The grid is 12 columns and percentage-based. The number of columns a container spans can be adjusted across breakpoints for responsive layouts. The grid system works with a variety of layout utilities to achieve different results.

Float based grid

Use .clearfix on the container and float utilities with columns for a floated grid layout.

<div class="container-lg clearfix">
  <div class="col-4 float-left border p-4">
    My column
  </div>
  <div class="col-4 float-left border p-4">
    Looks better
  </div>
  <div class="col-4 float-left border p-4">
    Than your column
  </div>
</div>

Reversed grid

To reverse the order of columns, use float-right to float columns to the right.

<div class="container-lg clearfix">
  <div class="col-4 float-right border p-4">
    One
  </div>
  <div class="col-4 float-right border p-4">
    Two
  </div>
  <div class="col-4 float-right border p-4">
    Three
  </div>
</div>

Nesting

You can infinitely nest grid layouts within other columns since the column widths are percentage based. With great flexibility comes great responsibility - be sensible with how far you nest!

<div class="clearfix">
  <div class="col-6 float-left px-1">
    <div class="border p-1">Unnested</div>
  </div>
  <div class="col-6 float-left">
    <div class="clearfix">
      <div class="col-6 float-left px-1">
        <div class="border p-1">1 x Nested</div>
      </div>
      <div class="col-6 float-left">
        <div class="col-6 float-left px-1">
          <div class="border p-1">2 x Nested</div>
        </div>
        <div class="col-6 float-left px-1">
          <div class="border p-1">2 x Nested</div>
        </div>
      </div>
    </div>
  </div>
</div>

Centering a column

Use .mx-auto to center columns within a container.

<div class="border">
  <div class="col-6 p-2 mx-auto border">
    This column is the center of my world.
  </div>
</div>

Column widths

Column widths can be used with any other block or inline-block elements to add percentage-based widths.

<div>
  <div class="col-4 float-right p-2 border text-red">
    <%= octicon "heart" %> Don't go bacon my heart.
  </div>
  <p>T-bone drumstick alcatra ribeye. Strip steak chuck andouille tenderloin bacon tri-tip ball tip beef capicola rump. Meatloaf bresaola drumstick ball tip salami. Drumstick ham bacon alcatra pig porchetta, spare ribs leberkas pork belly.</p>
</div>

Offset columns

Using column offset classes can push a div over X number of columns. They work responsively using the breakpoints outlined below.

<div class="clearfix">
  <div class="offset-1 col-3 border p-3">.offset-1</div>
  <div class="offset-2 col-3 border p-3">.offset-2</div>
</div>

Gutters

Use gutter styles or padding utilities to create gutters. You can use the default gutter style, gutter, or either of its modifiers, gutter-condensed or gutter-spacious. Gutter styles also support responsive breakpoint modifiers. Gutter styles add padding to the left and right side of each column and apply a negative margin to the container to ensure content inside each column lines up with content outside of the grid.

<div class="clearfix gutter-md-spacious border">
  <div class="col-3 float-left">
    <div class="border p-3">.col-md-3</div>
  </div>
  <div class="col-3 float-left">
    <div class="border p-3">.col-md-3</div>
  </div>
  <div class="col-3 float-left">
    <div class="border p-3">.col-md-3</div>
  </div>
  <div class="col-3 float-left">
    <div class="border p-3">.col-md-3</div>
  </div>
</div>

Use padding utilities to create gutters for more customized layouts.

<div class="container-lg clearfix">
  <div class="col-3 float-left pr-2 mb-3">
    <div class="border bg-gray-light">.pr-2</div>
  </div>
  <div class="col-3 float-left px-2 mb-3">
    <div class="border bg-gray-light">.px-2</div>
  </div>
  <div class="col-3 float-left px-2 mb-3">
    <div class="border bg-gray-light">.px-2</div>
  </div>
  <div class="col-3 float-left pl-2 mb-3">
    <div class="border bg-gray-light">.pl-2</div>
  </div>
</div>
<div class="container-lg clearfix">
  <div class="col-3 float-left pr-2">
    <div class="border bg-gray-light">.pr-2</div>
  </div>
  <div class="col-9 float-left pl-2">
    <div class="border bg-gray-light">.pl-2</div>
  </div>
</div>

Inline-block grids

Use column widths with d-inline-block as an alternative to floated grids.

