Overview
Get the lowdown on the key pieces of Bootstrap’s infrastructure, including our approach to better, faster, stronger web development.
HTML5 doctype
Bootstrap makes use of certain HTML elements and CSS properties that require the use of the HTML5 doctype. Include it at the beginning of all your projects.
<!DOCTYPE html>
<html lang="en">
...
</html>Mobile first
With Bootstrap 2, we added optional mobile friendly styles for key aspects of the framework. With Bootstrap 3, we’ve rewritten the project to be mobile friendly from the start. Instead of adding on optional mobile styles, they’re baked right into the core. In fact, Bootstrap is mobile first. Mobile first styles can be found throughout the entire library instead of in separate files.
To ensure proper rendering and touch zooming, add the viewport meta tag to your <head>.
<meta name="viewport" content="width=device-width, initial-scale=1">You can disable zooming capabilities on mobile devices by adding user-scalable=no to the viewport meta tag. This disables zooming, meaning users are only able to scroll, and results in your site feeling a bit more like a native application. Overall, we don’t recommend this on every site, so use caution!
<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no">Typography and links
Bootstrap sets basic global display, typography, and link styles. Specifically, we:
- Set
background-color: #fff;on thebody - Use the
@font-family-base,@font-size-base, and@line-height-baseattributes as our typographic base - Set the global link color via
@link-colorand apply link underlines only on:hover
These styles can be found within scaffolding.less.
Normalize.css
For improved cross-browser rendering, we use Normalize.css, a project by Nicolas Gallagher and Jonathan Neal.
Containers
Easily center a page’s contents by wrapping its contents in a .container. Containers set width at various media query breakpoints to match our grid system.
Note that, due to padding and fixed widths, containers are not nestable by default.
<div class="container">
...
</div>Grid system
Bootstrap includes a responsive, mobile first fluid grid system that appropriately scales up to 12 columns as the device or viewport size increases. It includes predefined classes for easy layout options, as well as powerful mixins for generating more semantic layouts.
Introduction
Grid systems are used for creating page layouts through a series of rows and columns that house your content. Here’s how the Bootstrap grid system works:
- Rows must be placed within a
.container(fixed-width) or.container-fluid(full-width) for proper alignment and padding. - Use rows to create horizontal groups of columns.
- Content should be placed within columns, and only columns may be immediate children of rows.
- Predefined grid classes like
.rowand.col-xs-4are available for quickly making grid layouts. Less mixins can also be used for more semantic layouts. - Columns create gutters (gaps between column content) via
padding. That padding is offset in rows for the first and last column via negative margin on.rows. - Grid columns are created by specifying the number of twelve available columns you wish to span. For example, three equal columns would use three
.col-xs-4.
Look to the examples for applying these principles to your code.
Media queries
We use the following media queries in our Less files to create the key breakpoints in our grid system.
/* Extra small devices (phones, less than 768px) */
/* No media query since this is the default in Bootstrap */
/* Small devices (tablets, 768px and up) */
@media (min-width: @screen-sm-min) { ... }
/* Medium devices (desktops, 992px and up) */
@media (min-width: @screen-md-min) { ... }
/* Large devices (large desktops, 1200px and up) */
@media (min-width: @screen-lg-min) { ... }We occasionally expand on these media queries to include a max-width to limit CSS to a narrower set of devices.
@media (max-width: @screen-xs-max) { ... }
@media (min-width: @screen-sm-min) and (max-width: @screen-sm-max) { ... }
@media (min-width: @screen-md-min) and (max-width: @screen-md-max) { ... }
@media (min-width: @screen-lg-min) { ... }Grid options
See how aspects of the Bootstrap grid system work across multiple devices with a handy table.
| Extra small devices Phones (<768px) | Small devices Tablets (≥768px) | Medium devices Desktops (≥992px) | Large devices Desktops (≥1200px) | |
|---|---|---|---|---|
| Grid behavior | Horizontal at all times | Collapsed to start, horizontal above breakpoints | ||
| Container width | None (auto) | 750px | 970px | 1170px |
| Class prefix | .col-xs- |
.col-sm- |
.col-md- |
.col-lg- |
| # of columns | 12 | |||
| Column width | Auto | 60px | 78px | 95px |
| Gutter width | 30px (15px on each side of a column) | |||
| Nestable | Yes | |||
| Offsets | Yes | |||
| Column ordering | Yes | |||
Grid classes apply to devices with screen widths greater than or equal to the breakpoint sizes, and override grid classes targeted at smaller devices. Therefore, applying any .col-md- class to an element will not only affect its styling on medium devices but also on large devices if a .col-lg- class is not present.
Example: Stacked-to-horizontal
Using a single set of .col-md-* grid classes, you can create a basic grid system that starts out stacked on mobile devices and tablet devices (the extra small to small range) before becoming horizontal on desktop (medium) devices. Place grid columns in any .row.
<div class="row">
<div class="col-md-1">.col-md-1</div>
<div class="col-md-1">.col-md-1</div>
<div class="col-md-1">.col-md-1</div>
<div class="col-md-1">.col-md-1</div>
<div class="col-md-1">.col-md-1</div>
<div class="col-md-1">.col-md-1</div>
<div class="col-md-1">.col-md-1</div>
<div class="col-md-1">.col-md-1</div>
<div class="col-md-1">.col-md-1</div>
<div class="col-md-1">.col-md-1</div>
<div class="col-md-1">.col-md-1</div>
<div class="col-md-1">.col-md-1</div>
</div>
<div class="row">
<div class="col-md-8">.col-md-8</div>
<div class="col-md-4">.col-md-4</div>
</div>
<div class="row">
<div class="col-md-4">.col-md-4</div>
<div class="col-md-4">.col-md-4</div>
<div class="col-md-4">.col-md-4</div>
</div>
<div class="row">
<div class="col-md-6">.col-md-6</div>
<div class="col-md-6">.col-md-6</div>
</div>Example: Fluid container
Turn any fixed-width grid layout into a full-width layout by changing your outermost .container to .container-fluid.
<div class="container-fluid">
<div class="row">
...
</div>
</div>Example: Mobile and desktop
Don’t want your columns to simply stack in smaller devices? Use the extra small and medium device grid classes by adding .col-xs-* .col-md-* to your columns. See the example below for a better idea of how it all works.
<!-- Stack the columns on mobile by making one full-width and the other half-width -->
<div class="row">
<div class="col-xs-12 col-md-8">.col-xs-12 .col-md-8</div>
<div class="col-xs-6 col-md-4">.col-xs-6 .col-md-4</div>
</div>
<!-- Columns start at 50% wide on mobile and bump up to 33.3% wide on desktop -->
<div class="row">
<div class="col-xs-6 col-md-4">.col-xs-6 .col-md-4</div>
<div class="col-xs-6 col-md-4">.col-xs-6 .col-md-4</div>
<div class="col-xs-6 col-md-4">.col-xs-6 .col-md-4</div>
</div>
<!-- Columns are always 50% wide, on mobile and desktop -->
<div class="row">
<div class="col-xs-6">.col-xs-6</div>
<div class="col-xs-6">.col-xs-6</div>
</div>Example: Mobile, tablet, desktops
Build on the previous example by creating even more dynamic and powerful layouts with tablet .col-sm-* classes.
<div class="row">
<div class="col-xs-12 col-sm-6 col-md-8">.col-xs-12 .col-sm-6 .col-md-8</div>
<div class="col-xs-6 col-md-4">.col-xs-6 .col-md-4</div>
</div>
<div class="row">
<div class="col-xs-6 col-sm-4">.col-xs-6 .col-sm-4</div>
<div class="col-xs-6 col-sm-4">.col-xs-6 .col-sm-4</div>
<!-- Optional: clear the XS cols if their content doesn't match in height -->
<div class="clearfix visible-xs"></div>
<div class="col-xs-6 col-sm-4">.col-xs-6 .col-sm-4</div>
</div>Responsive column resets
With the four tiers of grids available you’re bound to run into issues where, at certain breakpoints, your columns don’t clear quite right as one is taller than the other. To fix that, use a combination of a .clearfix and our responsive utility classes.
