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Bootstrap/docs/4.0/components/navbar.md
Mark Otto 9f5f51d871 Close #25697
Removes the .justify-content-between from a navbar form example given it's the default style. Instead, mention how to adjust this and link to flex utils.
2018-03-31 22:02:02 -07:00

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---
layout: docs
title: Navbar
description: Documentation and examples for Bootstrap's powerful, responsive navigation header, the navbar. Includes support for branding, navigation, and more, including support for our collapse plugin.
group: components
toc: true
---
## How it works
Here's what you need to know before getting started with the navbar:
- Navbars require a wrapping `.navbar` with `.navbar-expand{-sm|-md|-lg|-xl}` for responsive collapsing and [color scheme](#color-schemes) classes.
- Navbars and their contents are fluid by default. Use [optional containers](#containers) to limit their horizontal width.
- Use our [spacing]({{ site.baseurl }}/docs/{{ site.docs_version }}/utilities/spacing/) and [flex]({{ site.baseurl }}/docs/{{ site.docs_version }}/utilities/flex/) utility classes for controlling spacing and alignment within navbars.
- Navbars are responsive by default, but you can easily modify them to change that. Responsive behavior depends on our Collapse JavaScript plugin.
- Navbars are hidden by default when printing. Force them to be printed by adding `.d-print` to the `.navbar`. See the [display]({{ site.baseurl }}/docs/{{ site.docs_version }}/utilities/display/) utility class.
- Ensure accessibility by using a `<nav>` element or, if using a more generic element such as a `<div>`, add a `role="navigation"` to every navbar to explicitly identify it as a landmark region for users of assistive technologies.
Read on for an example and list of supported sub-components.
## Supported content
Navbars come with built-in support for a handful of sub-components. Choose from the following as needed:
- `.navbar-brand` for your company, product, or project name.
- `.navbar-nav` for a full-height and lightweight navigation (including support for dropdowns).
- `.navbar-toggler` for use with our collapse plugin and other [navigation toggling](#responsive-behaviors) behaviors.
- `.form-inline` for any form controls and actions.
- `.navbar-text` for adding vertically centered strings of text.
- `.collapse.navbar-collapse` for grouping and hiding navbar contents by a parent breakpoint.
Here's an example of all the sub-components included in a responsive light-themed navbar that automatically collapses at the `lg` (large) breakpoint.
{% capture example %}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarSupportedContent">
<ul class="navbar-nav mr-auto">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Link</a>
</li>
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Dropdown
</a>
<div class="dropdown-menu" aria-labelledby="navbarDropdown">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Something else here</a>
</div>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#">Disabled</a>
</li>
</ul>
<form class="form-inline my-2 my-lg-0">
<input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
</form>
</div>
</nav>
{% endcapture %}
{% include example.html content=example %}
This example uses [color]({{ site.baseurl }}/docs/{{ site.docs_version }}/utilities/colors/) (`bg-light`) and [spacing]({{ site.baseurl }}/docs/{{ site.docs_version }}/utilities/spacing/) (`my-2`, `my-lg-0`, `mr-sm-0`, `my-sm-0`) utility classes.
### Brand
The `.navbar-brand` can be applied to most elements, but an anchor works best as some elements might require utility classes or custom styles.
{% capture example %}
<!-- As a link -->
<nav class="navbar navbar-light bg-light">
<a class="navbar-brand" href="#">Navbar</a>
</nav>
<!-- As a heading -->
<nav class="navbar navbar-light bg-light">
<span class="navbar-brand mb-0 h1">Navbar</span>
</nav>
{% endcapture %}
{% include example.html content=example %}
Adding images to the `.navbar-brand` will likely always require custom styles or utilities to properly size. Here are some examples to demonstrate.
{% capture example %}
<!-- Just an image -->
<nav class="navbar navbar-light bg-light">
<a class="navbar-brand" href="#">
<img src="{{ site.baseurl }}/assets/brand/bootstrap-solid.svg" width="30" height="30" alt="">
</a>
</nav>
{% endcapture %}
{% include example.html content=example %}
{% capture example %}
<!-- Image and text -->
<nav class="navbar navbar-light bg-light">
<a class="navbar-brand" href="#">
<img src="{{ site.baseurl }}/assets/brand/bootstrap-solid.svg" width="30" height="30" class="d-inline-block align-top" alt="">
Bootstrap
</a>
</nav>
{% endcapture %}
{% include example.html content=example %}
### Nav
Navbar navigation links build on our `.nav` options with their own modifier class and require the use of [toggler classes](#toggler) for proper responsive styling. **Navigation in navbars will also grow to occupy as much horizontal space as possible** to keep your navbar contents securely aligned.
