0
0
mirror of https://github.com/twbs/bootstrap.git synced 2024-12-14 02:24:00 +01:00
Bootstrap/docs/4.0/layout/overview/index.html
2017-08-10 21:31:22 -07:00

1238 lines
40 KiB
HTML
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<title>
Overview &middot; Bootstrap
</title>
<!-- Twitter -->
<meta name="twitter:site" content="@getbootstrap">
<meta name="twitter:creator" content="@getbootstrap">
<meta name="twitter:card" content="summary">
<meta name="twitter:title" content="Overview">
<meta name="twitter:description" content="Components and options for laying out your Bootstrap project, including wrapping containers, a powerful grid system, a flexible media object, and responsive utility classes.">
<meta name="twitter:image" content="https://getbootstrap.com/assets/brand/bootstrap-social-logo.png">
<!-- Facebook -->
<meta property="og:url" content="https://getbootstrap.com/docs/4.0/layout/overview/">
<meta property="og:title" content="Overview">
<meta property="og:description" content="Components and options for laying out your Bootstrap project, including wrapping containers, a powerful grid system, a flexible media object, and responsive utility classes.">
<meta property="og:type" content="website">
<meta property="og:image" content="http://getbootstrap.com/assets/brand/bootstrap-social.png">
<meta property="og:image:secure_url" content="https://getbootstrap.com/assets/brand/bootstrap-social.png">
<meta property="og:image:type" content="image/png">
<meta property="og:image:width" content="1200">
<meta property="og:image:height" content="630">
<!-- Meta -->
<meta name="description" content="The most popular HTML, CSS, and JS library in the world.">
<meta name="author" content="Mark Otto, Jacob Thornton, and Bootstrap contributors">
<!-- Bootstrap core CSS -->
<link href="/dist/css/bootstrap.min.css" rel="stylesheet">
<!-- Documentation extras -->
<link rel="stylesheet" href="https://cdn.jsdelivr.net/docsearch.js/2/docsearch.min.css" />
<link href="/assets/css/docs.min.css" rel="stylesheet">
<!-- Favicons -->
<link rel="apple-touch-icon" href="/apple-touch-icon.png">
<link rel="icon" href="/favicon.ico">
<script>
(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
})(window,document,'script','https://www.google-analytics.com/analytics.js','ga');
ga('create', 'UA-146052-10', 'getbootstrap.com');
ga('send', 'pageview');
</script>
</head>
<body class="bd-docs" data-spy="scroll" data-target=".bd-sidenav-active">
<a id="skippy" class="sr-only sr-only-focusable" href="#content">
<div class="container">
<span class="skiplink-text">Skip to main content</span>
</div>
</a>
<header class="navbar navbar-expand navbar-dark flex-column flex-md-row bd-navbar">
<a class="navbar-brand mr-0 mr-md-2" href="/" aria-label="Bootstrap">
<svg class="d-block" width="36" height="36" viewbox="0 0 612 612" xmlns="http://www.w3.org/2000/svg" focusable="false"><title>Bootstrap</title><path fill="currentColor" d="M510 8a94.3 94.3 0 0 1 94 94v408a94.3 94.3 0 0 1-94 94H102a94.3 94.3 0 0 1-94-94V102a94.3 94.3 0 0 1 94-94h408m0-8H102C45.9 0 0 45.9 0 102v408c0 56.1 45.9 102 102 102h408c56.1 0 102-45.9 102-102V102C612 45.9 566.1 0 510 0z"/><path fill="currentColor" d="M196.77 471.5V154.43h124.15c54.27 0 91 31.64 91 79.1 0 33-24.17 63.72-54.71 69.21v1.76c43.07 5.49 70.75 35.82 70.75 78 0 55.81-40 89-107.45 89zm39.55-180.4h63.28c46.8 0 72.29-18.68 72.29-53 0-31.42-21.53-48.78-60-48.78h-75.57zm78.22 145.46c47.68 0 72.73-19.34 72.73-56s-25.93-55.37-76.46-55.37h-74.49v111.4z"/></svg>