Resize your viewport or check it out on your phone for an example.
<div class="row">
<div class="col-xs-6 col-sm-3">.col-xs-6 .col-sm-3</div>
<div class="col-xs-6 col-sm-3">.col-xs-6 .col-sm-3</div>
<!-- Add the extra clearfix for only the required viewport -->
<div class="clearfix visible-xs"></div>
<div class="col-xs-6 col-sm-3">.col-xs-6 .col-sm-3</div>
<div class="col-xs-6 col-sm-3">.col-xs-6 .col-sm-3</div>
</div>In addition to column clearing at responsive breakpoints, you may need to reset offsets, pushes, or pulls. See this in action in the grid example.
<div class="row">
<div class="col-sm-5 col-md-6">.col-sm-5 .col-md-6</div>
<div class="col-sm-5 col-sm-offset-2 col-md-6 col-md-offset-0">.col-sm-5 .col-sm-offset-2 .col-md-6 .col-md-offset-0</div>
</div>
<div class="row">
<div class="col-sm-6 col-md-5 col-lg-6">.col-sm-6 .col-md-5 .col-lg-6</div>
<div class="col-sm-6 col-md-5 col-md-offset-2 col-lg-6 col-lg-offset-0">.col-sm-6 .col-md-5 .col-md-offset-2 .col-lg-6 .col-lg-offset-0</div>
</div>Offsetting columns
Move columns to the right using .col-md-offset-* classes. These classes increase the left margin of a column by * columns. For example, .col-md-offset-4 moves .col-md-4 over four columns.
<div class="row">
<div class="col-md-4">.col-md-4</div>
<div class="col-md-4 col-md-offset-4">.col-md-4 .col-md-offset-4</div>
</div>
<div class="row">
<div class="col-md-3 col-md-offset-3">.col-md-3 .col-md-offset-3</div>
<div class="col-md-3 col-md-offset-3">.col-md-3 .col-md-offset-3</div>
</div>
<div class="row">
<div class="col-md-6 col-md-offset-3">.col-md-6 .col-md-offset-3</div>
</div>Nesting columns
To nest your content with the default grid, add a new .row and set of .col-md-* columns within an existing .col-md-* column. Nested rows should include a set of columns that add up to 12 or less.
<div class="row">
<div class="col-md-9">
Level 1: .col-md-9
<div class="row">
<div class="col-md-6">
Level 2: .col-md-6
</div>
<div class="col-md-6">
Level 2: .col-md-6
</div>
</div>
</div>
</div>Column ordering
Easily change the order of our built-in grid columns with .col-md-push-* and .col-md-pull-* modifier classes.
<div class="row">
<div class="col-md-9 col-md-push-3">.col-md-9 .col-md-push-3</div>
<div class="col-md-3 col-md-pull-9">.col-md-3 .col-md-pull-9</div>
</div>Less mixins and variables
In addition to prebuilt grid classes for fast layouts, Bootstrap includes Less variables and mixins for quickly generating your own simple, semantic layouts.
Variables
Variables determine the number of columns, the gutter width, and the media query point at which to begin floating columns. We use these to generate the predefined grid classes documented above, as well as for the custom mixins listed below.
@grid-columns: 12;
@grid-gutter-width: 30px;
@grid-float-breakpoint: 768px;Mixins
Mixins are used in conjunction with the grid variables to generate semantic CSS for individual grid columns.
// Creates a wrapper for a series of columns
.make-row(@gutter: @grid-gutter-width) {
// Then clear the floated columns
.clearfix();
@media (min-width: @screen-sm-min) {
margin-left: (@gutter / -2);
margin-right: (@gutter / -2);
}
// Negative margin nested rows out to align the content of columns
.row {
margin-left: (@gutter / -2);
margin-right: (@gutter / -2);
}
}
// Generate the extra small columns
.make-xs-column(@columns; @gutter: @grid-gutter-width) {
position: relative;
// Prevent columns from collapsing when empty
min-height: 1px;
// Inner gutter via padding
padding-left: (@gutter / 2);
padding-right: (@gutter / 2);
// Calculate width based on number of columns available
@media (min-width: @grid-float-breakpoint) {
float: left;
width: percentage((@columns / @grid-columns));
}
}
// Generate the small columns
.make-sm-column(@columns; @gutter: @grid-gutter-width) {
position: relative;
// Prevent columns from collapsing when empty
min-height: 1px;
// Inner gutter via padding
padding-left: (@gutter / 2);
padding-right: (@gutter / 2);
// Calculate width based on number of columns available
@media (min-width: @screen-sm-min) {
float: left;
width: percentage((@columns / @grid-columns));
}
}
// Generate the small column offsets
.make-sm-column-offset(@columns) {
@media (min-width: @screen-sm-min) {
margin-left: percentage((@columns / @grid-columns));
}
}
.make-sm-column-push(@columns) {
@media (min-width: @screen-sm-min) {
left: percentage((@columns / @grid-columns));
}
}
.make-sm-column-pull(@columns) {
@media (min-width: @screen-sm-min) {
right: percentage((@columns / @grid-columns));
}
}
// Generate the medium columns
.make-md-column(@columns; @gutter: @grid-gutter-width) {
position: relative;
// Prevent columns from collapsing when empty
min-height: 1px;
// Inner gutter via padding
padding-left: (@gutter / 2);
padding-right: (@gutter / 2);
// Calculate width based on number of columns available
@media (min-width: @screen-md-min) {
float: left;
width: percentage((@columns / @grid-columns));
}
}
// Generate the medium column offsets
.make-md-column-offset(@columns) {
@media (min-width: @screen-md-min) {
margin-left: percentage((@columns / @grid-columns));
}
}
.make-md-column-push(@columns) {
@media (min-width: @screen-md-min) {
left: percentage((@columns / @grid-columns));
}
}
.make-md-column-pull(@columns) {
@media (min-width: @screen-md-min) {
right: percentage((@columns / @grid-columns));
}
}
// Generate the large columns
.make-lg-column(@columns; @gutter: @grid-gutter-width) {
position: relative;
// Prevent columns from collapsing when empty
min-height: 1px;
// Inner gutter via padding
padding-left: (@gutter / 2);
padding-right: (@gutter / 2);
// Calculate width based on number of columns available
@media (min-width: @screen-lg-min) {
float: left;
width: percentage((@columns / @grid-columns));
}
}
// Generate the large column offsets
.make-lg-column-offset(@columns) {
@media (min-width: @screen-lg-min) {
margin-left: percentage((@columns / @grid-columns));
}
}
.make-lg-column-push(@columns) {
@media (min-width: @screen-lg-min) {
left: percentage((@columns / @grid-columns));
}
}
.make-lg-column-pull(@columns) {
@media (min-width: @screen-lg-min) {
right: percentage((@columns / @grid-columns));
}
}Example usage
You can modify the variables to your own custom values, or just use the mixins with their default values. Here’s an example of using the default settings to create a two-column layout with a gap between.
