bootstrap Documentation

The most popular HTML, CSS, and JavaScript framework for developing responsive, mobile first projects on the web.

174,577 stars MDX 1 file · ~5,655 tokens #bootstrap#css#css-framework#html#javascript#sass#scss
RAW Doc

File: README.md

Bootstrap

Bootstrap 5

Our default branch is for development of our Bootstrap 5 release. Head to the v4-dev branch to view the readme, documentation, and source code for Bootstrap 4.

Table of contents

Quick start

Several quick start options are available:

Read the Getting started page for information on the framework contents, templates, examples, and more.

Status












What’s included

Within the download you’ll find the following directories and files, logically grouping common assets and providing both compiled and minified variations.

Download contents

text
bootstrap/
├── css/
│   ├── bootstrap-grid.css
│   ├── bootstrap-grid.css.map
│   ├── bootstrap-grid.min.css
│   ├── bootstrap-grid.min.css.map
│   ├── bootstrap-grid.rtl.css
│   ├── bootstrap-grid.rtl.css.map
│   ├── bootstrap-grid.rtl.min.css
│   ├── bootstrap-grid.rtl.min.css.map
│   ├── bootstrap-reboot.css
│   ├── bootstrap-reboot.css.map
│   ├── bootstrap-reboot.min.css
│   ├── bootstrap-reboot.min.css.map
│   ├── bootstrap-reboot.rtl.css
│   ├── bootstrap-reboot.rtl.css.map
│   ├── bootstrap-reboot.rtl.min.css
│   ├── bootstrap-reboot.rtl.min.css.map
│   ├── bootstrap-utilities.css
│   ├── bootstrap-utilities.css.map
│   ├── bootstrap-utilities.min.css
│   ├── bootstrap-utilities.min.css.map
│   ├── bootstrap-utilities.rtl.css
│   ├── bootstrap-utilities.rtl.css.map
│   ├── bootstrap-utilities.rtl.min.css
│   ├── bootstrap-utilities.rtl.min.css.map
│   ├── bootstrap.css
│   ├── bootstrap.css.map
│   ├── bootstrap.min.css
│   ├── bootstrap.min.css.map
│   ├── bootstrap.rtl.css
│   ├── bootstrap.rtl.css.map
│   ├── bootstrap.rtl.min.css
│   └── bootstrap.rtl.min.css.map
└── js/
    ├── bootstrap.bundle.js
    ├── bootstrap.bundle.js.map
    ├── bootstrap.bundle.min.js
    ├── bootstrap.bundle.min.js.map
    ├── bootstrap.esm.js
    ├── bootstrap.esm.js.map
    ├── bootstrap.esm.min.js
    ├── bootstrap.esm.min.js.map
    ├── bootstrap.js
    ├── bootstrap.js.map
    ├── bootstrap.min.js
    └── bootstrap.min.js.map

We provide compiled CSS and JS (bootstrap.*), as well as compiled and minified CSS and JS (bootstrap.min.*). Source maps (bootstrap.*.map) are available for use with certain browsers’ developer tools. Bundled JS files (bootstrap.bundle.js and minified bootstrap.bundle.min.js) include Popper.

Bugs and feature requests

Have a bug or a feature request? Please first read the issue guidelines and search for existing and closed issues. If your problem or idea is not addressed yet, please open a new issue.

Documentation

Bootstrap’s documentation, included in this repo in the root directory, is built with Astro and publicly hosted on GitHub Pages at https://getbootstrap.com/. The docs may also be run locally.

Documentation search is powered by Algolia's DocSearch.

Running documentation locally

  1. Run npm install to install the Node.js dependencies, including Astro (the site builder).
  2. Run npm run test (or a specific npm script) to rebuild distributed CSS and JavaScript files, as well as our docs assets.
  3. From the root /bootstrap directory, run npm run docs-serve in the command line.
  4. Open http://localhost:9001 in your browser, and voilà.

Learn more about using Astro by reading its documentation.