</a>
<div class="navbar-nav-scroll">
<ul class="navbar-nav bd-navbar-nav flex-row">
<li class="nav-item">
<a class="nav-link " href="/" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Bootstrap');">Home</a>
</li>
<li class="nav-item">
<a class="nav-link active" href="/docs/4.0/" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Docs');">Documentation</a>
</li>
<li class="nav-item">
<a class="nav-link " href="/docs/4.0/examples/" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Examples');">Examples</a>
</li>
<li class="nav-item">
<a class="nav-link" href="https://themes.getbootstrap.com" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Themes');" target="_blank" rel="noopener">Themes</a>
</li>
<li class="nav-item">
<a class="nav-link" href="https://jobs.getbootstrap.com" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Jobs');" target="_blank" rel="noopener">Jobs</a>
</li>
<li class="nav-item">
<a class="nav-link" href="https://expo.getbootstrap.com" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Expo');" target="_blank" rel="noopener">Expo</a>
</li>
<li class="nav-item">
<a class="nav-link" href="https://blog.getbootstrap.com" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Blog');" target="_blank" rel="noopener">Blog</a>
</li>
</ul>
</div>
<ul class="navbar-nav flex-row ml-md-auto d-none d-md-flex">
<li class="nav-item dropdown">
<a class="nav-item nav-link dropdown-toggle mr-md-2" href="#" id="bd-versions" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
v4.0
</a>
<div class="dropdown-menu dropdown-menu-right" aria-labelledby="bd-versions">
<a class="dropdown-item active" href="/docs/4.0/">Latest (4.x)</a>
<a class="dropdown-item" href="https://v4-alpha.getbootstrap.com">v4 Alpha 6</a>
<a class="dropdown-item" href="https://getbootstrap.com/docs/3.3/">v3.3.7</a>
<a class="dropdown-item" href="https://getbootstrap.com/2.3.2/">v2.3.2</a>
</div>
</li>
<li class="nav-item">
<a class="nav-link p-2" href="https://github.com/twbs/bootstrap" target="_blank" rel="noopener" aria-label="GitHub">
<svg class="navbar-nav-svg" xmlns="http://www.w3.org/2000/svg" viewbox="0 0 512 499.36" focusable="false"><title>GitHub</title><path d="M256 0C114.64 0 0 114.61 0 256c0 113.09 73.34 209 175.08 242.9 12.8 2.35 17.47-5.56 17.47-12.34 0-6.08-.22-22.18-.35-43.54-71.2 15.49-86.2-34.34-86.2-34.34-11.64-29.57-28.42-37.45-28.42-37.45-23.27-15.84 1.73-15.55 1.73-15.55 25.69 1.81 39.21 26.38 39.21 26.38 22.84 39.12 59.92 27.82 74.5 21.27 2.33-16.54 8.94-27.82 16.25-34.22-56.84-6.43-116.6-28.43-116.6-126.49 0-27.95 10-50.8 26.35-68.69-2.63-6.48-11.42-32.5 2.51-67.75 0 0 21.49-6.88 70.4 26.24a242.65 242.65 0 0 1 128.18 0c48.87-33.13 70.33-26.24 70.33-26.24 14 35.25 5.18 61.27 2.55 67.75 16.41 17.9 26.31 40.75 26.31 68.69 0 98.35-59.85 120-116.88 126.32 9.19 7.9 17.38 23.53 17.38 47.41 0 34.22-.31 61.83-.31 70.23 0 6.85 4.61 14.81 17.6 12.31C438.72 464.97 512 369.08 512 256.02 512 114.62 397.37 0 256 0z" fill="currentColor" fill-rule="evenodd"/></svg>
</a>
</li>
<li class="nav-item">
<a class="nav-link p-2" href="https://twitter.com/getbootstrap" target="_blank" rel="noopener" aria-label="Twitter">