.wrapper {
.make-row();
}
.content-main {
.make-lg-column(8);
}
.content-secondary {
.make-lg-column(3);
.make-lg-column-offset(1);
}<div class="wrapper">
<div class="content-main">...</div>
<div class="content-secondary">...</div>
</div>Typography
Headings
All HTML headings, <h1> through <h6>, are available. .h1 through .h6 classes are also available, for when you want to match the font styling of a heading but still want your text to be displayed inline.
h1. Bootstrap heading |
Semibold 36px |
h2. Bootstrap heading |
Semibold 30px |
h3. Bootstrap heading |
Semibold 24px |
h4. Bootstrap heading |
Semibold 18px |
h5. Bootstrap heading |
Semibold 14px |
h6. Bootstrap heading |
Semibold 12px |
<h1>h1. Bootstrap heading</h1>
<h2>h2. Bootstrap heading</h2>
<h3>h3. Bootstrap heading</h3>
<h4>h4. Bootstrap heading</h4>
<h5>h5. Bootstrap heading</h5>
<h6>h6. Bootstrap heading</h6>Create lighter, secondary text in any heading with a generic <small> tag or the .small class.
h1. Bootstrap heading Secondary text |
h2. Bootstrap heading Secondary text |
h3. Bootstrap heading Secondary text |
h4. Bootstrap heading Secondary text |
h5. Bootstrap heading Secondary text |
h6. Bootstrap heading Secondary text |
<h1>h1. Bootstrap heading <small>Secondary text</small></h1>
<h2>h2. Bootstrap heading <small>Secondary text</small></h2>
<h3>h3. Bootstrap heading <small>Secondary text</small></h3>
<h4>h4. Bootstrap heading <small>Secondary text</small></h4>
<h5>h5. Bootstrap heading <small>Secondary text</small></h5>
<h6>h6. Bootstrap heading <small>Secondary text</small></h6>Body copy
Bootstrap’s global default font-size is 14px, with a line-height of 1.428. This is applied to the <body> and all paragraphs. In addition, <p> (paragraphs) receive a bottom margin of half their computed line-height (10px by default).
Nullam quis risus eget urna mollis ornare vel eu leo. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Nullam id dolor id nibh ultricies vehicula.
Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Donec ullamcorper nulla non metus auctor fringilla. Duis mollis, est non commodo luctus, nisi erat porttitor ligula, eget lacinia odio sem nec elit. Donec ullamcorper nulla non metus auctor fringilla.
Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Duis mollis, est non commodo luctus, nisi erat porttitor ligula, eget lacinia odio sem nec elit.
<p>...</p>Lead body copy
Make a paragraph stand out by adding .lead.
Vivamus sagittis lacus vel augue laoreet rutrum faucibus dolor auctor. Duis mollis, est non commodo luctus.
<p class="lead">...</p>Built with Less
The typographic scale is based on two Less variables in variables.less: @font-size-base and @line-height-base. The first is the base font-size used throughout and the second is the base line-height. We use those variables and some simple math to create the margins, paddings, and line-heights of all our type and more. Customize them and Bootstrap adapts.
Emphasis
Make use of HTML’s default emphasis tags with lightweight styles.
Small text
For de-emphasizing inline or blocks of text, use the <small> tag to set text at 85% the size of the parent. Heading elements receive their own font-size for nested <small> elements.
You may alternatively use an inline element with .small in place of any <small>.
This line of text is meant to be treated as fine print.
<small>This line of text is meant to be treated as fine print.</small>Bold
For emphasizing a snippet of text with a heavier font-weight.
The following snippet of text is rendered as bold text.
<strong>rendered as bold text</strong>Italics
For emphasizing a snippet of text with italics.
The following snippet of text is rendered as italicized text.
<em>rendered as italicized text</em>Alternate elements
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.
Left aligned text.
Center aligned text.
Right aligned text.
Justified text.
<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>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.
Basic abbreviation
For expanded text on long hover of an abbreviation, include the title attribute with the <abbr> element.
An abbreviation of the word attribute is attr.
<abbr title="attribute">attr</abbr>Initialism
Add .initialism to an abbreviation for a slightly smaller font-size.
HTML is the best thing since sliced bread.
<abbr title="HyperText Markup Language" class="initialism">HTML</abbr>Addresses
Present contact information for the nearest ancestor or the entire body of work. Preserve formatting by ending all lines with <br>.
795 Folsom Ave, Suite 600
San Francisco, CA 94107
P: (123) 456-7890 Full Name
first.last@example.com
<address>
<strong>Twitter, Inc.</strong><br>
795 Folsom Ave, Suite 600<br>
San Francisco, CA 94107<br>
<abbr title="Phone">P:</abbr> (123) 456-7890
</address>
<address>
<strong>Full Name</strong><br>
<a href="mailto:#">first.last@example.com</a>
</address>Blockquotes
For quoting blocks of content from another source within your document.
Default blockquote
Wrap <blockquote> around any HTML as the quote. For straight quotes, we recommend a <p>.
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.
<blockquote>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>
</blockquote>Blockquote options
Style and content changes for simple variations on a standard <blockquote>.
Naming a source
Add a <footer> for identifying the source. Wrap the name of the source work in <cite>.
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.
<blockquote>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>
<footer>Someone famous in <cite title="Source Title">Source Title</cite></footer>
</blockquote>Alternate displays
Add .blockquote-reverse for a blockquote with right-aligned content.
<blockquote class="blockquote-reverse">
...
</blockquote>Lists
Unordered
A list of items in which the order does not explicitly matter.
- Lorem ipsum dolor sit amet
- Consectetur adipiscing elit
- Integer molestie lorem at massa
- Facilisis in pretium nisl aliquet
- Nulla volutpat aliquam velit
- Phasellus iaculis neque
- Purus sodales ultricies
- Vestibulum laoreet porttitor sem
- Ac tristique libero volutpat at
- Faucibus porta lacus fringilla vel
- Aenean sit amet erat nunc
- Eget porttitor lorem
<ul>
<li>...</li>
</ul>Ordered
A list of items in which the order does explicitly matter.
- Lorem ipsum dolor sit amet
- Consectetur adipiscing elit
- Integer molestie lorem at massa
- Facilisis in pretium nisl aliquet
- Nulla volutpat aliquam velit
- Faucibus porta lacus fringilla vel
- Aenean sit amet erat nunc
- Eget porttitor lorem
<ol>
<li>...</li>
</ol>Unstyled
Remove the default list-style and left margin on list items (immediate children only). This only applies to immediate children list items, meaning you will need to add the class for any nested lists as well.
- Lorem ipsum dolor sit amet
- Consectetur adipiscing elit
- Integer molestie lorem at massa
- Facilisis in pretium nisl aliquet
- Nulla volutpat aliquam velit
- Phasellus iaculis neque
- Purus sodales ultricies
- Vestibulum laoreet porttitor sem
- Ac tristique libero volutpat at
- Faucibus porta lacus fringilla vel
- Aenean sit amet erat nunc
- Eget porttitor lorem
<ul class="list-unstyled">
<li>...</li>
</ul>Inline
Place all list items on a single line with display: inline-block; and some light padding.
- Lorem ipsum
- Phasellus iaculis
- Nulla volutpat
<ul class="list-inline">
<li>...</li>
</ul>Description
A list of terms with their associated descriptions.
- Description lists
- A description list is perfect for defining terms.
- Euismod
- Vestibulum id ligula porta felis euismod semper eget lacinia odio sem nec elit.
- Donec id elit non mi porta gravida at eget metus.
- Malesuada porta
- Etiam porta sem malesuada magna mollis euismod.
<dl>
<dt>...</dt>
<dd>...</dd>
</dl>Horizontal description
Make terms and descriptions in <dl> line up side-by-side. Starts off stacked like default <dl>s, but when the navbar expands, so do these.
- Description lists
- A description list is perfect for defining terms.
- Euismod
- Vestibulum id ligula porta felis euismod semper eget lacinia odio sem nec elit.
- Donec id elit non mi porta gravida at eget metus.
- Malesuada porta
- Etiam porta sem malesuada magna mollis euismod.
- Felis euismod semper eget lacinia
- Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus.
<dl class="dl-horizontal">
<dt>...</dt>
<dd>...</dd>
</dl>Auto-truncating
Horizontal description lists will truncate terms that are too long to fit in the left column with text-overflow. In narrower viewports, they will change to the default stacked layout.
Code
Inline
Wrap inline snippets of code with <code>.
<section> should be wrapped as inline.
For example, <code><section></code> should be wrapped as inline.User input
Use the <kbd> to indicate input that is typically entered via keyboard.
To switch directories, type <kbd>cd</kbd> followed by the name of the directory.Basic block
Use <pre> for multiple lines of code. Be sure to escape any angle brackets in the code for proper rendering.