<div>
  <div class="col-4 d-inline-block border">
    .col-4 .d-inline-block
  </div><!--
  --><div class="col-4 d-inline-block border">
    .col-4 .d-inline-block
  </div><!--
  --><div class="col-4 d-inline-block border">
    .col-4 .d-inline-block
  </div>
</div>

You can use column widths and other utilities on elements such as lists to create the layout you need while keeping the markup semantically correct.

<ul class="list-style-none">
  <li class="d-inline-block col-2 p-2"><img class="width-full avatar" src="/broccolini.png" alt="broccolini" /></li><!--
  --><li class="d-inline-block col-2 p-2"><img class="width-full avatar" src="/jonrohan.png" alt="jonrohan" /></li><!--
  --><li class="d-inline-block col-2 p-2"><img class="width-full avatar" src="/muan.png" alt="muan" /></li><!--
  --><li class="d-inline-block col-2 p-2"><img class="width-full avatar" src="/pmarsceill.png" alt="pmarsceill" /></li><!--
  --><li class="d-inline-block col-2 p-2"><img class="width-full avatar" src="/sophshep.png" alt="sophshep" /></li><!--
  --><li class="d-inline-block col-2 p-2"><img class="width-full avatar" src="/cmwinters.png" alt="cmwinters" /></li><!--
  --><li class="d-inline-block col-2 p-2"><img class="width-full avatar" src="/jeejkang.png" alt="jeejkang" /></li><!--
  --><li class="d-inline-block col-2 p-2"><img class="width-full avatar" src="/mdo.png" alt="mdo" /></li>
</ul>

Display table grids

Using display table utilities with columns gives you some alternative layout options.

A useful example is being able to keep the height of the container equal across a row when the length of content may differ.

<div class="d-table col-12">
  <div class="col-4 d-table-cell border p-2">
    Bacon ipsum dolor amet leberkas pork pig kielbasa shankle ribeye meatball, salami alcatra venison.
  </div><!--
  --><div class="col-4 d-table-cell border p-2">
    Pork chop cupim cow turkey frankfurter, landjaeger fatback hamburger meatball salami spare ribs. Rump tenderloin salami, hamburger frankfurter landjaeger andouille.
  </div><!--
  --><div class="col-4 d-table-cell border p-2">
    Brisket tongue frankfurter cupim strip steak rump picanha pancetta pork pig kevin pastrami biltong. Shankle venison meatball swine sausage ground round. Tail pork loin ribeye kielbasa short ribs pork chop.
  </div>
</div>

You can also create an alternative media object layout with .display-table and column widths.

<div class="d-table col-12">
  <div class="col-2 d-table-cell v-align-middle">
    <img class="width-full avatar" src="/github.png" alt="github" />
  </div>
  <div class="col-10 d-table-cell v-align-middle pl-4">
    <h1 class="text-normal lh-condensed">GitHub</h1>
    <p class="h4 text-gray text-normal mb-2">How people build software.</p>
    <a class="text-gray text-small" href="#url">https://github.com/about</a>
  </div>
</div>

Note that table cells will fill the width of their container even when the total columns doesn’t add up to 12.

<div class="d-table col-12">
  <div class="col-4 d-table-cell border">
    .col-4 .d-table-cell
  </div><!--
  --><div class="col-4 d-table-cell border">
    .col-4 .d-table-cell
  </div><!--
  --><div class="col-2 d-table-cell border">
    .col-2 .d-table-cell
  </div>
</div>

Flexbox grids

You can use flex utilities on the container and columns to create a flexbox grid.

This can be useful for keeping columns the same height, justifying content and vertically aligning items. The flexbox grid is also great for working with responsive layouts.

<div class="d-flex flex-column flex-md-row flex-items-center flex-md-items-center">
  <div class="col-2 d-flex flex-items-center flex-items-center flex-md-items-start">
    <img class="width-full avatar mb-2 mb-md-0" src="/github.png" alt="github" />
  </div>
  <div class="col-12 col-md-10 d-flex flex-column flex-justify-center flex-items-center flex-md-items-start pl-md-4">
    <h1 class="text-normal lh-condensed">GitHub</h1>
    <p class="h4 text-gray text-normal mb-2">How people build software.</p>
    <a class="text-gray text-small" href="#url">https://github.com/about</a>
  </div>
</div>

Responsive grids

All the column width classes can be set per breakpoint to create responsive grid layouts. Each responsive style is applied to the specified breakpoint and up.