<svg class="navbar-nav-svg" xmlns="http://www.w3.org/2000/svg" viewbox="0 0 512 416.32" focusable="false"><title>Twitter</title><path d="M160.83 416.32c193.2 0 298.92-160.22 298.92-298.92 0-4.51 0-9-.2-13.52A214 214 0 0 0 512 49.38a212.93 212.93 0 0 1-60.44 16.6 105.7 105.7 0 0 0 46.3-58.19 209 209 0 0 1-66.79 25.37 105.09 105.09 0 0 0-181.73 71.91 116.12 116.12 0 0 0 2.66 24c-87.28-4.3-164.73-46.3-216.56-109.82A105.48 105.48 0 0 0 68 159.6a106.27 106.27 0 0 1-47.53-13.11v1.43a105.28 105.28 0 0 0 84.21 103.06 105.67 105.67 0 0 1-47.33 1.84 105.06 105.06 0 0 0 98.14 72.94A210.72 210.72 0 0 1 25 370.84a202.17 202.17 0 0 1-25-1.43 298.85 298.85 0 0 0 160.83 46.92" fill="currentColor"/></svg>
</a>
</li>
<li class="nav-item">
<a class="nav-link p-2" href="https://bootstrap-slack.herokuapp.com" target="_blank" rel="noopener" aria-label="Slack">
<svg class="navbar-nav-svg" xmlns="http://www.w3.org/2000/svg" viewbox="0 0 512 512" focusable="false"><title>Slack</title><path fill="currentColor" d="M210.787 234.832l68.31-22.883 22.1 65.977-68.309 22.882z"/><path d="M490.54 185.6C437.7 9.59 361.6-31.34 185.6 21.46S-31.3 150.4 21.46 326.4 150.4 543.3 326.4 490.54 543.34 361.6 490.54 185.6zM401.7 299.8l-33.15 11.05 11.46 34.38c4.5 13.92-2.87 29.06-16.78 33.56-2.87.82-6.14 1.64-9 1.23a27.32 27.32 0 0 1-24.56-18l-11.46-34.38-68.36 22.92 11.46 34.38c4.5 13.92-2.87 29.06-16.78 33.56-2.87.82-6.14 1.64-9 1.23a27.32 27.32 0 0 1-24.56-18l-11.46-34.43-33.15 11.05c-2.87.82-6.14 1.64-9 1.23a27.32 27.32 0 0 1-24.56-18c-4.5-13.92 2.87-29.06 16.78-33.56l33.12-11.03-22.1-65.9-33.15 11.05c-2.87.82-6.14 1.64-9 1.23a27.32 27.32 0 0 1-24.56-18c-4.48-13.93 2.89-29.07 16.81-33.58l33.15-11.05-11.46-34.38c-4.5-13.92 2.87-29.06 16.78-33.56s29.06 2.87 33.56 16.78l11.46 34.38 68.36-22.92-11.46-34.38c-4.5-13.92 2.87-29.06 16.78-33.56s29.06 2.87 33.56 16.78l11.47 34.42 33.15-11.05c13.92-4.5 29.06 2.87 33.56 16.78s-2.87 29.06-16.78 33.56L329.7 194.6l22.1 65.9 33.15-11.05c13.92-4.5 29.06 2.87 33.56 16.78s-2.88 29.07-16.81 33.57z" fill="currentColor"/></svg>
</a>
</li>
</ul>
<a class="btn btn-bd-yellow d-none d-lg-inline-block mb-3 mb-md-0 ml-md-3" href="https://github.com/twbs/bootstrap/archive/v4.0.0-beta.zip">Download</a>
</header>
<div class="container-fluid">
<div class="row flex-xl-nowrap">
<div class="col-12 col-md-3 col-xl-2 bd-sidebar">
<form class="bd-search d-flex align-items-center">
<input type="search" class="form-control" id="search-input" placeholder="Search..." aria-label="Search for..." autocomplete="off">
<button class="btn-link bd-search-docs-toggle d-md-none p-0 ml-3" type="button" data-toggle="collapse" data-target="#bd-docs-nav" aria-controls="bd-docs-nav" aria-expanded="false" aria-label="Toggle docs avigation">
<svg class="" xmlns="http://www.w3.org/2000/svg" viewbox="0 0 30 30" width="30" height="30" focusable="false"><title>Menu</title><path stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-miterlimit="10" d="M4 7h22M4 15h22M4 23h22"/></svg>
</button>
</form>
<nav class="collapse bd-links" id="bd-docs-nav">
<div class="bd-toc-item ">
<a class="bd-toc-link" href="/docs/4.0/getting-started/introduction/">
Getting started
</a>
<ul class="nav bd-sidenav">
<li class="">
<a href="/docs/4.0/getting-started/introduction/">
Introduction
</a>
</li>
<li class="">
<a href="/docs/4.0/getting-started/download/">
Download
</a>
</li>
<li class="">
<a href="/docs/4.0/getting-started/contents/">
Contents
</a>
</li>
<li class="">
<a href="/docs/4.0/getting-started/browsers-devices/">
Browsers & devices
</a>
</li>
<li class="">
<a href="/docs/4.0/getting-started/javascript/">
JavaScript
</a>
</li>
<li class="">
<a href="/docs/4.0/getting-started/options/">
Options
</a>
</li>
<li class="">
<a href="/docs/4.0/getting-started/build-tools/">
Build tools
</a>
</li>
<li class="">
<a href="/docs/4.0/getting-started/webpack/">