<p>Sample text here...</p>
<pre><p>Sample text here...</p></pre>You may optionally add the .pre-scrollable class, which will set a max-height of 350px and provide a y-axis scrollbar.
Tables
Basic example
For basic styling—light padding and only horizontal dividers—add the base class .table to any <table>. It may seem super redundant, but given the widespread use of tables for other plugins like calendars and date pickers, we’ve opted to isolate our custom table styles.
| # | First Name | Last Name | Username |
|---|---|---|---|
| 1 | Mark | Otto | @mdo |
| 2 | Jacob | Thornton | @fat |
| 3 | Larry | the Bird |
<table class="table">
...
</table>Striped rows
Use .table-striped to add zebra-striping to any table row within the <tbody>.
Cross-browser compatibility
Striped tables are styled via the :nth-child CSS selector, which is not available in Internet Explorer 8.
| # | First Name | Last Name | Username |
|---|---|---|---|
| 1 | Mark | Otto | @mdo |
| 2 | Jacob | Thornton | @fat |
| 3 | Larry | the Bird |
<table class="table table-striped">
...
</table>Bordered table
Add .table-bordered for borders on all sides of the table and cells.
| # | First Name | Last Name | Username |
|---|---|---|---|
| 1 | Mark | Otto | @mdo |
| Mark | Otto | @TwBootstrap | |
| 2 | Jacob | Thornton | @fat |
| 3 | Larry the Bird | ||
<table class="table table-bordered">
...
</table>Hover rows
Add .table-hover to enable a hover state on table rows within a <tbody>.
| # | First Name | Last Name | Username |
|---|---|---|---|
| 1 | Mark | Otto | @mdo |
| 2 | Jacob | Thornton | @fat |
| 3 | Larry the Bird | ||
<table class="table table-hover">
...
</table>Condensed table
Add .table-condensed to make tables more compact by cutting cell padding in half.
| # | First Name | Last Name | Username |
|---|---|---|---|
| 1 | Mark | Otto | @mdo |
| 2 | Jacob | Thornton | @fat |
| 3 | Larry the Bird | ||
<table class="table table-condensed">
...
</table>Contextual classes
Use contextual classes to color table rows or individual cells.
| Class | Description |
|---|---|
.active
|
Applies the hover color to a particular row or cell |
.success
|
Indicates a successful or positive action |
.info
|
Indicates a neutral informative change or action |
.warning
|
Indicates a warning that might need attention |
.danger
|
Indicates a dangerous or potentially negative action |
| # | Column heading | Column heading | Column heading |
|---|---|---|---|
| 1 | Column content | Column content | Column content |
| 2 | Column content | Column content | Column content |
| 3 | Column content | Column content | Column content |
| 4 | Column content | Column content | Column content |
| 5 | Column content | Column content | Column content |
| 6 | Column content | Column content | Column content |
| 7 | Column content | Column content | Column content |
| 8 | Column content | Column content | Column content |
| 9 | Column content | Column content | Column content |
<!-- On rows -->
<tr class="active">...</tr>
<tr class="success">...</tr>
<tr class="warning">...</tr>
<tr class="danger">...</tr>
<tr class="info">...</tr>
<!-- On cells (`td` or `th`) -->
<tr>
<td class="active">...</td>
<td class="success">...</td>
<td class="warning">...</td>
<td class="danger">...</td>
<td class="info">...</td>
</tr>Responsive tables
Create responsive tables by wrapping any .table in .table-responsive to make them scroll horizontally up to small devices (under 768px). When viewing on anything larger than 768px wide, you will not see any difference in these tables.
| # | Table heading | Table heading | Table heading | Table heading | Table heading | Table heading |
|---|---|---|---|---|---|---|
| 1 | Table cell | Table cell | Table cell | Table cell | Table cell | Table cell |
| 2 | Table cell | Table cell | Table cell | Table cell | Table cell | Table cell |
| 3 | Table cell | Table cell | Table cell | Table cell | Table cell | Table cell |
| # | Table heading | Table heading | Table heading | Table heading | Table heading | Table heading |
|---|---|---|---|---|---|---|
| 1 | Table cell | Table cell | Table cell | Table cell | Table cell | Table cell |
| 2 | Table cell | Table cell | Table cell | Table cell | Table cell | Table cell |
| 3 | Table cell | Table cell | Table cell | Table cell | Table cell | Table cell |
<div class="table-responsive">
<table class="table">
...
</table>
</div>Forms
Basic example
Individual form controls automatically receive some global styling. All textual <input>, <textarea>, and <select> elements with .form-control are set to width: 100%; by default. Wrap labels and controls in .form-group for optimum spacing.
<form role="form">
<div class="form-group">
<label for="exampleInputEmail1">Email address</label>
<input type="email" class="form-control" id="exampleInputEmail1" placeholder="Enter email">
</div>
<div class="form-group">
<label for="exampleInputPassword1">Password</label>
<input type="password" class="form-control" id="exampleInputPassword1" placeholder="Password">
</div>
<div class="form-group">
<label for="exampleInputFile">File input</label>
<input type="file" id="exampleInputFile">
<p class="help-block">Example block-level help text here.</p>
</div>
<div class="checkbox">
<label>
<input type="checkbox"> Check me out
</label>
</div>
<button type="submit" class="btn btn-default">Submit</button>
</form>Don’t mix form groups with input groups
Do not mix form groups directly with input groups. Instead, nest the input group inside of the form group.
Inline form
Add .form-inline to your <form> for left-aligned and inline-block controls. This only applies to forms within viewports that are at least 768px wide.
Requires custom widths
Inputs, selects, and textareas are 100% wide by default in Bootstrap. To use the inline form, you’ll have to set a width on the form controls used within.
Always add labels
Screen readers will have trouble with your forms if you don’t include a label for every input. For these inline forms, you can hide the labels using the .sr-only class.
<form class="form-inline" role="form">
<div class="form-group">
<label class="sr-only" for="exampleInputEmail2">Email address</label>
<input type="email" class="form-control" id="exampleInputEmail2" placeholder="Enter email">
</div>
<div class="form-group">
<label class="sr-only" for="exampleInputPassword2">Password</label>
<input type="password" class="form-control" id="exampleInputPassword2" placeholder="Password">
</div>
<div class="checkbox">
<label>
<input type="checkbox"> Remember me
</label>
</div>
<button type="submit" class="btn btn-default">Sign in</button>
</form>Horizontal form
Use Bootstrap’s predefined grid classes to align labels and groups of form controls in a horizontal layout by adding .form-horizontal to the form. Doing so changes .form-groups to behave as grid rows, so no need for .row.
<form class="form-horizontal" role="form">
<div class="form-group">
<label for="inputEmail3" class="col-sm-2 control-label">Email</label>
<div class="col-sm-10">
<input type="email" class="form-control" id="inputEmail3" placeholder="Email">
</div>
</div>
<div class="form-group">
<label for="inputPassword3" class="col-sm-2 control-label">Password</label>
<div class="col-sm-10">
<input type="password" class="form-control" id="inputPassword3" placeholder="Password">
</div>
</div>
<div class="form-group">
<div class="col-sm-offset-2 col-sm-10">
<div class="checkbox">
<label>
<input type="checkbox"> Remember me
</label>
</div>
</div>
</div>
<div class="form-group">
<div class="col-sm-offset-2 col-sm-10">
<button type="submit" class="btn btn-default">Sign in</button>
</div>
</div>
</form>Supported controls
Examples of standard form controls supported in an example form layout.
Inputs
Most common form control, text-based input fields. Includes support for all HTML5 types: text, password, datetime, datetime-local, date, month, time, week, number, email, url, search, tel, and color.
Type declaration required
Inputs will only be fully styled if their type is properly declared.
<input type="text" class="form-control" placeholder="Text input">Input groups
To add integrated text or buttons before and/or after any text-based <input>, check out the input group component.
Textarea
Form control which supports multiple lines of text. Change rows attribute as necessary.
<textarea class="form-control" rows="3"></textarea>Checkboxes and radios
Checkboxes are for selecting one or several options in a list while radios are for selecting one option from many.
