Grid system

Use our powerful mobile-first flexbox grid to build layouts of all shapes and sizes thanks to a twelve column system, five default responsive tiers, Sass variables and mixins, and dozens of predefined classes.

Athena includes a powerful mobile-first flexbox grid system for building layouts of all shapes and sizes. It's based on a 12 column layout and has multiple tiers, one for each media query range. You can use it with Sass mixins or our predefined classes.

Contents

How it works

Athena's grid system uses a series of containers, rows, and columns to layout and align content. It's built with flexbox and is fully responsive. Below is an example and an in-depth look at how the grid comes together.

One of three columns
One of three columns
One of three columns

The above example creates three equal-width columns on small, medium, large, and extra large devices using our predefined grid classes. Those columns are centered in the page with the parent .container.

Breaking it down, here's how it works:

  • Containers provide a means to center your site's contents. Use .container for fixed width or .container-fluid for full width.
  • Rows are horizontal groups of columns that ensure your columns are lined up properly. We use the negative margin method on .row to ensure all your content is aligned properly down the left side.
  • Content should be placed within columns, and only columns may be immediate children of rows.
  • Thanks to flexbox, grid columns without a set width will automatically layout with equal widths. For example, four instances of .col-sm will each automatically be 25% wide for small breakpoints.
  • Column classes indicate the number of columns you'd like to use out of the possible 12 per row. So, if you want three equal-width columns, you can use .col-sm-4.
  • Column widths are set in percentages, so they're always fluid and sized relative to their parent element.
  • Columns have horizontal padding to create the gutters between individual columns, however, you can remove the margin from rows and padding from columns with .no-gutters on the .row.
  • There are five grid tiers, one for each responsive breakpoint: all breakpoints (extra small), small, medium, large, and extra large.
  • Grid tiers are based on minimum widths, meaning they apply to that one tier and all those above it (e.g., .col-sm-4 applies to small, medium, large, and extra large devices).
  • You can use predefined grid classes or Sass mixins for more semantic markup.

Be aware of the limitations and bugs around flexbox, like the inability to use some HTML elements as flex containers.

Sounds good? Great, let's move on to seeing all that in an example.

Grid options

While Athena uses ems or rems for defining most sizes, pxs are used for grid breakpoints and container widths. This is because the viewport width is in pixels and does not change with the font size.

See how aspects of the Athena grid system work across multiple devices with a handy table.

Extra small
<576px
Small
≥576px
Medium
≥768px
Large
≥992px
Extra large
≥1200px
Grid behavior Horizontal at all times Collapsed to start, horizontal above breakpoints
Max container width None (auto) 540px 720px 960px 1140px
Class prefix .col- .col-sm- .col-md- .col-lg- .col-xl-
# of columns 12
Gutter width 30px (15px on each side of a column)
Nestable Yes
Offsets Yes
Column ordering Yes

Auto-layout columns

Utilize breakpoint-specific column classes for easy column sizing without an explicit numbered class like .col-sm-6.

Equal-width

For example, here are two grid layouts that apply to every device and viewport, from xs to xl. Add any number of unit-less classes for each breakpoint you need and every column will be the same width.

1 of 2
2 of 2
1 of 3
2 of 3
3 of 3

<div class="container">
  <div class="row">
    <div class="col">
      1 of 2
    </div>
    <div class="col">
      2 of 2
    </div>
  </div>
  <div class="row">
    <div class="col">
      1 of 3
    </div>
    <div class="col">
      2 of 3
    </div>
    <div class="col">
      3 of 3
    </div>
  </div>
</div>

Equal-width columns can be broken into multiple lines, but there is a flexbox bug in Safari < 10.1 that prevents this from working without an explicit flex-basis or border. Our example works thanks to the border being set; you can do the same with .col { border: 1px solid transparent; }. Alternatively, you can set the flex-basis to the width of the column (e.g., .col { flex: 1 0 50%; }).

Both these fixes have been documented in a reduced test case outside Bootstrap.

Column
Column
Column
Column

<div class="container">
  <div class="row">
    <div class="col">Column</div>
    <div class="col">Column</div>
    <div class="w-100"></div>
    <div class="col">Column</div>
    <div class="col">Column</div>
  </div>
</div>

Setting one column width

Auto-layout for flexbox grid columns also means you can set the width of one column and have the sibling columns automatically resize around it. You may use predefined grid classes (as shown below), grid mixins, or inline widths. Note that the other columns will resize no matter the width of the center column.

