css/docs/content/utilities/layout.md

title	path	status	source	bundle
Layout	utilities/layout	Stable	https://github.com/primer/css/blob/main/src/utilities/layout.scss	utilities

Change the document layout with display, float, alignment, and other utilities.

Display

Adjust the display of an element with .d-block, .d-none, .d-inline, .d-inline-block, .d-table, .d-table-cell utilities.

<div class="d-inline border">
  .d-inline
  <div class="d-inline-block border">
    .d-inline-block
  </div>
  <span class="d-block border">.d-block</span>
  <div class="d-table border">
    <div class="d-table-cell border">
      .d-table-cell
    </div>
  </div>
  <div class="d-table-cell border">
    .d-table-cell
  </div>
  <div class="d-none">
    .d-none
  </div>
</div>

The HTML hidden attribute

As of Primer v10.10.0, primer-base includes a rule that sets display: none !important for any element with the hidden attribute. You can safely use the hidden attribute with display utilities, but we suggest:

1. Use the hidden attribute (and corresponding JavaScript property) if you're going to programmatically show and hide content.
2. Use d-none and/or its responsive variants (d-sm-block, d-lg-none) to conditionally show content at different screen sizes.

Rather than toggling the d-none class in JavaScript, you should toggle the hidden property on an element. This means that you won't have to restore any more specific display utility (d-inline or d-flex, for instance) just to work around the order in which they're listed in the stylesheet.

// Good:
element.hidden = !visible

// Bad:
element.classList.toggle('d-none', !visible)
element.classList.toggle('d-inline', visible)

display:table wrapping issues

There are known issues with using display:table and wrapping long strings, particularly in Firefox. You may need to use table-fixed on elements with d-table and apply column widths to table cells, which you can do with our column width styles.

<div class="d-table table-fixed width-full">
  <div class="d-table-cell border">
    .d-table-cell
  </div>
  <div class="d-table-cell col-10 border">
    d-table-cell .col-10
  </div>
</div>

Responsive display

A selection of display utilities are able to be applied or changed per breakpoint. .d-block, .d-none, .d-inline, and .d-inline-block are available as responsive utilities using the following formula: d-[breakpoint]-[property]. For example: d-md-inline-block. Each responsive display utility is applied to the specified breakpoint and up.

In the following example, the ul element switches from display: block on mobile to display: inline-block at the md breakpoint, while the list items remain inline.

<h5 class="d-md-inline-block">.d-md-inline-block</h5>
<ul class="d-md-inline-block border">
  <li class="d-inline border">.d-inline</li>
  <li class="d-inline border">.d-inline</li>
</ul>

Responsive hide

Hide utilities are able to be applied or changed per breakpoint using the following formula:
hide-[breakpoint], for example: hide-sm. Hide utilities act differently from other responsive styles and are applied to each breakpoint-range only.

Shorthand	Range
-sm	0—543px
-md	544px—767px
-lg	768px—1011px
-xl	1012px and above

<div>
  <h3>Potato update</h3>
  <span class="hide-sm hide-md">Opened by <a href="#url">broccolini</a></span>
  <span class="d-md-none">Updated</span> 3 hours ago
</div>

Text direction

.direction-ltr or .direction-rtl can be used to change the text direction. This is especially helpful when paired with .d-table, .d-table-cell, and .v-align-middle to create equal height, vertically centered, alternating content.

Visibility

Adjust the visibility of an element with .v-hidden and .v-visible.

Overflow

Adjust element overflow with .overflow-hidden, .overflow-scroll, and .overflow-auto, or use .overflow-visible to undo the effects of CSS with overflow issues. .overflow-hidden can also be used to create a new block formatting context or clear floats.

Overflow utilities can also target x- and y-axes independently via:

• .overflow-x-auto
• .overflow-x-hidden
• .overflow-x-scroll
• .overflow-x-visible
• .overflow-y-auto
• .overflow-y-hidden
• .overflow-y-scroll
• .overflow-y-visible

Overflow utilities can be applied or changed per breakpoint. Each responsive overflow utility is applied to the specified breakpoint and up, using the following formula: overflow-[breakpoint]-[axis]-[property]. For example: overflow-x-scroll or overflow-md-x-visible.

Floats

Using floats are discouraged since flexbox offers more features and doesn't need to be cleared. If you still need it, you can use .float-left and .float-right to set floats, and .clearfix to clear.

<div class="clearfix border">
  <div class="float-left border">
    .float-left
  </div>
  <div class="float-right border">
    .float-right
  </div>
</div>

Responsive floats

Float utilities can be applied or changed per breakpoint. This can be useful for responsive layouts when you want an element to be full width on mobile but floated at a larger breakpoint.

Each responsive float utility is applied to the specified breakpoint and up, using the following formula: float-[breakpoint]-[property]. For example: float-md-left. Remember to use .clearfix to clear.