Default (stacked)
<div class="checkbox">
<label>
<input type="checkbox" value="">
Option one is this and that—be sure to include why it's great
</label>
</div>
<div class="radio">
<label>
<input type="radio" name="optionsRadios" id="optionsRadios1" value="option1" checked>
Option one is this and that—be sure to include why it's great
</label>
</div>
<div class="radio">
<label>
<input type="radio" name="optionsRadios" id="optionsRadios2" value="option2">
Option two can be something else and selecting it will deselect option one
</label>
</div>Inline checkboxes
Use the .checkbox-inline or .radio-inline classes on a series of checkboxes or radios for controls that appear on the same line.
<label class="checkbox-inline">
<input type="checkbox" id="inlineCheckbox1" value="option1"> 1
</label>
<label class="checkbox-inline">
<input type="checkbox" id="inlineCheckbox2" value="option2"> 2
</label>
<label class="checkbox-inline">
<input type="checkbox" id="inlineCheckbox3" value="option3"> 3
</label>Selects
Use the default option, or add multiple to show multiple options at once.
<select class="form-control">
<option>1</option>
<option>2</option>
<option>3</option>
<option>4</option>
<option>5</option>
</select>
<select multiple class="form-control">
<option>1</option>
<option>2</option>
<option>3</option>
<option>4</option>
<option>5</option>
</select>Static control
When you need to place plain text next to a form label within a horizontal form, use the .form-control-static class on a <p>.
<form class="form-horizontal" role="form">
<div class="form-group">
<label class="col-sm-2 control-label">Email</label>
<div class="col-sm-10">
<p class="form-control-static">email@example.com</p>
</div>
</div>
<div class="form-group">
<label for="inputPassword" class="col-sm-2 control-label">Password</label>
<div class="col-sm-10">
<input type="password" class="form-control" id="inputPassword" placeholder="Password">
</div>
</div>
</form>Input focus
We remove the default outline styles on some form controls and apply a box-shadow in its place for :focus.
Demo :focus state
The above example input uses custom styles in our documentation to demonstrate the :focus state on a .form-control.
Disabled inputs
Add the disabled attribute on an input to prevent user input and trigger a slightly different look.
<input class="form-control" id="disabledInput" type="text" placeholder="Disabled input here..." disabled>Disabled fieldsets
Add the disabled attribute to a <fieldset> to disable all the controls within the <fieldset> at once.
Link functionality of <a> not impacted
This class will only change the appearance of <a class="btn btn-default"> buttons, not their functionality. Use custom JavaScript to disable links here.
Cross-browser compatibility
While Bootstrap will apply these styles in all browsers, Internet Explorer 9 and below don’t actually support the disabled attribute on a <fieldset>. Use custom JavaScript to disable the fieldset in these browsers.
<form role="form">
<fieldset disabled>
<div class="form-group">
<label for="disabledTextInput">Disabled input</label>
<input type="text" id="disabledTextInput" class="form-control" placeholder="Disabled input">
</div>
<div class="form-group">
<label for="disabledSelect">Disabled select menu</label>
<select id="disabledSelect" class="form-control">
<option>Disabled select</option>
</select>
</div>
<div class="checkbox">
<label>
<input type="checkbox"> Can't check this
</label>
</div>
<button type="submit" class="btn btn-primary">Submit</button>
</fieldset>
</form>Validation states
Bootstrap includes validation styles for error, warning, and success states on form controls. To use, add .has-warning, .has-error, or .has-success to the parent element. Any .control-label, .form-control, and .help-block within that element will receive the validation styles.
<div class="form-group has-success">
<label class="control-label" for="inputSuccess1">Input with success</label>
<input type="text" class="form-control" id="inputSuccess1">
</div>
<div class="form-group has-warning">
<label class="control-label" for="inputWarning1">Input with warning</label>
<input type="text" class="form-control" id="inputWarning1">
</div>
<div class="form-group has-error">
<label class="control-label" for="inputError1">Input with error</label>
<input type="text" class="form-control" id="inputError1">
</div>With optional icons
You can also add optional feedback icons with the addition of an extra class and the right icon.
Icons and input groups
When using the feedback icons, be aware that manual positioning may be required for input groups with an add-on on the right. Adjust the right: 0; to an appropriate pixel value depending on the width of your addon.
<div class="form-group has-success has-feedback">
<label class="control-label" for="inputSuccess2">Input with success</label>
<input type="text" class="form-control" id="inputSuccess2">
<span class="glyphicon glyphicon-ok form-control-feedback"></span>
</div>
<div class="form-group has-warning has-feedback">
<label class="control-label" for="inputWarning2">Input with warning</label>
<input type="text" class="form-control" id="inputWarning2">
<span class="glyphicon glyphicon-warning-sign form-control-feedback"></span>
</div>
<div class="form-group has-error has-feedback">
<label class="control-label" for="inputError2">Input with error</label>
<input type="text" class="form-control" id="inputError2">
<span class="glyphicon glyphicon-remove form-control-feedback"></span>
</div>Optional icons also work on horizontal and inline forms.
<form class="form-horizontal" role="form">
<div class="form-group has-success has-feedback">
<label class="control-label col-sm-3" for="inputSuccess3">Input with success</label>
<div class="col-sm-9">
<input type="text" class="form-control" id="inputSuccess3">
<span class="glyphicon glyphicon-ok form-control-feedback"></span>
</div>
</div>
</form><form class="form-inline" role="form">
<div class="form-group has-success has-feedback">
<label class="control-label" for="inputSuccess4">Input with success</label>
<input type="text" class="form-control" id="inputSuccess4">
<span class="glyphicon glyphicon-ok form-control-feedback"></span>
</div>
</form>Control sizing
Set heights using classes like .input-lg, and set widths using grid column classes like .col-lg-*.
Height sizing
Create taller or shorter form controls that match button sizes.
<input class="form-control input-lg" type="text" placeholder=".input-lg">
<input class="form-control" type="text" placeholder="Default input">
<input class="form-control input-sm" type="text" placeholder=".input-sm">
<select class="form-control input-lg">...</select>
<select class="form-control">...</select>
<select class="form-control input-sm">...</select>Column sizing
Wrap inputs in grid columns, or any custom parent element, to easily enforce desired widths.
<div class="row">
<div class="col-xs-2">
<input type="text" class="form-control" placeholder=".col-xs-2">
</div>
<div class="col-xs-3">
<input type="text" class="form-control" placeholder=".col-xs-3">
</div>
<div class="col-xs-4">
<input type="text" class="form-control" placeholder=".col-xs-4">
</div>
</div>Help text
Block level help text for form controls.
<span class="help-block">A block of help text that breaks onto a new line and may extend beyond one line.</span>Buttons
Options
Use any of the available button classes to quickly create a styled button.
<!-- Standard button -->
<button type="button" class="btn btn-default">Default</button>
<!-- Provides extra visual weight and identifies the primary action in a set of buttons -->
<button type="button" class="btn btn-primary">Primary</button>
<!-- Indicates a successful or positive action -->
<button type="button" class="btn btn-success">Success</button>
<!-- Contextual button for informational alert messages -->
<button type="button" class="btn btn-info">Info</button>
<!-- Indicates caution should be taken with this action -->
<button type="button" class="btn btn-warning">Warning</button>
<!-- Indicates a dangerous or potentially negative action -->
<button type="button" class="btn btn-danger">Danger</button>
<!-- Deemphasize a button by making it look like a link while maintaining button behavior -->
<button type="button" class="btn btn-link">Link</button>Sizes
Fancy larger or smaller buttons? Add .btn-lg, .btn-sm, or .btn-xs for additional sizes.
