twbs--bootstrap/docs/getting-started/accessibility.md

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---
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
Merge branch 'master' into v4 Conflicts: .travis.yml Gruntfile.js bower.json dist/css/bootstrap.css dist/css/bootstrap.css.map dist/css/bootstrap.min.css dist/js/bootstrap.js dist/js/bootstrap.min.js docs/_data/glyphicons.yml docs/_includes/components/breadcrumbs.html docs/_includes/components/button-dropdowns.html docs/_includes/components/button-groups.html docs/_includes/components/dropdowns.html docs/_includes/components/glyphicons.html docs/_includes/components/labels.html docs/_includes/components/list-group.html docs/_includes/components/media.html docs/_includes/components/navs.html docs/_includes/components/panels.html docs/_includes/components/progress-bars.html docs/_includes/components/thumbnails.html docs/_includes/components/wells.html docs/_includes/css/buttons.html docs/_includes/css/forms.html docs/_includes/css/helpers.html docs/_includes/css/images.html docs/_includes/css/less.html docs/_includes/customizer-variables.html docs/_includes/getting-started/accessibility.html docs/_includes/getting-started/browser-device-support.html docs/_includes/getting-started/community.html docs/_includes/getting-started/examples.html docs/_includes/getting-started/grunt.html docs/_includes/getting-started/license.html docs/_includes/getting-started/template.html docs/_includes/header.html docs/_includes/js/affix.html docs/_includes/js/alerts.html docs/_includes/js/carousel.html docs/_includes/js/collapse.html docs/_includes/js/dropdowns.html docs/_includes/js/modal.html docs/_includes/js/overview.html docs/_includes/js/popovers.html docs/_includes/js/scrollspy.html docs/_includes/js/tabs.html docs/_includes/js/tooltips.html docs/_includes/js/transitions.html docs/_includes/nav/javascript.html docs/_layouts/default.html docs/assets/css/docs.min.css docs/assets/css/src/docs.css docs/assets/js/customize.min.js docs/assets/js/docs.min.js docs/assets/js/raw-files.min.js docs/assets/js/vendor/FileSaver.js docs/assets/js/vendor/autoprefixer.js docs/assets/js/vendor/uglify.min.js docs/dist/css/bootstrap.css docs/dist/css/bootstrap.css.map docs/dist/css/bootstrap.min.css docs/dist/js/bootstrap.min.js docs/examples/blog/index.html docs/examples/carousel/index.html docs/examples/cover/index.html docs/examples/dashboard/index.html docs/examples/narrow-jumbotron/narrow-jumbotron.css docs/examples/navbar-fixed-top/index.html docs/examples/navbar-static-top/index.html docs/examples/non-responsive/index.html docs/examples/non-responsive/non-responsive.css docs/examples/theme/index.html grunt/configBridge.json js/affix.js js/carousel.js js/collapse.js js/dropdown.js js/modal.js js/popover.js js/scrollspy.js js/tab.js js/tests/unit/affix.js js/tests/unit/button.js js/tests/unit/carousel.js js/tests/unit/modal.js js/tests/unit/tooltip.js js/tooltip.js less/badges.less less/glyphicons.less less/type.less less/variables.less package.json scss/_dropdown.scss scss/_forms.scss test-infra/npm-shrinkwrap.json
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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="bs-callout bs-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>
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{% highlight html %}
<body>
<a href="#content" class="sr-only sr-only-focusable">Skip to main content</a>
Merge branch 'master' into v4 Conflicts: .travis.yml Gruntfile.js bower.json dist/css/bootstrap.css dist/css/bootstrap.css.map dist/css/bootstrap.min.css dist/js/bootstrap.js dist/js/bootstrap.min.js docs/_data/glyphicons.yml docs/_includes/components/breadcrumbs.html docs/_includes/components/button-dropdowns.html docs/_includes/components/button-groups.html docs/_includes/components/dropdowns.html docs/_includes/components/glyphicons.html docs/_includes/components/labels.html docs/_includes/components/list-group.html docs/_includes/components/media.html docs/_includes/components/navs.html docs/_includes/components/panels.html docs/_includes/components/progress-bars.html docs/_includes/components/thumbnails.html docs/_includes/components/wells.html docs/_includes/css/buttons.html docs/_includes/css/forms.html docs/_includes/css/helpers.html docs/_includes/css/images.html docs/_includes/css/less.html docs/_includes/customizer-variables.html docs/_includes/getting-started/accessibility.html docs/_includes/getting-started/browser-device-support.html docs/_includes/getting-started/community.html docs/_includes/getting-started/examples.html docs/_includes/getting-started/grunt.html docs/_includes/getting-started/license.html docs/_includes/getting-started/template.html docs/_includes/header.html docs/_includes/js/affix.html docs/_includes/js/alerts.html docs/_includes/js/carousel.html docs/_includes/js/collapse.html docs/_includes/js/dropdowns.html docs/_includes/js/modal.html docs/_includes/js/overview.html docs/_includes/js/popovers.html docs/_includes/js/scrollspy.html docs/_includes/js/tabs.html docs/_includes/js/tooltips.html docs/_includes/js/transitions.html docs/_includes/nav/javascript.html docs/_layouts/default.html docs/assets/css/docs.min.css docs/assets/css/src/docs.css docs/assets/js/customize.min.js docs/assets/js/docs.min.js docs/assets/js/raw-files.min.js docs/assets/js/vendor/FileSaver.js docs/assets/js/vendor/autoprefixer.js docs/assets/js/vendor/uglify.min.js docs/dist/css/bootstrap.css docs/dist/css/bootstrap.css.map docs/dist/css/bootstrap.min.css docs/dist/js/bootstrap.min.js docs/examples/blog/index.html docs/examples/carousel/index.html docs/examples/cover/index.html docs/examples/dashboard/index.html docs/examples/narrow-jumbotron/narrow-jumbotron.css docs/examples/navbar-fixed-top/index.html docs/examples/navbar-static-top/index.html docs/examples/non-responsive/index.html docs/examples/non-responsive/non-responsive.css docs/examples/theme/index.html grunt/configBridge.json js/affix.js js/carousel.js js/collapse.js js/dropdown.js js/modal.js js/popover.js js/scrollspy.js js/tab.js js/tests/unit/affix.js js/tests/unit/button.js js/tests/unit/carousel.js js/tests/unit/modal.js js/tests/unit/tooltip.js js/tooltip.js less/badges.less less/glyphicons.less less/type.less less/variables.less package.json scss/_dropdown.scss scss/_forms.scss test-infra/npm-shrinkwrap.json
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...
<div class="container" id="content" tabindex="-1">
<!-- The main page content -->
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</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)