Breakpoints

We use abbreviations for each breakpoint to keep the class names concise.

Shorthand Description
sm min-width: 544px
md min-width: 768px
lg min-width: 1004px
xl min-width: 1280px

Note: The lg breakpoint matches our current page width of 980px including left and right padding of 12px. This is so that content doesn’t touch the edges of the window when resized.


In this example at the sm breakpoint 2 columns will show, at the md breakpoint 4 columns will show, and at the lg breakpoint 6 columns will show.

<div class="container-lg clearfix">
  <div class="col-sm-6 col-md-3 col-lg-2 float-left p-2 border">
    .col-sm-6 .col-md-3 .col-lg-2
  </div>
  <div class="col-sm-6 col-md-3 col-lg-2 float-left p-2 border">
    .col-sm-6 .col-md-3 .col-lg-2
  </div>
  <div class="col-sm-6 col-md-3 col-lg-2 float-left p-2 border">
    .col-sm-6 .col-md-3 .col-lg-2
  </div>
  <div class="col-sm-6 col-md-3 col-lg-2 float-left p-2 border">
    .col-sm-6 .col-md-3 .col-lg-2
  </div>
  <div class="col-sm-6 col-md-3 col-lg-2 float-left p-2 border">
    .col-sm-6 .col-md-3 .col-lg-2
  </div>
  <div class="col-sm-6 col-md-3 col-lg-2 float-left p-2 border">
    .col-sm-6 .col-md-3 .col-lg-2
  </div>
</div>

For demonstration, this is how the above example would look at the sm breakpoint.

<div class="container-lg clearfix">
  <div class="col-sm-6 float-left p-2 border">
    .col-sm-6
  </div>
  <div class="col-sm-6 float-left p-2 border">
    .col-sm-6
  </div>
  <div class="col-sm-6 float-left p-2 border">
    .col-sm-6
  </div>
  <div class="col-sm-6 float-left p-2 border">
    .col-sm-6
  </div>
  <div class="col-sm-6 float-left p-2 border">
    .col-sm-6
  </div>
  <div class="col-sm-6 float-left p-2 border">
    .col-sm-6
  </div>
</div>

This is how that same example would look at the md breakpoint.

<div class="container-lg clearfix">
  <div class="col-md-3 float-left p-2 border">
    .col-md-3
  </div>
  <div class="col-md-3 float-left p-2 border">
    .col-md-3
  </div>
  <div class="col-md-3 float-left p-2 border">
    .col-md-3
  </div>
  <div class="col-md-3 float-left p-2 border">
    .col-md-3
  </div>
  <div class="col-md-3 float-left p-2 border">
    .col-md-3
  </div>
  <div class="col-md-3 float-left p-2 border">
    .col-md-3
  </div>
</div>

This is how that example would look at the lg breakpoint.

<div class="container-lg clearfix">
  <div class="col-lg-2 float-left p-2 border">
    .col-lg-2
  </div>
  <div class="col-lg-2 float-left p-2 border">
    .col-lg-2
  </div>
  <div class="col-lg-2 float-left p-2 border">
    .col-lg-2
  </div>
  <div class="col-lg-2 float-left p-2 border">
    .col-lg-2
  </div>
  <div class="col-lg-2 float-left p-2 border">
    .col-lg-2
  </div>
  <div class="col-lg-2 float-left p-2 border">
    .col-lg-2
  </div>
</div>

Containers

Container widths match our breakpoints and are available at a md, lg, and xl size. Containers apply a max-width rather than a fixed width for responsive layouts, and they center the container.

<div class="container-md border">
  .container-md, max-width 768px
</div>

<div class="container-lg border">
  .container-lg, max-width 1012px
</div>

<div class="container-xl border">
  .container-xl, max-width 1280px
</div>

Note: .container is being replaced with .container-lg. To match the current fixed page width use .container-lg with px-3. This gives the container padding on smaller screens which works better for responsive layouts.