Webpack
</a>
</li>
<li class="">
<a href="/docs/4.0/getting-started/accessibility/">
Accessibility
</a>
</li>
</ul>
</div>
<div class="bd-toc-item active">
<a class="bd-toc-link" href="/docs/4.0/layout/overview/">
Layout
</a>
<ul class="nav bd-sidenav">
<li class="active bd-sidenav-active">
<a href="/docs/4.0/layout/overview/">
Overview
</a>
</li>
<li class="">
<a href="/docs/4.0/layout/grid/">
Grid
</a>
</li>
<li class="">
<a href="/docs/4.0/layout/media-object/">
Media object
</a>
</li>
<li class="">
<a href="/docs/4.0/layout/utilities-for-layout/">
Utilities for layout
</a>
</li>
</ul>
</div>
<div class="bd-toc-item ">
<a class="bd-toc-link" href="/docs/4.0/content/reboot/">
Content
</a>
<ul class="nav bd-sidenav">
<li class="">
<a href="/docs/4.0/content/reboot/">
Reboot
</a>
</li>
<li class="">
<a href="/docs/4.0/content/typography/">
Typography
</a>
</li>
<li class="">
<a href="/docs/4.0/content/code/">
Code
</a>
</li>
<li class="">
<a href="/docs/4.0/content/images/">
Images
</a>
</li>
<li class="">
<a href="/docs/4.0/content/tables/">
Tables
</a>
</li>
<li class="">
<a href="/docs/4.0/content/figures/">
Figures
</a>
</li>
</ul>
</div>
<div class="bd-toc-item ">
<a class="bd-toc-link" href="/docs/4.0/components/alerts/">
Components
</a>
<ul class="nav bd-sidenav">
<li class="">
<a href="/docs/4.0/components/alerts/">
Alerts
</a>
</li>
<li class="">
<a href="/docs/4.0/components/badge/">
Badge
</a>
</li>
<li class="">
<a href="/docs/4.0/components/breadcrumb/">
Breadcrumb
</a>
</li>
<li class="">
<a href="/docs/4.0/components/buttons/">
Buttons
</a>
</li>
<li class="">
<a href="/docs/4.0/components/button-group/">
Button group
</a>
</li>
<li class="">
<a href="/docs/4.0/components/card/">
Card
</a>
</li>
<li class="">
<a href="/docs/4.0/components/carousel/">
Carousel
</a>
</li>
<li class="">
<a href="/docs/4.0/components/collapse/">
Collapse
</a>
</li>
<li class="">
<a href="/docs/4.0/components/dropdowns/">
Dropdowns
</a>
</li>
<li class="">
<a href="/docs/4.0/components/forms/">
Forms
</a>
</li>
<li class="">
<a href="/docs/4.0/components/input-group/">
Input group
</a>
</li>
<li class="">
<a href="/docs/4.0/components/jumbotron/">
Jumbotron
</a>
</li>
<li class="">
<a href="/docs/4.0/components/list-group/">
List group
</a>
</li>
<li class="">
<a href="/docs/4.0/components/modal/">
Modal
</a>
</li>
<li class="">
<a href="/docs/4.0/components/navs/">
Navs
</a>
</li>
<li class="">
<a href="/docs/4.0/components/navbar/">
Navbar
</a>
</li>
<li class="">
<a href="/docs/4.0/components/pagination/">
Pagination
</a>
</li>
<li class="">
<a href="/docs/4.0/components/popovers/">
Popovers
</a>
</li>
<li class="">
<a href="/docs/4.0/components/progress/">
Progress
</a>
</li>
<li class="">
<a href="/docs/4.0/components/scrollspy/">
Scrollspy
</a>
</li>
<li class="">
<a href="/docs/4.0/components/tooltips/">
Tooltips
</a>
</li>
</ul>
</div>
<div class="bd-toc-item ">
<a class="bd-toc-link" href="/docs/4.0/utilities/borders/">
Utilities
</a>
<ul class="nav bd-sidenav">
<li class="">
<a href="/docs/4.0/utilities/borders/">
Borders
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/clearfix/">
Clearfix
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/close-icon/">
Close icon
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/colors/">
Colors
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/display/">
Display
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/embed/">
Embed
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/flex/">