<div class="clearfix border">
  <div class="float-md-left border">
    .float-md-left
  </div>
  <div class="float-md-right border">
    .float-md-right
  </div>
</div>

Alignment

Adjust the alignment of an element with .v-align-baseline, .v-align-top, .v-align-middle or .v-align-bottom. The vertical-align property only applies to inline or table-cell boxes.

<div class="d-table border">
  <div class="d-table-cell"><h1>Potatoes</h1></div>
  <div class="d-table-cell v-align-baseline">.v-align-baseline</div>
  <div class="d-table-cell v-align-top">.v-align-top</div>
  <div class="d-table-cell v-align-middle">.v-align-middle</div>
  <div class="d-table-cell v-align-bottom">.v-align-bottom</div>
</div>

Use v-align-text-top or v-align-text-bottom to adjust the alignment of an element with the top or bottom of the parent element's font.

<div class="border">
  <h1 class="mr-1">Potatoes
    <span class="f4 v-align-text-top mr-1">.v-align-text-top</span>
    <span class="f4 v-align-text-bottom mr-1">.v-align-text-bottom</span>
  </h1>
</div>

Width and height

Use .width-fit to set max-width 100%.

<div class="one-fourth column">
  <img class="width-fit color-bg-subtle" src="https://github.com/github.png" alt="width fitted octocat" />
</div>

Use .width-full to set width to 100%.

<div class="d-table width-full">
  <div class="d-table-cell">
    <input class="form-control width-full" type="text" value="Full width form field" aria-label="Sample full width form field">
  </div>
</div>

Use .width-auto to reset width to auto (initial value). Typically used with responsive variants. Resize the window to see the effect in the example below.

<div class="d-table width-full width-md-auto">
  <div class="d-table-cell">
    <input class="form-control width-full" type="text" value="Responsive width form field" aria-label="Sample full responsive width form field">
  </div>
</div>

Use .height-fit to set max-height 100%.

<div class="one-fourth column" style="height: 100px; overflow: auto;">
  <div class="p-3 height-fit border">
    Bacon ipsum dolor amet meatball flank beef tail pig boudin ham hock chicken capicola. Shoulder ham spare ribs turducken pork tongue. Bresaola corned beef sausage jowl ribeye kielbasa tenderloin andouille leberkas tongue. Ribeye tri-tip tenderloin pig, chuck ground round chicken tongue corned beef biltong.
  </div>
</div>

Use .height-full to set height to 100%.

<div class="d-table border">
  <div class="d-table-cell height-full v-align-middle pl-3">
    <!-- <%= octicon "three-bars" %> -->
    <svg class="octicon octicon-three-bars" viewBox="0 0 12 16" version="1.1" width="12" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M11.41 9H.59C0 9 0 8.59 0 8c0-.59 0-1 .59-1H11.4c.59 0 .59.41.59 1 0 .59 0 1-.59 1h.01zm0-4H.59C0 5 0 4.59 0 4c0-.59 0-1 .59-1H11.4c.59 0 .59.41.59 1 0 .59 0 1-.59 1h.01zM.59 11H11.4c.59 0 .59.41.59 1 0 .59 0 1-.59 1H.59C0 13 0 12.59 0 12c0-.59 0-1 .59-1z"></path></svg>
  </div>
  <div class="p-3">
    Bacon ipsum dolor amet meatball flank beef tail pig boudin ham hock chicken capicola. Shoulder ham spare ribs turducken pork tongue. Bresaola corned beef sausage jowl ribeye kielbasa tenderloin andouille leberkas tongue. Ribeye tri-tip tenderloin pig, chuck ground round chicken tongue corned beef biltong.
  </div>
</div>

Position

Position utilities can be used to alter the default document flow. Be careful when using positioning, it's often unnecessary and commonly misused.

The position of an element depends on the content. Use top-0, right-0, bottom-0, and left-0 to further specify an elements final position.

<div style="height: 64px;">
  <div class="border position-absolute top-0 left-0">
    .top-0 .left-0
  </div>
  <div class="border position-absolute top-0 right-0">
    .top-0 .right-0
  </div>
  <div class="border position-absolute bottom-0 right-0">
    .bottom-0 .right-0
  </div>
  <div class="border position-absolute bottom-0 left-0">
    .bottom-0 .left-0
  </div>
</div>

Using the responsive variants (e.g. .right-md-0) can be helpful for positioning select menus, dropdowns, popovers etc. when the content gets shuffled around for certain responsive breakpoints. You can also use auto to "reset" a final position for wider breakpoints (e.g. right-0 right-md-auto).

Relative

Use .position-relative to create a new stacking context.

Note how the other elements are displayed as if "Two" were in its normal position and taking up space.