1 of 3
2 of 3 (wider)
3 of 3
1 of 3
2 of 3 (wider)
3 of 3

<div class="container">
  <div class="row">
    <div class="col">
      1 of 3
    </div>
    <div class="col-6">
      2 of 3 (wider)
    </div>
    <div class="col">
      3 of 3
    </div>
  </div>
  <div class="row">
    <div class="col">
      1 of 3
    </div>
    <div class="col-5">
      2 of 3 (wider)
    </div>
    <div class="col">
      3 of 3
    </div>
  </div>
</div>

Variable width content

Use col-{breakpoint}-auto classes to size columns based on the natural width of their content. col-{breakpoint}-auto columns will never exceed the width of their parent container.

1 of 3
Variable width content
3 of 3
1 of 3
Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content
3 of 3
1 of 3
Variable width content
3 of 3

<div class="container">
  <div class="row justify-content-md-center">
    <div class="col col-lg-2">
      1 of 3
    </div>
    <div class="col-md-auto">
      Variable width content
    </div>
    <div class="col col-lg-2">
      3 of 3
    </div>
  </div>
  <div class="row justify-content-md-center">
    <div class="col col-lg-2">
      1 of 3
    </div>
    <div class="col-md-auto">
      Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content Variable width content
    </div>
    <div class="col col-lg-2">
      3 of 3
    </div>
  </div>
  <div class="row">
    <div class="col">
      1 of 3
    </div>
    <div class="col-md-auto">
      Variable width content
    </div>
    <div class="col col-lg-2">
      3 of 3
    </div>
  </div>
</div>

Equal-width multi-row

Create equal-width columns that span multiple rows by inserting a .w-100 where you want the columns to break to a new line. Make the breaks responsive by mixing the .w-100 with some responsive display utilities.

col
col
col
col

<div class="row">
  <div class="col">col</div>
  <div class="col">col</div>
  <div class="w-100"></div>
  <div class="col">col</div>
  <div class="col">col</div>
</div>

Responsive classes

Athena's grid includes five tiers of predefined classes for building complex responsive layouts. Customize the size of your columns on extra small, small, medium, large, or extra large devices however you see fit.

All breakpoints

For grids that are the same from the smallest of devices to the largest, use the .col and .col-* classes. Specify a numbered class when you need a particularly sized column; otherwise, feel free to stick to .col.

col
col
col
col
col-8
col-4

<div class="row">
  <div class="col">col</div>
  <div class="col">col</div>
  <div class="col">col</div>
  <div class="col">col</div>
</div>
<div class="row">
  <div class="col-8">col-8</div>
  <div class="col-4">col-4</div>
</div>

Stacked to horizontal

Using a single set of .col-sm-* classes, you can create a basic grid system that starts out stacked on extra small devices before becoming horizontal at the small breakpoint (sm).

col-sm-8
col-sm-4
col-sm
col-sm
col-sm

<div class="row">
  <div class="col-sm-8">col-sm-8</div>
  <div class="col-sm-4">col-sm-4</div>
</div>
<div class="row">
  <div class="col-sm">col-sm</div>
  <div class="col-sm">col-sm</div>
  <div class="col-sm">col-sm</div>
</div>

Mix and match

Don't want your columns to simply stack in some grid tiers? Use a combination of different classes for each tier as needed. See the example below for a better idea of how it all works.

.col-12 .col-md-8
.col-6 .col-md-4
.col-6 .col-md-4
.col-6 .col-md-4
.col-6 .col-md-4
.col-6
.col-6

<!-- Stack the columns on mobile by making one full-width and the other half-width -->
<div class="row">
  <div class="col-12 col-md-8">.col-12 .col-md-8</div>
  <div class="col-6 col-md-4">.col-6 .col-md-4</div>
</div>

<!-- Columns start at 50% wide on mobile and bump up to 33.3% wide on desktop -->
<div class="row">
  <div class="col-6 col-md-4">.col-6 .col-md-4</div>
  <div class="col-6 col-md-4">.col-6 .col-md-4</div>
  <div class="col-6 col-md-4">.col-6 .col-md-4</div>
</div>

<!-- Columns are always 50% wide, on mobile and desktop -->
<div class="row">
  <div class="col-6">.col-6</div>
  <div class="col-6">.col-6</div>
</div>

Alignment

Use flexbox alignment utilities to vertically and horizontally align columns.