Flex
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/float/">
Float
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/image-replacement/">
Image replacement
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/position/">
Position
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/screenreaders/">
Screenreaders
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/sizing/">
Sizing
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/spacing/">
Spacing
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/text/">
Text
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/vertical-align/">
Vertical align
</a>
</li>
<li class="">
<a href="/docs/4.0/utilities/visibility/">
Visibility
</a>
</li>
</ul>
</div>
<div class="bd-toc-item ">
<a class="bd-toc-link" href="/docs/4.0/extend/icons/">
Extend
</a>
<ul class="nav bd-sidenav">
<li class="">
<a href="/docs/4.0/extend/icons/">
Icons
</a>
</li>
</ul>
</div>
<div class="bd-toc-item ">
<a class="bd-toc-link" href="/docs/4.0/migration/">
Migration
</a>
<ul class="nav bd-sidenav">
</ul>
</div>
</nav>
</div>
<div class="d-none d-xl-block col-xl-2 bd-toc">
<ul class="section-nav">
<li class="toc-entry toc-h2"><a href="#containers">Containers</a></li>
<li class="toc-entry toc-h2"><a href="#responsive-breakpoints">Responsive breakpoints</a></li>
<li class="toc-entry toc-h2"><a href="#z-index">Z-index</a></li>
</ul>
</div>
<main class="col-12 col-md-9 col-xl-8 py-md-3 pl-md-5 bd-content" role="main">
<h1 class="bd-title" id="content">Overview</h1>
<p class="bd-lead">Components and options for laying out your Bootstrap project, including wrapping containers, a powerful grid system, a flexible media object, and responsive utility classes.</p>
<script async type="text/javascript" src="https://cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=getbootstrapcom" id="_carbonads_js"></script>
<h2 id="containers">Containers</h2>
<p>Containers are the most basic layout element in Bootstrap and are <strong>required when using our default grid system</strong>. Choose from a responsive, fixed-width container (meaning its <code class="highlighter-rouge">max-width</code> changes at each breakpoint) or fluid-width (meaning its <code class="highlighter-rouge">100%</code> wide all the time).</p>
<p>While containers <em>can</em> be nested, most layouts do not require a nested container.</p>
<div class="bd-example">
<div class="bd-example-container">
<div class="bd-example-container-header"></div>
<div class="bd-example-container-sidebar"></div>
<div class="bd-example-container-body"></div>
</div>
</div>
<figure class="highlight"><pre><code class="language-html" data-lang="html"><span class="nt">&lt;div</span> <span class="na">class=</span><span class="s">"container"</span><span class="nt">&gt;</span>
<span class="c">&lt;!-- Content here --&gt;</span>
<span class="nt">&lt;/div&gt;</span></code></pre></figure>
<p>Use <code class="highlighter-rouge">.container-fluid</code> for a full width container, spanning the entire width of the viewport.</p>
<div class="bd-example">
<div class="bd-example-container bd-example-container-fluid">
<div class="bd-example-container-header"></div>
<div class="bd-example-container-sidebar"></div>
<div class="bd-example-container-body"></div>
</div>
</div>
<figure class="highlight"><pre><code class="language-html" data-lang="html"><span class="nt">&lt;div</span> <span class="na">class=</span><span class="s">"container-fluid"</span><span class="nt">&gt;</span>
...