Active states—with `.active`—to indicate the current page can be applied directly to `.nav-link`s or their immediate parent `.nav-item`s.
{% capture example %}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarNav">
<ul class="navbar-nav">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Features</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Pricing</a>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#">Disabled</a>
</li>
</ul>
</div>
</nav>
{% endcapture %}
{% include example.html content=example %}
And because we use classes for our navs, you can avoid the list-based approach entirely if you like.
{% capture example %}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNavAltMarkup" aria-controls="navbarNavAltMarkup" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarNavAltMarkup">
<div class="navbar-nav">
<a class="nav-item nav-link active" href="#">Home <span class="sr-only">(current)</span></a>
<a class="nav-item nav-link" href="#">Features</a>
<a class="nav-item nav-link" href="#">Pricing</a>
<a class="nav-item nav-link disabled" href="#">Disabled</a>
</div>
</div>
</nav>
{% endcapture %}
{% include example.html content=example %}
You may also utilize dropdowns in your navbar nav. Dropdown menus require a wrapping element for positioning, so be sure to use separate and nested elements for `.nav-item` and `.nav-link` as shown below.
{% capture example %}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNavDropdown" aria-controls="navbarNavDropdown" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarNavDropdown">
<ul class="navbar-nav">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Features</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Pricing</a>
</li>
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" id="navbarDropdownMenuLink" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Dropdown link
</a>
<div class="dropdown-menu" aria-labelledby="navbarDropdownMenuLink">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
</div>
</li>
</ul>
</div>
</nav>
{% endcapture %}
{% include example.html content=example %}
### Forms
Place various form controls and components within a navbar with `.form-inline`.
{% capture example %}
<nav class="navbar navbar-light bg-light">
<form class="form-inline">
<input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
</form>
</nav>
{% endcapture %}
{% include example.html content=example %}
Immediate children elements in `.navbar` use flex layout and will default to `justify-content: between`. Use additional [flex utilities]({{ site.baseurl }}/docs/{{ site.docs_version }}/utilities/flex/) as needed to adjust this behavior.
{% capture example %}
<nav class="navbar navbar-light bg-light">
<a class="navbar-brand">Navbar</a>
<form class="form-inline">
<input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
</form>
</nav>
{% endcapture %}
{% include example.html content=example %}
Input groups work, too:
{% capture example %}
<nav class="navbar navbar-light bg-light">
<form class="form-inline">
<div class="input-group">
<div class="input-group-prepend">
<span class="input-group-text" id="basic-addon1">@</span>
</div>
<input type="text" class="form-control" placeholder="Username" aria-label="Username" aria-describedby="basic-addon1">
</div>
</form>
</nav>
{% endcapture %}
{% include example.html content=example %}
Various buttons are supported as part of these navbar forms, too. This is also a great reminder that vertical alignment utilities can be used to align different sized elements.
{% capture example %}
<nav class="navbar navbar-light bg-light">
<form class="form-inline">
<button class="btn btn-outline-success" type="button">Main button</button>
<button class="btn btn-sm btn-outline-secondary" type="button">Smaller button</button>
</form>
</nav>
{% endcapture %}
{% include example.html content=example %}
### Text
Navbars may contain bits of text with the help of `.navbar-text`. This class adjusts vertical alignment and horizontal spacing for strings of text.
{% capture example %}
<nav class="navbar navbar-light bg-light">
<span class="navbar-text">
Navbar text with an inline element
</span>
</nav>
{% endcapture %}
{% include example.html content=example %}
Mix and match with other components and utilities as needed.
{% capture example %}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<a class="navbar-brand" href="#">Navbar w/ text</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarText" aria-controls="navbarText" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarText">
<ul class="navbar-nav mr-auto">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Features</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Pricing</a>
</li>
</ul>
<span class="navbar-text">
Navbar text with an inline element
</span>
</div>
</nav>
{% endcapture %}
{% include example.html content=example %}
## Color schemes
Theming the navbar has never been easier thanks to the combination of theming classes and `background-color` utilities. Choose from `.navbar-light` for use with light background colors, or `.navbar-dark` for dark background colors. Then, customize with `.bg-*` utilities.