<p>
<button type="button" class="btn btn-primary btn-lg">Large button</button>
<button type="button" class="btn btn-default btn-lg">Large button</button>
</p>
<p>
<button type="button" class="btn btn-primary">Default button</button>
<button type="button" class="btn btn-default">Default button</button>
</p>
<p>
<button type="button" class="btn btn-primary btn-sm">Small button</button>
<button type="button" class="btn btn-default btn-sm">Small button</button>
</p>
<p>
<button type="button" class="btn btn-primary btn-xs">Extra small button</button>
<button type="button" class="btn btn-default btn-xs">Extra small button</button>
</p>Create block level buttons—those that span the full width of a parent— by adding .btn-block.
<button type="button" class="btn btn-primary btn-lg btn-block">Block level button</button>
<button type="button" class="btn btn-default btn-lg btn-block">Block level button</button>Active state
Buttons will appear pressed (with a darker background, darker border, and inset shadow) when active. For <button> elements, this is done via :active. For <a> elements, it’s done with .active. However, you may use .active on <button>s should you need to replicate the active state progammatically.
Button element
No need to add :active as it’s a pseudo-class, but if you need to force the same appearance, go ahead and add .active.
<button type="button" class="btn btn-primary btn-lg active">Primary button</button>
<button type="button" class="btn btn-default btn-lg active">Button</button>Anchor element
Add the .active class to <a> buttons.
<a href="#" class="btn btn-primary btn-lg active" role="button">Primary link</a>
<a href="#" class="btn btn-default btn-lg active" role="button">Link</a>Disabled state
Make buttons look unclickable by fading them back 50%.
Button element
Add the disabled attribute to <button> buttons.
<button type="button" class="btn btn-lg btn-primary" disabled="disabled">Primary button</button>
<button type="button" class="btn btn-default btn-lg" disabled="disabled">Button</button>Cross-browser compatibility
If you add the disabled attribute to a <button>, Internet Explorer 9 and below will render text gray with a nasty text-shadow that we cannot fix.
Anchor element
Add the .disabled class to <a> buttons.
<a href="#" class="btn btn-primary btn-lg disabled" role="button">Primary link</a>
<a href="#" class="btn btn-default btn-lg disabled" role="button">Link</a>
We use .disabled as a utility class here, similar to the common .active class, so no prefix is required.
Link functionality not impacted
This class will only change the <a>’s appearance, not its functionality. Use custom JavaScript to disable links here.
Context-specific usage
While button classes can be used on <a> and <button> elements, only <button> elements are supported within our nav and navbar components.
Button tags
Use the button classes on an <a>, <button>, or <input> element.
<a class="btn btn-default" href="#" role="button">Link</a>
<button class="btn btn-default" type="submit">Button</button>
<input class="btn btn-default" type="button" value="Input">
<input class="btn btn-default" type="submit" value="Submit">Cross-browser rendering
As a best practice, we highly recommend using the <button> element whenever possible to ensure matching cross-browser rendering.
Among other things, there’s a Firefox bug that prevents us from setting the line-height of <input>-based buttons, causing them to not exactly match the height of other buttons on Firefox.
Images
Responsive images
Images in Bootstrap 3 can be made responsive-friendly via the addition of the .img-responsive class. This applies max-width: 100%; and height: auto; to the image so that it scales nicely to the parent element.
<img src="..." class="img-responsive" alt="Responsive image">Image shapes
Add classes to an <img> element to easily style images in any project.
Cross-browser compatibility
Keep in mind that Internet Explorer 8 lacks support for rounded corners.
<img src="..." alt="..." class="img-rounded">
<img src="..." alt="..." class="img-circle">
<img src="..." alt="..." class="img-thumbnail">Helper classes
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.
Fusce dapibus, tellus ac cursus commodo, tortor mauris nibh.
Nullam id dolor id nibh ultricies vehicula ut id elit.
Duis mollis, est non commodo luctus, nisi erat porttitor ligula.
Maecenas sed diam eget risus varius blandit sit amet non magna.
Etiam porta sem malesuada magna mollis euismod.
Donec ullamcorper nulla non metus auctor fringilla.
<p class="text-muted">...</p>
<p class="text-primary">...</p>
<p class="text-success">...</p>
<p class="text-info">...</p>
<p class="text-warning">...</p>
<p class="text-danger">...</p>Dealing with specificity
Sometimes emphasis classes cannot be applied due to the specificity of another selector. In most cases, a sufficient workaround is to wrap your text in a <span> with the class.
Contextual backgrounds
Similar to the contextual text color classes, easily set the background of an element to any contextual class. Anchor components will darken on hover, just like the text classes.
Nullam id dolor id nibh ultricies vehicula ut id elit.
Duis mollis, est non commodo luctus, nisi erat porttitor ligula.
Maecenas sed diam eget risus varius blandit sit amet non magna.
Etiam porta sem malesuada magna mollis euismod.
Donec ullamcorper nulla non metus auctor fringilla.
<p class="bg-primary">...</p>
<p class="bg-success">...</p>
<p class="bg-info">...</p>
<p class="bg-warning">...</p>
<p class="bg-danger">...</p>Close icon
Use the generic close icon for dismissing content like modals and alerts.
<button type="button" class="close" aria-hidden="true">×</button>Carets
Use carets to indicate dropdown functionality and direction. Note that the default caret will reverse automatically in dropup menus.
<span class="caret"></span>Quick 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.
<div class="pull-left">...</div>
<div class="pull-right">...</div>// Classes
.pull-left {
float: left !important;
}
.pull-right {
float: right !important;
}
// Usage as mixins
.element {
.pull-left();
}
.another-element {
.pull-right();
}Not for use in navbars
To align components in navbars with utility classes, use .navbar-left or .navbar-right instead. See the navbar docs for details.
Center content blocks
Set an element to display: block and center via margin. Available as a mixin and class.
<div class="center-block">...</div>// Classes
.center-block {
display: block;
margin-left: auto;
margin-right: auto;
}
// Usage as mixins
.element {
.center-block();
}Clearfix
Clear the float on any element with the .clearfix class. Utilizes the micro clearfix as popularized by Nicolas Gallagher. Can also be used as a mixin.
<!-- Usage as a class -->
<div class="clearfix">...</div>// Mixin itself
.clearfix() {
&:before,
&:after {
content: " ";
display: table;
}
&:after {
clear: both;
}
}
// Usage as a Mixin
.element {
.clearfix();
}Showing and hiding content
Force an element to be shown or hidden (including for screen readers) with the use of .show and .hidden classes. These classes use !important to avoid specificity conflicts, just like the quick floats. They are only available for block level toggling. They can also be used as mixins.
.hide is available, but it does not always affect screen readers and is deprecated as of v3.0.1. Use .hidden or .sr-only instead.
Furthermore, .invisible can be used to toggle only the visibility of an element, meaning its display is not modified and the element can still affect the flow of the document.
<div class="show">...</div>
<div class="hidden">...</div>// Classes
.show {
display: block !important;
}
.hidden {
display: none !important;
visibility: hidden !important;
}
.invisible {
visibility: hidden;
}
// Usage as mixins
.element {
.show();
}
.another-element {
.hidden();
}Screen reader content
Hide an element to all devices except screen readers with .sr-only. Necessary for following accessibility best practices. Can also be used as a mixin.
<a class="sr-only" href="#content">Skip to main content</a>// Usage as a Mixin
.skip-navigation {
.sr-only();
}Image replacement
Utilize the .text-hide class or mixin to help replace an element’s text content with a background image.
<h1 class="text-hide">Custom heading</h1>// Usage as a Mixin
.heading {
.text-hide();
}Responsive utilities
For faster mobile-friendly development, use these utility classes for showing and hiding content by device via media query. Also included are utility classes for toggling content when printed.
Try to use these on a limited basis and avoid creating entirely different versions of the same site. Instead, use them to complement each device’s presentation. Responsive utilities are currently only available for block and table toggling. Use with inline and table elements is currently not supported.