<span class="nt">&lt;/div&gt;</span></code></pre></figure>
<h2 id="responsive-breakpoints">Responsive breakpoints</h2>
<p>Since Bootstrap is developed to be mobile first, we use a handful of <a href="https://developer.mozilla.org/en-US/docs/Web/CSS/Media_Queries/Using_media_queries">media queries</a> to create sensible breakpoints for our layouts and interfaces. These breakpoints are mostly based on minimum viewport widths and allow us to scale up elements as the viewport changes.</p>
<p>Bootstrap primarily uses the following media query ranges—or breakpoints—in our source Sass files for our layout, grid system, and components.</p>
<figure class="highlight"><pre><code class="language-scss" data-lang="scss"><span class="c1">// Extra small devices (portrait phones, less than 576px)
// No media query since this is the default in Bootstrap
</span>
<span class="c1">// Small devices (landscape phones, 576px and up)
</span><span class="k">@media</span> <span class="p">(</span><span class="n">min-width</span><span class="o">:</span> <span class="m">576px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="c1">// Medium devices (tablets, 768px and up)
</span><span class="k">@media</span> <span class="p">(</span><span class="n">min-width</span><span class="o">:</span> <span class="m">768px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="c1">// Large devices (desktops, 992px and up)
</span><span class="k">@media</span> <span class="p">(</span><span class="n">min-width</span><span class="o">:</span> <span class="m">992px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="c1">// Extra large devices (large desktops, 1200px and up)
</span><span class="k">@media</span> <span class="p">(</span><span class="n">min-width</span><span class="o">:</span> <span class="m">1200px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span></code></pre></figure>
<p>Since we write our source CSS in Sass, all our media queries are available via Sass mixins:</p>
<figure class="highlight"><pre><code class="language-scss" data-lang="scss"><span class="k">@include</span> <span class="nd">media-breakpoint-up</span><span class="p">(</span><span class="n">xs</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="k">@include</span> <span class="nd">media-breakpoint-up</span><span class="p">(</span><span class="n">sm</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="k">@include</span> <span class="nd">media-breakpoint-up</span><span class="p">(</span><span class="n">md</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="k">@include</span> <span class="nd">media-breakpoint-up</span><span class="p">(</span><span class="n">lg</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="k">@include</span> <span class="nd">media-breakpoint-up</span><span class="p">(</span><span class="n">xl</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="c1">// Example usage:
</span><span class="k">@include</span> <span class="nd">media-breakpoint-up</span><span class="p">(</span><span class="n">sm</span><span class="p">)</span> <span class="p">{</span>
<span class="nc">.some-class</span> <span class="p">{</span>
<span class="nl">display</span><span class="p">:</span> <span class="nb">block</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">}</span></code></pre></figure>
<p>We occasionally use media queries that go in the other direction (the given screen size <em>or smaller</em>):</p>
<figure class="highlight"><pre><code class="language-scss" data-lang="scss"><span class="c1">// Extra small devices (portrait phones, less than 576px)
</span><span class="k">@media</span> <span class="p">(</span><span class="n">max-width</span><span class="o">:</span> <span class="m">575px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="c1">// Small devices (landscape phones, less than 768px)
</span><span class="k">@media</span> <span class="p">(</span><span class="n">max-width</span><span class="o">:</span> <span class="m">767px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="c1">// Medium devices (tablets, less than 992px)
</span><span class="k">@media</span> <span class="p">(</span><span class="n">max-width</span><span class="o">:</span> <span class="m">991px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="c1">// Large devices (desktops, less than 1200px)
</span><span class="k">@media</span> <span class="p">(</span><span class="n">max-width</span><span class="o">:</span> <span class="m">1199px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="c1">// Extra large devices (large desktops)
