- title: Carousel
- title: Responsive embed
- title: Utilities
+ sections:
+ - title: Text alignment
+ - title: Text transform
+ - title: Contextual colors
+ - title: Contextual backgrounds
+ - title: Close icon
+ - title: Floats
+ - title: Center content
+ - title: Hidden content
+ - title: Invisible content
+ - title: Screen readers
+ - title: Image replacement
- title: Examples
pages:
title: Utility classes
---
+Bootstrap includes dozens of utilities—classes with a single purpose. They're designed to keep the number of declarations in your CSS down while allowing for quick and easy development.
+
+### Text alignment
+
+Easily realign text to components with text alignment classes.
+
+{% example html %}
+<p class="text-left">Left aligned text.</p>
+<p class="text-center">Center aligned text.</p>
+<p class="text-right">Right aligned text.</p>
+<p class="text-justify">Justified text.</p>
+<p class="text-nowrap">No wrap text.</p>
+{% endexample %}
+
+### Text transform
+
+Transform text in components with text capitalization classes.
+
+{% example html %}
+<p class="text-lowercase">Lowercased text.</p>
+<p class="text-uppercase">Uppercased text.</p>
+<p class="text-capitalize">Capitalized text.</p>
+{% endexample %}
+
### Contextual colors
Convey meaning through color with a handful of emphasis utility classes. These may also be applied to links and will darken on hover just like our default link styles.
</button>
{% endexample %}
-### Quick floats
+### Floats
Float an element to the left or right with a class. `!important` is included to avoid specificity issues. Classes can also be used as mixins.
}
{% endhighlight %}
-### Center content blocks
+### Center content
Set an element to `display: block;` and center via `margin`. Available as a mixin and class.
}
{% endhighlight %}
-### Screen readers and keyboard navigation
+### Screen readers
Hide an element to all devices **except screen readers** with `.sr-only`. Combine `.sr-only` with `.sr-only-focusable` to show the element again when it's focused (e.g. by a keyboard-only user). Necessary for following [accessibility best practices](../getting-started/#accessibility). Can also be used as mixins.
While not shown above, feel free to use `<b>` and `<i>` in HTML5. `<b>` is meant to highlight words or phrases without conveying additional importance while `<i>` is mostly for voice, technical terms, etc.
-## Alignment classes
-
-Easily realign text to components with text alignment classes.
-
-{% example html %}
-<p class="text-left">Left aligned text.</p>
-<p class="text-center">Center aligned text.</p>
-<p class="text-right">Right aligned text.</p>
-<p class="text-justify">Justified text.</p>
-<p class="text-nowrap">No wrap text.</p>
-{% endexample %}
-
-## Transformation classes
-
-Transform text in components with text capitalization classes.
-
-{% example html %}
-<p class="text-lowercase">Lowercased text.</p>
-<p class="text-uppercase">Uppercased text.</p>
-<p class="text-capitalize">Capitalized text.</p>
-{% endexample %}
-
## Abbreviations
Stylized implementation of HTML's `<abbr>` element for abbreviations and acronyms to show the expanded version on hover. Abbreviations with a `title` attribute have a light dotted bottom border and a help cursor on hover, providing additional context on hover and to users of assistive technologies.