Available classes
Use a single or combination of the available classes for toggling content across viewport breakpoints.
| Extra small devices Phones (<768px) | Small devices Tablets (≥768px) | Medium devices Desktops (≥992px) | Large devices Desktops (≥1200px) | |
|---|---|---|---|---|
.visible-xs |
Visible | Hidden | Hidden | Hidden |
.visible-sm |
Hidden | Visible | Hidden | Hidden |
.visible-md |
Hidden | Hidden | Visible | Hidden |
.visible-lg |
Hidden | Hidden | Hidden | Visible |
.hidden-xs |
Hidden | Visible | Visible | Visible |
.hidden-sm |
Visible | Hidden | Visible | Visible |
.hidden-md |
Visible | Visible | Hidden | Visible |
.hidden-lg |
Visible | Visible | Visible | Hidden |
Print classes
Similar to the regular responsive classes, use these for toggling content for print.
| Class | Browser | |
|---|---|---|
.visible-print |
Hidden | Visible |
.hidden-print |
Visible | Hidden |
Test cases
Resize your browser or load on different devices to test the responsive utility classes.
Visible on…
Green checkmarks indicate the element is visible in your current viewport.
Hidden on…
Here, green checkmarks also indicate the element is hidden in your current viewport.
Using Less
Bootstrap’s CSS is built on Less, a preprocessor with additional functionality like variables, mixins, and functions for compiling CSS. Those looking to use the source Less files instead of our compiled CSS files can make use of the numerous variables and mixins we use throughout the framework.
Grid variables and mixins are covered within the Grid system section.
Compiling Bootstrap
Bootstrap can be used in at least two ways: with the compiled CSS or with the source Less files. To compile the Less files, visit the README for how to setup your development environment to run the necessary commands.
Third party compilation tools may work with Bootstrap, but they are not supported by our core team.
Variables
Variables are used throughout the entire project as a way to centralize and share commonly used values like colors, spacing, or font stacks. For a complete breakdown, please see the Customizer.
Colors
Easily make use of two color schemes: grayscale and semantic. Grayscale colors provide quick access to commonly used shades of black while semantic include various colors assigned to meaningful contextual values.
@gray-darker: lighten(#000, 13.5%); // #222
@gray-dark: lighten(#000, 20%); // #333
@gray: lighten(#000, 33.5%); // #555
@gray-light: lighten(#000, 60%); // #999
@gray-lighter: lighten(#000, 93.5%); // #eee@brand-primary: #428bca;
@brand-success: #5cb85c;
@brand-info: #5bc0de;
@brand-warning: #f0ad4e;
@brand-danger: #d9534f;Use any of these color variables as they are or reassign them to more meaningful variables for your project.
// Use as-is
.masthead {
background-color: @brand-primary;
}
// Reassigned variables in Less
@alert-message-background: @brand-info;
.alert {
background-color: @alert-message-background;
}Scaffolding
A handful of variables for quickly customizing key elements of your site’s skeleton.
// Scaffolding
@body-bg: #fff;
@text-color: @black-50;Links
Easily style your links with the right color with only one value.
// Variables
@link-color: @brand-primary;
@link-color-hover: darken(@link-color, 15%);
// Usage
a {
color: @link-color;
text-decoration: none;
&:hover {
color: @link-color-hover;
text-decoration: underline;
}
}Note that the @link-color-hover uses a function, another awesome tool from Less, to automagically create the right hover color. You can use darken, lighten, saturate, and desaturate.
Typography
Easily set your type face, text size, leading, and more with a few quick variables. Bootstrap makes use of these as well to provide easy typographic mixins.
@font-family-sans-serif: "Helvetica Neue", Helvetica, Arial, sans-serif;
@font-family-serif: Georgia, "Times New Roman", Times, serif;
@font-family-monospace: Menlo, Monaco, Consolas, "Courier New", monospace;
@font-family-base: @font-family-sans-serif;
@font-size-base: 14px;
@font-size-large: ceil((@font-size-base * 1.25)); // ~18px
@font-size-small: ceil((@font-size-base * 0.85)); // ~12px
@font-size-h1: floor((@font-size-base * 2.6)); // ~36px
@font-size-h2: floor((@font-size-base * 2.15)); // ~30px
@font-size-h3: ceil((@font-size-base * 1.7)); // ~24px
@font-size-h4: ceil((@font-size-base * 1.25)); // ~18px
@font-size-h5: @font-size-base;
@font-size-h6: ceil((@font-size-base * 0.85)); // ~12px
@line-height-base: 1.428571429; // 20/14
@line-height-computed: floor((@font-size-base * @line-height-base)); // ~20px
@headings-font-family: inherit;
@headings-font-weight: 500;
@headings-line-height: 1.1;
@headings-color: inherit;Icons
Two quick variables for customizing the location and filename of your icons.
@icon-font-path: "../fonts/";
@icon-font-name: "glyphicons-halflings-regular";Components
Components throughout Bootstrap make use of some default variables for setting common values. Here are the most commonly used.
@padding-base-vertical: 6px;
@padding-base-horizontal: 12px;
@padding-large-vertical: 10px;
@padding-large-horizontal: 16px;
@padding-small-vertical: 5px;
@padding-small-horizontal: 10px;
@padding-xs-vertical: 1px;
@padding-xs-horizontal: 5px;
@line-height-large: 1.33;
@line-height-small: 1.5;
@border-radius-base: 4px;
@border-radius-large: 6px;
@border-radius-small: 3px;
@component-active-color: #fff;
@component-active-bg: @brand-primary;
@caret-width-base: 4px;
@caret-width-large: 5px;Vendor mixins
Vendor mixins are mixins to help support multiple browsers by including all relevant vendor prefixes in your compiled CSS.
Box-sizing
Reset your components’ box model with a single mixin. For context, see this helpful article from Mozilla.
.box-sizing(@box-model) {
-webkit-box-sizing: @box-model; // Safari <= 5
-moz-box-sizing: @box-model; // Firefox <= 19
box-sizing: @box-model;
}Rounded corners
Today all modern browsers support the non-prefixed border-radius property. As such, there is no .border-radius() mixin, but Bootstrap does include shortcuts for quickly rounding two corners on a particular side of an object.
.border-top-radius(@radius) {
border-top-right-radius: @radius;
border-top-left-radius: @radius;
}
.border-right-radius(@radius) {
border-bottom-right-radius: @radius;
border-top-right-radius: @radius;
}
.border-bottom-radius(@radius) {
border-bottom-right-radius: @radius;
border-bottom-left-radius: @radius;
}
.border-left-radius(@radius) {
border-bottom-left-radius: @radius;
border-top-left-radius: @radius;
}Box (Drop) shadows
If your target audience is using the latest and greatest browsers and devices, be sure to just use the box-shadow property on its own. If you need support for older Android (pre-v4) and iOS devices (pre-iOS 5), use the deprecated mixin to pick up the required -webkit prefix.
The mixin is deprecated as of v3.1.0, since Bootstrap doesn’t officially support the outdated platforms that don’t support the standard property. To preserve backwards-compatibility, Bootstrap will continue to use the mixin internally until Bootstrap v4.
Be sure to use rgba() colors in your box shadows so they blend as seamlessly as possible with backgrounds.
.box-shadow(@shadow: 0 1px 3px rgba(0,0,0,.25)) {
-webkit-box-shadow: @shadow; // iOS <4.3 & Android <4.1
box-shadow: @shadow;
}Transitions
Three mixins for flexibility. Set all transition information with one, or specify a separate delay and duration as needed.
.transition(@transition) {
-webkit-transition: @transition;
transition: @transition;
}
.transition-property(@transition-property) {
-webkit-transition-property: @transition-property;
transition-property: @transition-property;
}
.transition-delay(@transition-delay) {
-webkit-transition-delay: @transition-delay;
transition-delay: @transition-delay;
}
.transition-duration(@transition-duration) {
-webkit-transition-duration: @transition-duration;
transition-duration: @transition-duration;
}
.transition-transform(@transition) {
-webkit-transition: -webkit-transform @transition;
-moz-transition: -moz-transform @transition;
-o-transition: -o-transform @transition;
transition: transform @transition;
}Transformations
Rotate, scale, translate (move), or skew any object.