Vertical alignment

One of three columns
One of three columns
One of three columns
One of three columns
One of three columns
One of three columns
One of three columns
One of three columns
One of three columns

<div class="container">
  <div class="row align-items-start">
    <div class="col">
      One of three columns
    </div>
    <div class="col">
      One of three columns
    </div>
    <div class="col">
      One of three columns
    </div>
  </div>
  <div class="row align-items-center">
    <div class="col">
      One of three columns
    </div>
    <div class="col">
      One of three columns
    </div>
    <div class="col">
      One of three columns
    </div>
  </div>
  <div class="row align-items-end">
    <div class="col">
      One of three columns
    </div>
    <div class="col">
      One of three columns
    </div>
    <div class="col">
      One of three columns
    </div>
  </div>
</div>
One of three columns
One of three columns
One of three columns

<div class="container">
  <div class="row">
    <div class="col align-self-start">
      One of three columns
    </div>
    <div class="col align-self-center">
      One of three columns
    </div>
    <div class="col align-self-end">
      One of three columns
    </div>
  </div>
</div>

Horizontal alignment

One of two columns
One of two columns
One of two columns
One of two columns
One of two columns
One of two columns
One of two columns
One of two columns
One of two columns
One of two columns

<div class="container">
  <div class="row justify-content-start">
    <div class="col-4">
      One of two columns
    </div>
    <div class="col-4">
      One of two columns
    </div>
  </div>
  <div class="row justify-content-center">
    <div class="col-4">
      One of two columns
    </div>
    <div class="col-4">
      One of two columns
    </div>
  </div>
  <div class="row justify-content-end">
    <div class="col-4">
      One of two columns
    </div>
    <div class="col-4">
      One of two columns
    </div>
  </div>
  <div class="row justify-content-around">
    <div class="col-4">
      One of two columns
    </div>
    <div class="col-4">
      One of two columns
    </div>
  </div>
  <div class="row justify-content-between">
    <div class="col-4">
      One of two columns
    </div>
    <div class="col-4">
      One of two columns
    </div>
  </div>
</div>

No gutters

The gutters between columns in our predefined grid classes can be removed with .no-gutters. This removes the negative margins from .row and the horizontal padding from all immediate children columns.

Here's the source code for creating these styles. Note that column overrides are scoped to only the first children columns and are targeted via attribute selector. While this generates a more specific selector, column padding can still be further customized with spacing utilities.


.no-gutters {
  margin-right: 0;
  margin-left: 0;


  > .col,
  > [class*="col-"] {
    padding-right: 0;
    padding-left: 0;
  }
}

In practice, here's how it looks. Note you can continue to use this with all other predefined grid classes (including column widths, responsive tiers, reorders, and more).

.col-12 .col-sm-6 .col-md-8
.col-6 .col-md-4

<div class="row no-gutters">
  <div class="col-12 col-sm-6 col-md-8">.col-12 .col-sm-6 .col-md-8</div>
  <div class="col-6 col-md-4">.col-6 .col-md-4</div>
</div>

Column wrapping

If more than 12 columns are placed within a single row, each group of extra columns will, as one unit, wrap onto a new line.

.col-9
.col-4
Since 9 + 4 = 13 > 12, this 4-column-wide div gets wrapped onto a new line as one contiguous unit.
.col-6
Subsequent columns continue along the new line.

<div class="row">
  <div class="col-9">.col-9</div>
  <div class="col-4">.col-4<br>Since 9 + 4 = 13 > 12, this 4-column-wide div gets wrapped onto a new line as one contiguous unit.</div>
  <div class="col-6">.col-6<br>Subsequent columns continue along the new line.</div>
</div>

Column breaks

Breaking columns to a new line in flexbox requires a small hack: add an element with width: 100% wherever you want to wrap your columns to a new line. Normally this is accomplished with multiple .rows, but not every implementation method can account for this.

