IE 10/11 not respecting the flex-basis property
  @if $columns != null and $columns != shrink {
    max-width: grid-column($columns);
  }
}

/// Creates a block grid for a flex grid row.
///
/// @param {Number} $n - Number of columns to display on each row.
/// @param {String} $selector - Selector to use to target columns within the row.
@mixin flex-grid-layout(
  $n,
  $selector: '.column'
) {
  flex-wrap: wrap;

  > #{$selector} {
    $pct: percentage(1/$n);

    flex: 0 0 $pct;
    max-width: $pct;
  }
}

/// Changes the source order of a flex grid column. Columns with lower numbers appear first in the layout.
/// @param {Number} $order [0] - Order number to apply.
@mixin flex-grid-order($order: 0) {
  @warn 'This mixin is being replaced by flex-order(). flex-grid-order() will be removed in Foundation 6.3.';
  @include flex-order($order);
}

/// Horizontally or vertically aligns the columns within a flex row. Apply this mixin to a flex row.
///
/// @param {Keyword} $x [null] - Horizontal alignment to use. Can be `left`, `right`, `center`, `justify`, or `spaced`. Or, set it to `null` (the default) to not set horizontal alignment.
/// @param {Keyword} $y [null] - Vertical alignment to use. Can be `top`, `bottom`, `middle`, or `stretch`. Or, set it to `null` (the default) to not set vertical alignment.
@mixin flex-grid-row-align($x: null, $y: null) {
  @warn 'This mixin is being replaced by flex-align(). flex-grid-row-align() will be removed in Foundation 6.3.';
  @include flex-align($x, $y);
}

/// Vertically align a single column within a flex row. Apply this mixin to a flex column.
///
/// @param {Keyword} $y [null] - Vertical alignment to use. Can be `top`, `bottom`, `middle`, or `stretch`. Or, set it to `null` (the default) to not set vertical alignment.
@mixin flex-grid-column-align($y: null) {
  @warn 'This mixin is being replaced by flex-align-self(). flex-grid-column-align() will be removed in Foundation 6.3.';
  @include flex-align-self($y);
}

@mixin foundation-flex-grid {
  // Row
  .row {
    @include flex-grid-row;

    // Nesting behavior
    & & {
      @include flex-grid-row(nest, $base: false);
    }

    // Expanded row
    &.expanded {
      max-width: none;
    }

    &.collapse {
      > .column { @include grid-col-collapse; }
    }
  }

  // Column
  .column {
    @include flex-grid-column;
  }

  // Column row
  // The double .row class is needed to bump up the specificity
  .column.row.row {
    float: none;
    display: block;

    // To properly nest a column row, padding and margin is removed
    .row & {
      padding-left: 0;
      padding-right: 0;
      margin-left: 0;
      margin-right: 0;
    }
  }

  @include -zf-each-breakpoint {
    @for $i from 1 through $grid-column-count {
      // Sizing (percentage)
      .#{$-zf-size}-#{$i} {
        flex: flex-grid-column($i);
        max-width: grid-column($i);
      }

      // Offsets
      $o: $i - 1;

      .#{$-zf-size}-offset-#{$o} {
        @include grid-column-offset($o);
      }
    }

    // Source ordering
    @for $i from 1 through 6 {
      .#{$-zf-size}-order-#{$i} {
        @include flex-order($i);
      }
    }

    // Block grid
    @for $i from 1 through $block-grid-max {
      .#{$-zf-size}-up-#{$i} {
        @include flex-grid-layout($i);
      }
    }

    @if $-zf-size != $-zf-zero-breakpoint {
      // Sizing (expand)
      @include breakpoint($-zf-size) {
        .#{$-zf-size}-expand {
          flex: flex-grid-column();
        }
      }

      // Auto-stacking/unstacking
      @at-root (without: media) {
        .row.#{$-zf-size}-unstack {
          > .column {
            flex: flex-grid-column(100%);

            @include breakpoint($-zf-size) {
              flex: flex-grid-column();
            }
          }
        }
      }
    }

    // Responsive collapsing
    .#{$-zf-size}-collapse {
      > .column { @include grid-col-collapse; }
    }

    .#{$-zf-size}-uncollapse {
      $gutter: -zf-get-bp-val($grid-column-gutter, $-zf-size);

      > .column { @include grid-col-uncollapse($gutter); }
    }
  }

  // Sizing (shrink)
  .shrink {
    flex: flex-grid-column(shrink);
    max-width: 100%;
  }

  // Vertical alignment using align-items and align-self
  // Remove these in 6.3
  @each $vdir, $prop in $-zf-flex-align {
    .column.align-#{$vdir} {
      @include flex-align-self($vdir);
    }
  }

  .columns {
    // scss-lint:disable PlaceholderInExtend
    @extend .column;
  }
}