SnapKit/_sass/foundation/components/_grid.scss

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

@import 'global';

//
// @variables
//
$include-html-grid-classes: $include-html-classes !default;
$include-xl-html-grid-classes: false !default;

$row-width: rem-calc(1000) !default;
$total-columns: 12 !default;

$last-child-float: $opposite-direction !default;

//
// Grid Functions
//

// Deprecated: We'll drop support for this in 5.1, use grid-calc()
@function gridCalc($colNumber, $totalColumns) {
  @warn "gridCalc() is deprecated, use grid-calc()";
  @return grid-calc($colNumber, $totalColumns);
}

// @FUNCTION
// $colNumber - Found in settings file
// $totalColumns - Found in settings file
@function grid-calc($colNumber, $totalColumns) {
  $result: percentage(($colNumber / $totalColumns));
  @if $result == 0% { $result: 0; }
  @return $result;
}

//
// @mixins
//

// For creating container, nested, and collapsed rows.
//
//
// $behavior - Any special behavior for this row? Default: false. Options: nest, collapse, nest-collapse, false.
@mixin grid-row($behavior: false) {

  // use @include grid-row(nest); to include a nested row
  @if $behavior == nest {
    margin: 0 (-($column-gutter/2));
    max-width: none;
    width: auto;
  }

  // use @include grid-row(collapse); to collapsed a container row margins
  @else if $behavior == collapse {
    margin: 0;
    max-width: $row-width;
    width: 100%;
  }

  // use @include grid-row(nest-collapse); to collapse outer margins on a nested row
  @else if $behavior == nest-collapse {
    margin: 0;
    max-width: none;
    width: auto;
  }

  // use @include grid-row; to use a container row
  @else {
    margin: 0 auto;
    max-width: $row-width;
    width: 100%;
  }

  // Clearfix for all rows
  @include clearfix();
}

// Creates a column, should be used inside of a media query to control layouts
//
// $columns - The number of columns this should be
// $last-column - Is this the last column? Default: false.
// $center - Center these columns? Default: false.
// $offset - # of columns to offset. Default: false.
// $push - # of columns to push. Default: false.
// $pull - # of columns to pull. Default: false.
// $collapse - Get rid of gutter padding on column? Default: false.
// $float - Should this float? Default: true. Options: true, false, left, right.
@mixin grid-column(
  $columns:false,
  $last-column:false,
  $center:false,
  $offset:false,
  $push:false,
  $pull:false,
  $collapse:false,
  $float:true,
  $position:false) {

  // If positioned for default .column, include relative position
  // push and pull require position set
  @if $position or $push or $pull {
    position: relative;
  }

  // If collapsed, get rid of gutter padding
  @if $collapse {
    padding-left: 0;
    padding-right: 0;
  }

  // Gutter padding whenever a column isn't set to collapse
  // (use $collapse:null to do nothing)
  @else if $collapse == false {
    padding-left: ($column-gutter / 2);
    padding-right: ($column-gutter / 2);
  }

  // If a column number is given, calculate width
  @if $columns {
    width: grid-calc($columns, $total-columns);

    // If last column, float naturally instead of to the right
    @if $last-column { float: $opposite-direction; }
  }

  // Source Ordering, adds left/right depending on which you use.
  @if $push { #{$default-float}: grid-calc($push, $total-columns); #{$opposite-direction}: auto; }
  @if $pull { #{$opposite-direction}: grid-calc($pull, $total-columns); #{$default-float}: auto; }

  @if $float {
    @if $float == left or $float == true { float: $default-float; }
    @else if $float == right { float: $opposite-direction; }
    @else { float: none; }
  }

  // If centered, get rid of float and add appropriate margins
  @if $center {
    margin-#{$default-float}: auto;
    margin-#{$opposite-direction}: auto;
    float: none;
  }

  // If offset, calculate appropriate margins
  @if $offset { margin-#{$default-float}: grid-calc($offset, $total-columns) !important; }