Documentation for previous releases

You can find all our previous releases docs on https://getbootstrap.com/docs/versions/.

Previous releases and their documentation are also available for download.

Contributing

Please read through our contributing guidelines. Included are directions for opening issues, coding standards, and notes on development.

Moreover, if your pull request contains JavaScript patches or features, you must include relevant unit tests. All HTML and CSS should conform to the Code Guide, maintained by Mark Otto.

Editor preferences are available in the editor config for easy use in common text editors. Read more and download plugins at https://editorconfig.org/.

Community

Get updates on Bootstrap’s development and chat with the project maintainers and community members.

Versioning

For transparency into our release cycle and in striving to maintain backward compatibility, Bootstrap is maintained under the Semantic Versioning guidelines. Sometimes we screw up, but we adhere to those rules whenever possible.

See the Releases section of our GitHub project for changelogs for each release version of Bootstrap. Release announcement posts on the official Bootstrap blog contain summaries of the most noteworthy changes made in each release.

Creators

Mark Otto

Jacob Thornton

Thanks

Thanks to BrowserStack for providing the infrastructure that allows us to test in real browsers!

Thanks to Netlify for providing us with Deploy Previews!

Sponsors

Support this project by becoming a sponsor. Your logo will show up here with a link to your website. [Become a sponsor]










Backers

Thank you to all our backers! 🙏 [Become a backer]

Code and documentation copyright 2011-2026 the Bootstrap Authors. Code released under the MIT License. Docs released under Creative Commons.

File: site/src/content/callouts/danger-async-methods.md

All API methods are asynchronous and start a transition. They return to the caller as soon as the transition is started, but before it ends. In addition, a method call on a transitioning component will be ignored. Learn more in our JavaScript docs.

File: site/src/content/callouts/info-mediaqueries-breakpoints.md

Why subtract .02px? Browsers don’t currently support range context queries, so we work around the limitations of min- and max- prefixes and viewports with fractional widths (which can occur under certain conditions on high-dpi devices, for instance) by using values with higher precision.

File: site/src/content/callouts/info-npm-starter.md

Get started with Bootstrap via npm with our starter project! Head to the Sass & JS example template repository to see how to build and customize Bootstrap in your own npm project. Includes Sass compiler, Autoprefixer, Stylelint, PurgeCSS, and Bootstrap Icons.

File: site/src/content/callouts/info-prefersreducedmotion.md

The animation effect of this component is dependent on the prefers-reduced-motion media query. See the reduced motion section of our accessibility documentation.

File: site/src/content/callouts/info-sanitizer.md

By default, this component uses the built-in content sanitizer, which strips out any HTML elements that are not explicitly allowed. See the sanitizer section in our JavaScript documentation for more details.

File: site/src/content/callouts/warning-color-assistive-technologies.md

Accessibility tip: Using color to add meaning only provides a visual indication, which will not be conveyed to users of assistive technologies like screen readers. Please ensure the meaning is obvious from the content itself (e.g., the visible text with a sufficient color contrast) or is included through alternative means, such as additional text hidden with the .visually-hidden class.

File: site/src/content/callouts/warning-data-bs-title-vs-title.md

Feel free to use either title or data-bs-title in your HTML. When title is used, Popper will replace it automatically with data-bs-title when the element is rendered.

File: site/src/content/callouts/warning-input-support.md

Some date inputs types are not fully supported by the latest versions of Safari and Firefox.

File: site/src/content/docs/customize/color.mdx

title: Color toc: true

import { getData } from '@libs/data'
import { getSequence } from '@libs/utils'

Colors

Bootstrap’s color palette has continued to expand and become more nuanced in v5.3.0. We’ve added new variables for secondary and tertiary text and background colors, plus {color}-bg-subtle, {color}-border-subtle, and {color}-text-emphasis for our theme colors. These new colors are available through Sass and CSS variables (but not our color maps or utility classes) with the express goal of making it easier to customize across multiple colors modes like light and dark. These new variables are globally set on :root and are adapted for our new dark color mode while our original theme colors remain unchanged.