</span><span class="o">//</span> <span class="nt">No</span> <span class="nt">media</span> <span class="nt">query</span> <span class="nt">since</span> <span class="nt">the</span> <span class="nt">extra-large</span> <span class="nt">breakpoint</span> <span class="nt">has</span> <span class="nt">no</span> <span class="nt">upper</span> <span class="nt">bound</span> <span class="nt">on</span> <span class="nt">its</span> <span class="nt">width</span></code></pre></figure>
<p>Once again, these media queries are also available via Sass mixins:</p>
<figure class="highlight"><pre><code class="language-scss" data-lang="scss"><span class="k">@include</span> <span class="nd">media-breakpoint-down</span><span class="p">(</span><span class="n">xs</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="k">@include</span> <span class="nd">media-breakpoint-down</span><span class="p">(</span><span class="n">sm</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="k">@include</span> <span class="nd">media-breakpoint-down</span><span class="p">(</span><span class="n">md</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="k">@include</span> <span class="nd">media-breakpoint-down</span><span class="p">(</span><span class="n">lg</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span></code></pre></figure>
<p>There are also media queries and mixins for targeting a single segment of screen sizes using the minimum and maximum breakpoint widths.</p>
<figure class="highlight"><pre><code class="language-scss" data-lang="scss"><span class="c1">// Extra small devices (portrait phones, less than 576px)
</span><span class="k">@media</span> <span class="p">(</span><span class="n">max-width</span><span class="o">:</span> <span class="m">575px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="c1">// Small devices (landscape phones, 576px and up)
</span><span class="k">@media</span> <span class="p">(</span><span class="n">min-width</span><span class="o">:</span> <span class="m">576px</span><span class="p">)</span> <span class="nf">and</span> <span class="p">(</span><span class="n">max-width</span><span class="o">:</span> <span class="m">767px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="c1">// Medium devices (tablets, 768px and up)
</span><span class="k">@media</span> <span class="p">(</span><span class="n">min-width</span><span class="o">:</span> <span class="m">768px</span><span class="p">)</span> <span class="nf">and</span> <span class="p">(</span><span class="n">max-width</span><span class="o">:</span> <span class="m">991px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="c1">// Large devices (desktops, 992px and up)
</span><span class="k">@media</span> <span class="p">(</span><span class="n">min-width</span><span class="o">:</span> <span class="m">992px</span><span class="p">)</span> <span class="nf">and</span> <span class="p">(</span><span class="n">max-width</span><span class="o">:</span> <span class="m">1199px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="c1">// Extra large devices (large desktops, 1200px and up)
</span><span class="k">@media</span> <span class="p">(</span><span class="n">min-width</span><span class="o">:</span> <span class="m">1200px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span></code></pre></figure>
<p>These media queries are also available via Sass mixins:</p>
<figure class="highlight"><pre><code class="language-scss" data-lang="scss"><span class="k">@include</span> <span class="nd">media-breakpoint-only</span><span class="p">(</span><span class="n">xs</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="k">@include</span> <span class="nd">media-breakpoint-only</span><span class="p">(</span><span class="n">sm</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="k">@include</span> <span class="nd">media-breakpoint-only</span><span class="p">(</span><span class="n">md</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="k">@include</span> <span class="nd">media-breakpoint-only</span><span class="p">(</span><span class="n">lg</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span>
<span class="k">@include</span> <span class="nd">media-breakpoint-only</span><span class="p">(</span><span class="n">xl</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span></code></pre></figure>
<p>Similarly, media queries may span multiple breakpoint widths:</p>
<figure class="highlight"><pre><code class="language-scss" data-lang="scss"><span class="c1">// Example