.col-6 .col-sm-3
.col-6 .col-sm-3
.col-6 .col-sm-3
.col-6 .col-sm-3

<div class="row">
  <div class="col-6 col-sm-3">.col-6 .col-sm-3</div>
  <div class="col-6 col-sm-3">.col-6 .col-sm-3</div>

  <!-- Force next columns to break to new line -->
  <div class="w-100"></div>

  <div class="col-6 col-sm-3">.col-6 .col-sm-3</div>
  <div class="col-6 col-sm-3">.col-6 .col-sm-3</div>
</div>

You may also apply this break at specific breakpoints with our responsive display utilities.

.col-6 .col-sm-4
.col-6 .col-sm-4
.col-6 .col-sm-4
.col-6 .col-sm-4

<div class="row">
  <div class="col-6 col-sm-4">.col-6 .col-sm-4</div>
  <div class="col-6 col-sm-4">.col-6 .col-sm-4</div>

  <!-- Force next columns to break to new line at md breakpoint and up -->
  <div class="w-100 d-none d-md-block"></div>

  <div class="col-6 col-sm-4">.col-6 .col-sm-4</div>
  <div class="col-6 col-sm-4">.col-6 .col-sm-4</div>
</div>

Reordering

Flex order

Use flexbox utilities for controlling the visual order of your content.

First, but unordered
Second, but last
Third, but first

<div class="container">
  <div class="row">
    <div class="col flex-unordered">
      First, but unordered
    </div>
    <div class="col flex-last">
      Second, but last
    </div>
    <div class="col flex-first">
      Third, but first
    </div>
  </div>
</div>

Offsetting columns

Move columns to the right using .offset-md-* classes. These classes increase the left margin of a column by * columns. For example, .offset-md-4 moves .col-md-4 over four columns.

.col-md-4
.col-md-4 .offset-md-4
.col-md-3 .offset-md-3
.col-md-3 .offset-md-3
.col-md-6 .offset-md-3

<div class="row">
  <div class="col-md-4">.col-md-4</div>
  <div class="col-md-4 offset-md-4">.col-md-4 .offset-md-4</div>
</div>
<div class="row">
  <div class="col-md-3 offset-md-3">.col-md-3 .offset-md-3</div>
  <div class="col-md-3 offset-md-3">.col-md-3 .offset-md-3</div>
</div>
<div class="row">
  <div class="col-md-6 offset-md-3">.col-md-6 .offset-md-3</div>
</div>

Push and pull

Easily change the order of our built-in grid columns with .push-md-* and .pull-md-* modifier classes.

.col-md-9 .push-md-3
.col-md-3 .pull-md-9

<div class="row">
  <div class="col-md-9 push-md-3">.col-md-9 .push-md-3</div>
  <div class="col-md-3 pull-md-9">.col-md-3 .pull-md-9</div>
</div>

In addition to column clearing at responsive breakpoints, you may need to reset offsets, pushes, or pulls:

.col-sm-5 .col-md-6
.col-sm-5 .offset-sm-2 .col-md-6 .offset-md-0
.col.col-sm-6.col-md-5.col-lg-6
.col-sm-6 .col-md-5 .offset-md-2 .col-lg-6 .offset-lg-0

<div class="row">
  <div class="col-sm-5 col-md-6">.col-sm-5 .col-md-6</div>
  <div class="col-sm-5 offset-sm-2 col-md-6 offset-md-0">.col-sm-5 .offset-sm-2 .col-md-6 .offset-md-0</div>
</div>

<div class="row">
  <div class="col-sm-6 col-md-5 col-lg-6">.col.col-sm-6.col-md-5.col-lg-6</div>
  <div class="col-sm-6 col-md-5 offset-md-2 col-lg-6 offset-lg-0">.col-sm-6 .col-md-5 .offset-md-2 .col-lg-6 .offset-lg-0</div>
</div>

Nesting

To nest your content with the default grid, add a new .row and set of .col-sm-* columns within an existing .col-sm-* column. Nested rows should include a set of columns that add up to 12 or fewer (it is not required that you use all 12 available columns).