<div class="d-inline-block float-left color-bg-accent-emphasis color-fg-on-emphasis m-3" style="width:100px; height:100px;">
  One
</div>
<div class="d-inline-block float-left position-relative color-bg-accent-emphasis color-fg-on-emphasis m-3" style="width:100px; height:100px; top:12px; left:12px;">
  Two
</div>
<div class="d-inline-block float-left color-bg-accent-emphasis color-fg-on-emphasis m-3" style="width:100px; height:100px;">
  Three
</div>
<div class="d-inline-block float-left color-bg-accent-emphasis color-fg-on-emphasis m-3" style="width:100px; height:100px;">
  Four
</div>

Absolute

Use .position-absolute to take elements out of the normal document flow.

<div class="position-relative" style="height:116px;">
  <button type="button" class="btn mb-1">Button</button>
  <div class="position-absolute border p-2">
    <a href="#url" class="d-block p-1">Mashed potatoes</a>
    <a href="#url" class="d-block p-1">Fries</a>
  </div>
</div>

Fixed

Use .position-fixed to position an element relative to the viewport. Be careful when using fixed positioning. It is tricky to use and can lead to unwanted side effects.

Note: This example is shown in an <iframe> and therefore will not be positioned to the viewport of this page.

<div style="height: 64px;">
  <div class="position-fixed right-0 bottom-0 color-bg-subtle border p-2">
    .position-fixed
  </div>
</div>

To fill an entire width or height, use opposing directions.

Note: fixed positioning has been disabled here for demonstration only.

<div class="position-fixed left-0 right-0 p-3 color-bg-accent-emphasis color-fg-on-emphasis">
  .position-fixed .left-0 .right-0
</div>

Sticky

Use .position-sticky to keep an element stuck to an edge as long as its parent is visible. Things to keep in mind:

• Using the .position-sticky class by itself doesn't have any effect. An additional [top|bottom|left|right]-0 class is needed. See the examples below.
• Add a background color to sticky elements so it covers the content underneath.
• Use style="z-index: 1;" (or higher) in case there are other elements with z-index.

Top

Combine .position-sticky with .top-0 to keep an element stuck to the top.

<section class="mb-3">
  <header class="border position-sticky top-0 color-bg-subtle p-3" style="z-index: 1;">Sticky header 1</header>
  <main class="border border-top-0 p-3">
    <p>Until recently, the prevailing view assumed lorem ipsum was born as a nonsense text. “It's not Latin, though it looks like it, and it actually says nothing,” Before & After magazine answered a curious reader, “Its ‘words’ loosely approximate the frequency with which letters occur in English, which is why at a glance it looks pretty real.”</p>
  </main>
</section>

<section class="mb-3">
  <header class="border position-sticky top-0 color-bg-subtle p-3">Sticky header 2</header>
  <main class="border border-top-0 p-3">
    <p>As Cicero would put it, “Um, not so fast.”</p>

    <p>The placeholder text, beginning with the line “Lorem ipsum dolor sit amet, consectetur adipiscing elit”, looks like Latin because in its youth, centuries ago, it was Latin.</p>
  </main>
</section>

<section class="mb-3">
  <header class="border position-sticky top-0 color-bg-subtle p-3">Sticky header 3</header>
  <main class="border border-top-0 p-3">
    <p>Richard McClintock, a Latin scholar from Hampden-Sydney College, is credited with discovering the source behind the ubiquitous filler text. In seeing a sample of lorem ipsum, his interest was piqued by consectetur—a genuine, albeit rare, Latin word. Consulting a Latin dictionary led McClintock to a passage from De Finibus Bonorum et Malorum (“On the Extremes of Good and Evil”), a first-century B.C. text from the Roman philosopher Cicero.</p>
  </main>
</section>

<style>.frame-example { max-width: 300px; height: 300px; }</style>

Bottom

Combine .position-sticky with .bottom-0 to keep an element stuck to the bottom. Can be used as a footer or toolbar.

<section class="mb-3">
  <main class="border border-bottom-0 p-3">
    <h3>Title</h3>
    <p>Until recently, the prevailing view assumed lorem ipsum was born as a nonsense text. “It's not Latin, though it looks like it, and it actually says nothing,” Before & After magazine answered a curious reader, “Its ‘words’ loosely approximate the frequency with which letters occur in English, which is why at a glance it looks pretty real.”</p>
  </main>
  <footer class="border position-sticky bottom-0 color-bg-subtle p-3">Sticky footer 1</footer>
</section>

<section class="mb-3">
  <main class="border border-bottom-0 p-3">
    <h3>Title</h3>
    <p>Richard McClintock, a Latin scholar from Hampden-Sydney College, is credited with discovering the source behind the ubiquitous filler text. In seeing a sample of lorem ipsum, his interest was piqued by consectetur—a genuine, albeit rare, Latin word. Consulting a Latin dictionary led McClintock to a passage from De Finibus Bonorum et Malorum (“On the Extremes of Good and Evil”), a first-century B.C. text from the Roman philosopher Cicero.</p>
  </main>
  <footer class="border position-sticky bottom-0 color-bg-subtle p-3">Sticky footer 2</footer>
</section>

<style>.frame-example { max-width: 300px; height: 300px; }</style>

Left and right

Combine .position-sticky with .left-0 or .right-0 to keep elements stuck to the left or right when scrolling horizontally.