}

// Create presentational classes for grid
//
// $size - Name of class to use, i.e. "large" will generate .large-1, .large-2, etc.
@mixin grid-html-classes($size) {

  @for $i from 0 through $total-columns - 1 {
    .#{$size}-push-#{$i} {
      @include grid-column($push:$i, $collapse:null, $float:false);
    }
    .#{$size}-pull-#{$i} {
      @include grid-column($pull:$i, $collapse:null, $float:false);
    }
  }

  .column,
  .columns { @include grid-column($columns:false, $position:true); }


  @for $i from 1 through $total-columns {
    .#{$size}-#{$i} { @include grid-column($columns:$i, $collapse:null, $float:false); }
  }

  @for $i from 0 through $total-columns - 1 {
    .#{$size}-offset-#{$i} { @include grid-column($offset:$i, $collapse:null, $float:false); }
  }

  .#{$size}-reset-order {
    float: $default-float;
    left: auto;
    margin-#{$default-float}: 0;
    margin-#{$opposite-direction}: 0;
    right: auto;
  }

  .column.#{$size}-centered,
  .columns.#{$size}-centered { @include grid-column($center:true, $collapse:null, $float:false); }

  .column.#{$size}-uncentered,
  .columns.#{$size}-uncentered {
    float: $default-float;
    margin-#{$default-float}: 0;
    margin-#{$opposite-direction}: 0;
  }

  // Fighting [class*="column"] + [class*="column"]:last-child
  .column.#{$size}-centered:last-child,
  .columns.#{$size}-centered:last-child{
    float: none;
  }

  // Fighting .column.<previous-size>-centered:last-child
  .column.#{$size}-uncentered:last-child,
  .columns.#{$size}-uncentered:last-child {
    float: $default-float;
  }

  .column.#{$size}-uncentered.opposite,
  .columns.#{$size}-uncentered.opposite {
    float: $opposite-direction;
  }

	.row {
		&.#{$size}-collapse {
			> .column,
			> .columns { @include grid-column($collapse:true, $float:false); }

			.row {margin-left:0; margin-right:0;}
		}
		&.#{$size}-uncollapse {
			> .column,
			> .columns {
				@include grid-column;
			}
		}
	}
}

@include exports("grid") {
  @if $include-html-grid-classes {
    .row {
      @include grid-row;

      &.collapse {
         > .column,
         > .columns { @include grid-column($collapse:true, $float:false); }

        .row {margin-left:0; margin-right:0;}
      }

      .row { @include grid-row($behavior:nest);
        &.collapse { @include grid-row($behavior:nest-collapse); }
      }
    }

    .column,
    .columns { @include grid-column($columns:$total-columns); }

    [class*="column"] + [class*="column"]:last-child { float: $last-child-float; }
    [class*="column"] + [class*="column"].end { float: $default-float; }

    @media #{$small-up} {
      @include grid-html-classes($size:small);
    }

    @media #{$medium-up} {
      @include grid-html-classes($size:medium);
      // Old push and pull classes
      @for $i from 0 through $total-columns - 1 {
        .push-#{$i} {
          @include grid-column($push:$i, $collapse:null, $float:false);
        }
        .pull-#{$i} {
          @include grid-column($pull:$i, $collapse:null, $float:false);
        }
      }
    }
    @media #{$large-up} {
      @include grid-html-classes($size:large);
      @for $i from 0 through $total-columns - 1 {
        .push-#{$i} {
          @include grid-column($push:$i, $collapse:null, $float:false);
        }
        .pull-#{$i} {
          @include grid-column($pull:$i, $collapse:null, $float:false);
        }
      }
    }
  }
  @if $include-xl-html-grid-classes {
    @media #{$xlarge-up} {
      @include grid-html-classes($size:xlarge);
    }
    @media #{$xxlarge-up} {
      @include grid-html-classes($size:xxlarge);
    }
  }
}