// Apply styles starting from medium devices and up to extra large devices
</span><span class="k">@media</span> <span class="p">(</span><span class="n">min-width</span><span class="o">:</span> <span class="m">768px</span><span class="p">)</span> <span class="nf">and</span> <span class="p">(</span><span class="n">max-width</span><span class="o">:</span> <span class="m">1199px</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span></code></pre></figure>
<p>The Sass mixin for targeting the same screen size range would be:</p>
<figure class="highlight"><pre><code class="language-scss" data-lang="scss"><span class="k">@include</span> <span class="nd">media-breakpoint-between</span><span class="p">(</span><span class="n">md</span><span class="o">,</span> <span class="n">xl</span><span class="p">)</span> <span class="p">{</span> <span class="nc">...</span> <span class="p">}</span></code></pre></figure>
<h2 id="z-index">Z-index</h2>
<p>Several Bootstrap components utilize <code class="highlighter-rouge">z-index</code>, the CSS property that helps control layout by providing a third axis to arrange content. We utilize a default z-index scale in Bootstrap thats been designed to properly layer navigation, tooltips and popovers, modals, and more.</p>
<p>We dont encourage customization of these values; should you change one, you likely need to change them all.</p>
<div class="language-scss highlighter-rouge"><pre class="highlight"><code><span class="nv">$zindex-dropdown-backdrop</span><span class="p">:</span> <span class="m">990</span> <span class="o">!</span><span class="nb">default</span><span class="p">;</span>
<span class="nv">$zindex-dropdown</span><span class="p">:</span> <span class="m">1000</span> <span class="o">!</span><span class="nb">default</span><span class="p">;</span>
<span class="nv">$zindex-fixed</span><span class="p">:</span> <span class="m">1030</span> <span class="o">!</span><span class="nb">default</span><span class="p">;</span>
<span class="nv">$zindex-sticky</span><span class="p">:</span> <span class="m">1030</span> <span class="o">!</span><span class="nb">default</span><span class="p">;</span>
<span class="nv">$zindex-modal-backdrop</span><span class="p">:</span> <span class="m">1040</span> <span class="o">!</span><span class="nb">default</span><span class="p">;</span>
<span class="nv">$zindex-modal</span><span class="p">:</span> <span class="m">1050</span> <span class="o">!</span><span class="nb">default</span><span class="p">;</span>
<span class="nv">$zindex-popover</span><span class="p">:</span> <span class="m">1060</span> <span class="o">!</span><span class="nb">default</span><span class="p">;</span>
<span class="nv">$zindex-tooltip</span><span class="p">:</span> <span class="m">1070</span> <span class="o">!</span><span class="nb">default</span><span class="p">;</span>
</code></pre>
</div>
<p>Background elements—like the backdrops that allow click-dismissing—tend to reside on a lower <code class="highlighter-rouge">z-index</code>s, while navigation and popovers utilize higher <code class="highlighter-rouge">z-index</code>s to ensure they overlay surrounding content.</p>
</main>
</div>
</div>
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script>window.jQuery || document.write('<script src="/assets/js/vendor/jquery-slim.min.js"><\/script>')</script>
<script src="/assets/js/vendor/popper.min.js"></script>
<script src="/dist/js/bootstrap.min.js"></script>
<script src="/assets/js/docs.min.js"></script>
<!-- IE10 viewport hack for Surface/desktop Windows 8 bug -->
<script src="/assets/js/ie10-viewport-bug-workaround.js"></script>
<script src="/assets/js/ie-emulation-modes-warning.js"></script>
<script type="text/javascript" src="https://cdn.jsdelivr.net/docsearch.js/2/docsearch.min.js"></script>
<script type="text/javascript">
var docsearch = docsearch({
apiKey: '48cb48b22351bc71ea5f12f4d1ede198',
indexName: 'bootstrap-v4',
inputSelector: '#search-input',
handleSelected: function (input, event, suggestion) {
var url = suggestion.url;
url = suggestion.isLvl1 ? url.split('#')[0]: url;
// If it's a title we remove the anchor so it does not jump.
window.location.href = url;
},
transformData: function (hits) {
return hits.map(function (hit) {
hit.url = hit.url.replace('https://v4-alpha.getbootstrap.com', '/docs/4.0');
return hit;
});
},
debug: false // Set debug to true if you want to inspect the dropdown
});
</script>
<script>
Holder.addTheme('gray', {
bg: '#777',
fg: 'rgba(255,255,255,.75)',
font: 'Helvetica',
fontweight: 'normal'
})
</script>
</body>
</html>