<div class="d-flex border overflow-x-auto">
  <section class="d-flex">
    <span class="border position-sticky left-0 color-bg-subtle p-4">A</span>
    <span class="border p-4">1</span><span class="border p-4">2</span><span class="border p-4">3</span><span class="border p-4">4</span><span class="border p-4">5</span><span class="border p-4">6</span><span class="border p-4">7</span><span class="border p-4">8</span><span class="border p-4">9</span>
  </section>
  <section class="d-flex">
    <span class="border position-sticky left-0 color-bg-subtle p-4">B</span>
    <span class="border p-4">1</span><span class="border p-4">2</span><span class="border p-4">3</span><span class="border p-4">4</span><span class="border p-4">5</span><span class="border p-4">6</span><span class="border p-4">7</span><span class="border p-4">8</span><span class="border p-4">9</span>
  </section>
  <section class="d-flex">
    <span class="border position-sticky left-0 color-bg-subtle p-4">C</span>
    <span class="border p-4">1</span><span class="border p-4">2</span><span class="border p-4">3</span><span class="border p-4">4</span><span class="border p-4">5</span><span class="border p-4">6</span><span class="border p-4">7</span><span class="border p-4">8</span><span class="border p-4">9</span>
  </section>
  <section class="d-flex">
    <span class="border position-sticky left-0 color-bg-subtle p-4">D</span>
    <span class="border p-4">1</span><span class="border p-4">2</span><span class="border p-4">3</span><span class="border p-4">4</span><span class="border p-4">5</span><span class="border p-4">6</span><span class="border p-4">7</span><span class="border p-4">8</span><span class="border p-4">9</span>
  </section>
  <section class="d-flex">
    <span class="border position-sticky left-0 color-bg-subtle p-4">E</span>
    <span class="border p-4">1</span><span class="border p-4">2</span><span class="border p-4">3</span><span class="border p-4">4</span><span class="border p-4">5</span><span class="border p-4">6</span><span class="border p-4">7</span><span class="border p-4">8</span><span class="border p-4">9</span>
    <span class="border position-sticky right-0 color-bg-subtle p-4">...</span>
  </section>
</div>

Responsive position

Position utilities can be applied or changed per breakpoint in responsive layouts. Each responsive position utility is applied to the specified breakpoint and up, using the following formula: position-[breakpoint]-[property]. For example: position-md-absolute.

<div style="height: 64px;">
  <div class="border position-md-absolute top-0 right-0">
    .position-md-absolute .top-0 .right-0
  </div>
</div>

Screen reader only

Use .sr-only to position an element outside of the viewport for screen reader access only. Even though the element can't be seen, make sure it still has a sensible tab order.

<div class="js-details-container Details">
  <button type="button" class="btn">Tab once from this button, and press enter</button>
  <button type="button" class="sr-only js-details-target">
    Screen reader only button
  </button>
  <div class="Details-content--hidden">
    Button activated!
  </div>
</div>

The media object

Create a media object with utilities.

<div class="clearfix p-3 border">
  <div class="float-left p-3 mr-3 color-bg-subtle">
    Image
  </div>
  <div class="overflow-hidden">
    <p><b>Body</b> Bacon ipsum dolor amet shankle rump tenderloin pork chop meatball strip steak bresaola doner sirloin capicola biltong shank pig. Alcatra frankfurter ham hock, ribeye prosciutto hamburger kevin brisket chuck burgdoggen short loin.</p>
  </div>
</div>

Create a double-sided media object for a container with a flexible center.

<div class="clearfix p-3 border">
  <div class="float-left p-3 mr-3 color-bg-subtle">
    Image
  </div>
  <div class="float-right p-3 ml-3 color-bg-subtle">
    Image
  </div>
  <div class="overflow-hidden">
    <p><b>Body</b> Bacon ipsum dolor amet shankle rump tenderloin pork chop meatball strip steak bresaola doner sirloin capicola biltong shank pig. Alcatra frankfurter ham hock, ribeye prosciutto hamburger kevin brisket chuck burgdoggen short loin.</p>
  </div>
</div>

You can also create a media object with flexbox utilities instead of floats which can be useful for changing the vertical alignment.