---
layout: page
title: Accessibility
---

Bootstrap follows common web standards and—with minimal extra effort—can be used to create sites that are accessible to those using <abbr title="Assistive Technology" class="initialism">AT</abbr>.

## Skip navigation

If your navigation contains many links and comes before the main content in the DOM, add a `Skip to main content` link before the navigation (for a simple explanation, see this [A11Y Project article on skip navigation links](http://a11yproject.com/posts/skip-nav-links/)). Using the `.sr-only` class will visually hide the skip link, and the <code>.sr-only-focusable</code> class will ensure that the link becomes visible once focused (for sighted keyboard users).

<div class="bd-callout bd-callout-danger" id="callout-skiplinks">
  <p>Due to long-standing shortcomings/bugs in Chrome (see <a href="https://code.google.com/p/chromium/issues/detail?id=262171" title="Chromium bug tracker - Issue 262171: Focus should cycle from named anchor">issue 262171 in the Chromium bug tracker</a>) and Internet Explorer (see this article on <a href="http://accessibleculture.org/articles/2010/05/in-page-links/">in-page links and focus order</a>), you will need to make sure that the target of your skip link is at least programmatically focusable by adding <code>tabindex="-1"</code>.</p>
  <p>In addition, you may want to explicitly suppress a visible focus indication on the target (particularly as Chrome currently also sets focus on elements with <code>tabindex="-1"</code> when they are clicked with the mouse) with <code>#content:focus { outline: none; }</code>.</p>
  <p>Note that this bug will also affect any other in-page links your site may be using, rendering them useless for keyboard users. You may consider adding a similar stop-gap fix to all other named anchors / fragment identifiers that act as link targets.</p>
</div>

{% highlight html %}
<body>
  <a href="#content" class="sr-only sr-only-focusable">Skip to main content</a>
  ...
  <div class="container" id="content" tabindex="-1">
    <!-- The main page content -->
  </div>
</body>
{% endhighlight %}

## Nested headings

When nesting headings (`<h1>` - `<h6>`), your primary document header should be an `<h1>`. Subsequent headings should make logical use of `<h2>` - `<h6>` such that screen readers can construct a table of contents for your pages.

Learn more at [HTML CodeSniffer](http://squizlabs.github.io/HTML_CodeSniffer/Standards/Section508/) and [Penn State's Accessability](http://accessibility.psu.edu/headings).

## Additional resources

- ["HTML Codesniffer" bookmarklet for identifying accessibility issues](https://github.com/squizlabs/HTML_CodeSniffer)
- [The A11Y Project](http://a11yproject.com/)
- [MDN accessibility documentation](https://developer.mozilla.org/en-US/docs/Accessibility)