Level 1: .col-sm-9
Level 2: .col-8 .col-sm-6
Level 2: .col-4 .col-sm-6

<div class="row">
  <div class="col-sm-9">
    Level 1: .col-sm-9
    <div class="row">
      <div class="col-8 col-sm-6">
        Level 2: .col-8 .col-sm-6
      </div>
      <div class="col-4 col-sm-6">
        Level 2: .col-4 .col-sm-6
      </div>
    </div>
  </div>
</div>

Sass mixins

When using Athena's source Sass files, you have the option of using Sass variables and mixins to create custom, semantic, and responsive page layouts. Our predefined grid classes use these same variables and mixins to provide a whole suite of ready-to-use classes for fast responsive layouts.

Variables

Variables and maps determine the number of columns, the gutter width, and the media query point at which to begin floating columns. We use these to generate the predefined grid classes documented above, as well as for the custom mixins listed below.


$grid-columns:      12;
$grid-gutter-width-base: 30px;


$grid-gutter-widths: (
  xs: $grid-gutter-width-base, // 30px
  sm: $grid-gutter-width-base, // 30px
  md: $grid-gutter-width-base, // 30px
  lg: $grid-gutter-width-base, // 30px
  xl: $grid-gutter-width-base  // 30px
)


$grid-breakpoints: (
  // Extra small screen / phone
  xs: 0,
  // Small screen / phone
  sm: 576px,
  // Medium screen / tablet
  md: 768px,
  // Large screen / desktop
  lg: 992px,
  // Extra large screen / wide desktop
  xl: 1200px
);


$container-max-widths: (
  sm: 540px,
  md: 720px,
  lg: 960px,
  xl: 1140px
);

Mixins

Mixins are used in conjunction with the grid variables to generate semantic CSS for individual grid columns.


// Creates a wrapper for a series of columns
@include make-row($gutters: $grid-gutter-widths);


// Make the element grid-ready (applying everything but the width)
@include make-col-ready($gutters: $grid-gutter-widths);
@include make-col($size, $columns: $grid-columns);


// Get fancy by offsetting, or changing the sort order
@include make-col-offset($size, $columns: $grid-columns);
@include make-col-push($size, $columns: $grid-columns);
@include make-col-pull($size, $columns: $grid-columns);

Example usage

You can modify the variables to your own custom values, or just use the mixins with their default values. Here's an example of using the default settings to create a two-column layout with a gap between.


.example-container {
  width: 800px;
  @include make-container();
}


.example-row {
  @include make-row();
}


.example-content-main {
  @include make-col-ready();


  @include media-breakpoint-up(sm) {
    @include make-col(6);
  }
  @include media-breakpoint-up(lg) {
    @include make-col(8);
  }
}


.example-content-secondary {
  @include make-col-ready();


  @include media-breakpoint-up(sm) {
    @include make-col(6);
  }
  @include media-breakpoint-up(lg) {
    @include make-col(4);
  }
}

Customizing the grid

Using our built-in grid Sass variables and maps, it's possible to completely customize the predefined grid classes. Change the number of tiers, the media query dimensions, and the container widths—then recompile.

Columns and gutters

The number of grid columns and their horizontal padding (aka, gutters) can be modified via Sass variables. $grid-columns is used to generate the widths (in percent) of each individual column while $grid-gutter-widths allows breakpoint-specific widths that are divided evenly across padding-left and padding-right for the column gutters.


$grid-columns:               12 !default;
$grid-gutter-width-base:     30px !default;
$grid-gutter-widths: (
  xs: $grid-gutter-width-base,
  sm: $grid-gutter-width-base,
  md: $grid-gutter-width-base,
  lg: $grid-gutter-width-base,
  xl: $grid-gutter-width-base
) !default;

Grid tiers

Moving beyond the columns themselves, you may also customize the number of grid tiers. If you wanted just four grid tiers, you'd update the $grid-breakpoints and $container-max-widths to something like this:


$grid-breakpoints: (
  xs: 0,
  sm: 480px,
  md: 768px,
  lg: 1024px
);


$container-max-widths: (
  sm: 420px,
  md: 720px,
  lg: 960px
);

When making any changes to the Sass variables or maps, you'll need to save your changes and recompile. Doing so will output a brand new set of predefined grid classes for column widths, offsets, pushes, and pulls. Responsive visibility utilities will also be updated to use the custom breakpoints.