Colors ending in -rgb provide the red, green, blue values for use in rgb() and rgba() color modes. For example, rgba(var(--bs-secondary-bg-rgb), .5).

**Heads up!** There’s some potential confusion with our new secondary and tertiary colors, and our existing secondary theme color, as well as our light and dark theme colors. Expect this to be ironed out in v6.
Description Swatch Variables
Body — Default foreground (color) and background, including components.   --bs-body-color``--bs-body-color-rgb
  --bs-body-bg``--bs-body-bg-rgb
Secondary — Use the color option for lighter text. Use the bg option for dividers and to indicate disabled component states.   --bs-secondary-color``--bs-secondary-color-rgb
  --bs-secondary-bg``--bs-secondary-bg-rgb
Tertiary — Use the color option for even lighter text. Use the bg option to style backgrounds for hover states, accents, and wells.   --bs-tertiary-color``--bs-tertiary-color-rgb
  --bs-tertiary-bg``--bs-tertiary-bg-rgb
Emphasis — For higher contrast text. Not applicable for backgrounds.   --bs-emphasis-color``--bs-emphasis-color-rgb
Border — For component borders, dividers, and rules. Use --bs-border-color-translucent to blend with backgrounds with an rgba() value.   --bs-border-color``--bs-border-color-rgb
Primary — Main theme color, used for hyperlinks, focus styles, and component and form active states.   --bs-primary``--bs-primary-rgb
  --bs-primary-bg-subtle
  --bs-primary-border-subtle
Text --bs-primary-text-emphasis
Success — Theme color used for positive or successful actions and information.   --bs-success``--bs-success-rgb
  --bs-success-bg-subtle
  --bs-success-border-subtle
Text --bs-success-text-emphasis
Danger — Theme color used for errors and dangerous actions.   --bs-danger``--bs-danger-rgb
  --bs-danger-bg-subtle
  --bs-danger-border-subtle
Text --bs-danger-text-emphasis
Warning — Theme color used for non-destructive warning messages.   --bs-warning``--bs-warning-rgb
  --bs-warning-bg-subtle
  --bs-warning-border-subtle
Text --bs-warning-text-emphasis
Info — Theme color used for neutral and informative content.   --bs-info``--bs-info-rgb
  --bs-info-bg-subtle
  --bs-info-border-subtle
Text --bs-info-text-emphasis
Light — Additional theme option for less contrasting colors.   --bs-light``--bs-light-rgb
  --bs-light-bg-subtle
  --bs-light-border-subtle
Text --bs-light-text-emphasis
Dark — Additional theme option for higher contrasting colors.   --bs-dark``--bs-dark-rgb
  --bs-dark-bg-subtle
  --bs-dark-border-subtle
Text --bs-dark-text-emphasis

Using the new colors

These new colors are accessible via CSS variables and utility classes—like --bs-primary-bg-subtle and .bg-primary-subtle—allowing you to compose your own CSS rules with the variables, or to quickly apply styles via classes. The utilities are built with the color’s associated CSS variables, and since we customize those CSS variables for dark mode, they are also adaptive to color mode by default.

<Example code={ Example element with utilities } />

Theme colors

We use a subset of all colors to create a smaller color palette for generating color schemes, also available as Sass variables and a Sass map in Bootstrap’s scss/_variables.scss file.

{getData('theme-colors').map((themeColor) => {
return (

text
{themeColor.title}
  
)

})}

All these colors are available as a Sass map, $theme-colors.

Check out our Sass maps and loops docs for how to modify these colors.

All colors

All Bootstrap colors are available as Sass variables and a Sass map in scss/_variables.scss file. To avoid increased file sizes, we don’t create text or background color classes for each of these variables. Instead, we choose a subset of these colors for a theme palette.

Be sure to monitor contrast ratios as you customize colors. As shown below, we’ve added three contrast ratios to each of the main colors—one for the swatch’s current colors, one for against white, and one for against black.