.rotate(@degrees) {
-webkit-transform: rotate(@degrees);
-ms-transform: rotate(@degrees); // IE9 only
transform: rotate(@degrees);
}
.scale(@ratio; @ratio-y...) {
-webkit-transform: scale(@ratio, @ratio-y);
-ms-transform: scale(@ratio, @ratio-y); // IE9 only
transform: scale(@ratio, @ratio-y);
}
.translate(@x; @y) {
-webkit-transform: translate(@x, @y);
-ms-transform: translate(@x, @y); // IE9 only
transform: translate(@x, @y);
}
.skew(@x; @y) {
-webkit-transform: skew(@x, @y);
-ms-transform: skewX(@x) skewY(@y); // See https://github.com/twbs/bootstrap/issues/4885; IE9+
transform: skew(@x, @y);
}
.translate3d(@x; @y; @z) {
-webkit-transform: translate3d(@x, @y, @z);
transform: translate3d(@x, @y, @z);
}
.rotateX(@degrees) {
-webkit-transform: rotateX(@degrees);
-ms-transform: rotateX(@degrees); // IE9 only
transform: rotateX(@degrees);
}
.rotateY(@degrees) {
-webkit-transform: rotateY(@degrees);
-ms-transform: rotateY(@degrees); // IE9 only
transform: rotateY(@degrees);
}
.perspective(@perspective) {
-webkit-perspective: @perspective;
-moz-perspective: @perspective;
perspective: @perspective;
}
.perspective-origin(@perspective) {
-webkit-perspective-origin: @perspective;
-moz-perspective-origin: @perspective;
perspective-origin: @perspective;
}
.transform-origin(@origin) {
-webkit-transform-origin: @origin;
-moz-transform-origin: @origin;
-ms-transform-origin: @origin; // IE9 only
transform-origin: @origin;
}Animations
A single mixin for using all of CSS3’s animation properties in one declaration and other mixins for individual properties.
.animation(@animation) {
-webkit-animation: @animation;
animation: @animation;
}
.animation-name(@name) {
-webkit-animation-name: @name;
animation-name: @name;
}
.animation-duration(@duration) {
-webkit-animation-duration: @duration;
animation-duration: @duration;
}
.animation-timing-function(@timing-function) {
-webkit-animation-timing-function: @timing-function;
animation-timing-function: @timing-function;
}
.animation-delay(@delay) {
-webkit-animation-delay: @delay;
animation-delay: @delay;
}
.animation-iteration-count(@iteration-count) {
-webkit-animation-iteration-count: @iteration-count;
animation-iteration-count: @iteration-count;
}
.animation-direction(@direction) {
-webkit-animation-direction: @direction;
animation-direction: @direction;
}Opacity
Set the opacity for all browsers and provide a filter fallback for IE8.
.opacity(@opacity) {
opacity: @opacity;
// IE8 filter
@opacity-ie: (@opacity * 100);
filter: ~"alpha(opacity=@{opacity-ie})";
}Placeholder text
Provide context for form controls within each field.
.placeholder(@color: @input-color-placeholder) {
&:-moz-placeholder { color: @color; } // Firefox 4-18
&::-moz-placeholder { color: @color; } // Firefox 19+
&:-ms-input-placeholder { color: @color; } // Internet Explorer 10+
&::-webkit-input-placeholder { color: @color; } // Safari and Chrome
}Columns
Generate columns via CSS within a single element.
.content-columns(@width; @count; @gap) {
-webkit-column-width: @width;
-moz-column-width: @width;
column-width: @width;
-webkit-column-count: @count;
-moz-column-count: @count;
column-count: @count;
-webkit-column-gap: @gap;
-moz-column-gap: @gap;
column-gap: @gap;
}Gradients
Easily turn any two colors into a background gradient. Get more advanced and set a direction, use three colors, or use a radial gradient. With a single mixin you get all the prefixed syntaxes you’ll need.
#gradient > .vertical(#333; #000);
#gradient > .horizontal(#333; #000);
#gradient > .radial(#333; #000);You can also specify the angle of a standard two-color, linear gradient:
#gradient > .directional(#333; #000; 45deg);If you need a barber-stripe style gradient, that’s easy, too. Just specify a single color and we’ll overlay a translucent white stripe.
#gradient > .striped(#333; #000; 45deg);Up the ante and use three colors instead. Set the first color, the second color, the second color’s color stop (a decimal value like 0.25), and the third color with these mixins:
#gradient > .vertical-three-colors(#777; #333; .25; #000);
#gradient > .horizontal-three-colors(#777; #333; .25; #000);Heads up! Should you ever need to remove a gradient, be sure to remove any IE-specific filter you may have added. You can do that by using the .reset-filter() mixin alongside background-image: none;.
Utility mixins
Utility mixins are mixins that combine otherwise unrelated CSS properties to achieve a specific goal or task.
Clearfix
Forget adding class="clearfix" to any element and instead add the .clearfix() mixin where appropriate. Uses the micro clearfix from Nicolas Gallager.
// Mixin
.clearfix() {
&:before,
&:after {
content: " ";
display: table;
}
&:after {
clear: both;
}
}
// Usage
.container {
.clearfix();
}Horizontal centering
Quickly center any element within its parent. Requires width or max-width to be set.
// Mixin
.center-block() {
display: block;
margin-left: auto;
margin-right: auto;
}
// Usage
.container {
width: 940px;
.center-block();
}Sizing helpers
Specify the dimensions of an object more easily.
// Mixins
.size(@width; @height) {
width: @width;
height: @height;
}
.square(@size) {
.size(@size; @size);
}
// Usage
.image { .size(400px; 300px); }
.avatar { .square(48px); }Resizable textareas
Easily configure the resize options for any textarea, or any other element. Defaults to normal browser behavior (both).
.resizable(@direction: both) {
// Options: horizontal, vertical, both
resize: @direction;
// Safari fix
overflow: auto;
}Truncating text
Easily truncate text with an ellipsis with a single mixin. Requires element to be block or inline-block level.
// Mixin
.text-overflow() {
overflow: hidden;
text-overflow: ellipsis;
white-space: nowrap;
}
// Usage
.branch-name {
display: inline-block;
max-width: 200px;
.text-overflow();
}Retina images
Specify two image paths and the @1x image dimensions, and Bootstrap will provide an @2x media query. If you have many images to serve, consider writing your retina image CSS manually in a single media query.
.img-retina(@file-1x; @file-2x; @width-1x; @height-1x) {
background-image: url("@{file-1x}");
@media
only screen and (-webkit-min-device-pixel-ratio: 2),
only screen and ( min--moz-device-pixel-ratio: 2),
only screen and ( -o-min-device-pixel-ratio: 2/1),
only screen and ( min-device-pixel-ratio: 2),
only screen and ( min-resolution: 192dpi),
only screen and ( min-resolution: 2dppx) {
background-image: url("@{file-2x}");
background-size: @width-1x @height-1x;
}
}
// Usage
.jumbotron {
.img-retina("/img/bg-1x.png", "/img/bg-2x.png", 100px, 100px);
}Using Sass
While Bootstrap is built on Less, it also has an official Sass port. We maintain it in a separate GitHub repository and handle updates with a conversion script.
What’s included
Since the Sass port has a separate repo and serves a slightly different audience, the contents of the project differ greatly from the main Bootstrap project. This ensures the Sass port is as compatible with as many Sass-based systems as possible.
| Path | Description |
|---|---|
lib/ |
Ruby gem code (Sass configuration, Rails and Compass integrations) |
tasks/ |
Converter scripts (turning upstream Less to Sass) |
test/ |
Compilation tests |
templates/ |
Compass package manifest |
vendor/assets/ |
Sass, JavaScript, and font files |
Rakefile |
Internal tasks, such as rake and convert |
Visit the Sass port’s GitHub repository to see these files in action.
Installation
For information on how to install and use Bootstrap for Sass, consult the GitHub repository readme. It’s the most up to date source and includes information for use with Rails, Compass, and standard Sass projects.