{getData('colors').map((color) => {
if ((color.name !== "white") && (color.name !== "gray") && (color.name !== "gray-dark")) {
return (

text
${color.name}
        {color.hex}
      

      {getSequence(100, 900, 100).map((value) => {
        return (
          ${color.name}-{value}
        )
      })}
    
  )
}

})}

text
$gray-500#adb5bd
{getData('grays').map((gray) => {
  return (
    $gray-{gray.name}
  )
})}




  $black
  #000


  $white
  #fff

Notes on Sass

Sass cannot programmatically generate variables, so we manually created variables for every tint and shade ourselves. We specify the midpoint value (e.g., $blue-500) and use custom color functions to tint (lighten) or shade (darken) our colors via Sass’s mix() color function.

Using mix() is not the same as lighten() and darken()—the former blends the specified color with white or black, while the latter only adjusts the lightness value of each color. The result is a much more complete suite of colors, as shown in this CodePen demo.

Our tint-color() and shade-color() functions use mix() alongside our $theme-color-interval variable, which specifies a stepped percentage value for each mixed color we produce. See the scss/_functions.scss and scss/_variables.scss files for the full source code.

Color Sass maps

Bootstrap’s source Sass files include three maps to help you quickly and easily loop over a list of colors and their hex values.

  • $colors lists all our available base (500) colors
  • $theme-colors lists all semantically named theme colors (shown below)
  • $grays lists all tints and shades of gray

Within scss/_variables.scss, you’ll find Bootstrap’s color variables and Sass map. Here’s an example of the $colors Sass map:

Add, remove, or modify values within the map to update how they’re used in many other components. Unfortunately at this time, not every component utilizes this Sass map. Future updates will strive to improve upon this. Until then, plan on making use of the ${color} variables and this Sass map.

Example

Here’s how you can use these in your Sass:

scss
.alpha { color: $purple; }
.beta {
  color: $yellow-300;
  background-color: $indigo-900;
}

Color and background utility classes are also available for setting color and background-color using the 500 color values.

Generating utilities

Bootstrap doesn’t include color and background-color utilities for every color variable, but you can generate these yourself with our utility API and our extended Sass maps added in v5.1.0.

  1. To start, make sure you’ve imported our functions, variables, mixins, and utilities.
  2. Use our map-merge-multiple() function to quickly merge multiple Sass maps together in a new map.
  3. Merge this new combined map to extend any utility with a {color}-{level} class name.

Here’s an example that generates text color utilities (e.g., .text-purple-500) using the above steps.

scss
@import "bootstrap/scss/functions";
@import "bootstrap/scss/variables";
@import "bootstrap/scss/variables-dark";
@import "bootstrap/scss/maps";
@import "bootstrap/scss/mixins";
@import "bootstrap/scss/utilities";

$all-colors: map-merge-multiple($blues, $indigos, $purples, $pinks, $reds, $oranges, $yellows, $greens, $teals, $cyans);

$utilities: map-merge(
  $utilities,
  (
    "color": map-merge(
      map-get($utilities, "color"),
      (
        values: map-merge(
          map-get(map-get($utilities, "color"), "values"),
          (
            $all-colors
          ),
        ),
      ),
    ),
  )
);

@import "bootstrap/scss/utilities/api";

This will generate new .text-{color}-{level} utilities for every color and level. You can do the same for any other utility and property as well.

Explore Related Technologies & Topics

View All 9,111+ Repositories →

Discover similar high-velocity repositories, agent skills, and OpenAPI specifications across the ecosystem.

#bootstrap Browse bootstrap catalog → #css Browse css catalog → #css-framework Browse css-framework catalog → #html Browse html catalog → #javascript Browse javascript catalog → #sass Browse sass catalog → ⚡ MCP Servers Model Context Protocol → 🧠 Agent Skills Prompt & rule files → 🔌 OpenAPI Specs REST & Swagger schemas →