<div class="bd-example">
<nav class="navbar navbar-expand-lg navbar-dark bg-dark">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarColor01" aria-controls="navbarColor01" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarColor01">
<ul class="navbar-nav mr-auto">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Features</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Pricing</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">About</a>
</li>
</ul>
<form class="form-inline">
<input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-info my-2 my-sm-0" type="submit">Search</button>
</form>
</div>
</nav>
<nav class="navbar navbar-expand-lg navbar-dark bg-primary">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarColor02" aria-controls="navbarColor02" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarColor02">
<ul class="navbar-nav mr-auto">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Features</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Pricing</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">About</a>
</li>
</ul>
<form class="form-inline">
<input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-light my-2 my-sm-0" type="submit">Search</button>
</form>
</div>
</nav>
<nav class="navbar navbar-expand-lg navbar-light" style="background-color: #e3f2fd;">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarColor03" aria-controls="navbarColor03" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarColor03">
<ul class="navbar-nav mr-auto">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Features</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Pricing</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">About</a>
</li>
</ul>
<form class="form-inline">
<input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-primary my-2 my-sm-0" type="submit">Search</button>
</form>
</div>
</nav>
</div>
{% highlight html %}
<nav class="navbar navbar-dark bg-dark">
<!-- Navbar content -->
</nav>
<nav class="navbar navbar-dark bg-primary">
<!-- Navbar content -->
</nav>
<nav class="navbar navbar-light" style="background-color: #e3f2fd;">
<!-- Navbar content -->
</nav>
{% endhighlight %}
## Containers
Although it's not required, you can wrap a navbar in a `.container` to center it on a page or add one within to only center the contents of a [fixed or static top navbar](#placement).
{% capture example %}
<div class="container">
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<a class="navbar-brand" href="#">Navbar</a>
</nav>
</div>
{% endcapture %}
{% include example.html content=example %}
When the container is within your navbar, its horizontal padding is removed at breakpoints lower than your specified `.navbar-expand{-sm|-md|-lg|-xl}` class. This ensures we're not doubling up on padding unnecessarily on lower viewports when your navbar is collapsed.
{% capture example %}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<div class="container">
<a class="navbar-brand" href="#">Navbar</a>
</div>
</nav>
{% endcapture %}
{% include example.html content=example %}
## Placement
Use our [position utilities]({{ site.baseurl }}/docs/{{ site.docs_version }}/utilities/position/) to place navbars in non-static positions. Choose from fixed to the top, fixed to the bottom, or stickied to the top (scrolls with the page until it reaches the top, then stays there). Fixed navbars use `position: fixed`, meaning they're pulled from the normal flow of the DOM and may require custom CSS (e.g., `padding-top` on the `<body>`) to prevent overlap with other elements.
Also note that **`.sticky-top` uses `position: sticky`, which [isn't fully supported in every browser](https://caniuse.com/#feat=css-sticky)**.
{% capture example %}
<nav class="navbar navbar-light bg-light">
<a class="navbar-brand" href="#">Default</a>
</nav>
{% endcapture %}
{% include example.html content=example %}
{% capture example %}
<nav class="navbar fixed-top navbar-light bg-light">
<a class="navbar-brand" href="#">Fixed top</a>
</nav>
{% endcapture %}
{% include example.html content=example %}
{% capture example %}
<nav class="navbar fixed-bottom navbar-light bg-light">
<a class="navbar-brand" href="#">Fixed bottom</a>
</nav>
{% endcapture %}
{% include example.html content=example %}
{% capture example %}
<nav class="navbar sticky-top navbar-light bg-light">
<a class="navbar-brand" href="#">Sticky top</a>
</nav>
{% endcapture %}
{% include example.html content=example %}
## Responsive behaviors
Navbars can utilize `.navbar-toggler`, `.navbar-collapse`, and `.navbar-expand{-sm|-md|-lg|-xl}` classes to change when their content collapses behind a button. In combination with other utilities, you can easily choose when to show or hide particular elements.
For navbars that never collapse, add the `.navbar-expand` class on the navbar. For navbars that always collapse, don't add any `.navbar-expand` class.
### Toggler
Navbar togglers are left-aligned by default, but should they follow a sibling element like a `.navbar-brand`, they'll automatically be aligned to the far right. Reversing your markup will reverse the placement of the toggler. Below are examples of different toggle styles.
With no `.navbar-brand` shown in lowest breakpoint:
{% capture example %}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarTogglerDemo01" aria-controls="navbarTogglerDemo01" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarTogglerDemo01">
<a class="navbar-brand" href="#">Hidden brand</a>
<ul class="navbar-nav mr-auto mt-2 mt-lg-0">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Link</a>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#">Disabled</a>
</li>
</ul>
<form class="form-inline my-2 my-lg-0">
<input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
</form>
</div>
</nav>
{% endcapture %}
{% include example.html content=example %}
With a brand name shown on the left and toggler on the right:
{% capture example %}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarTogglerDemo02" aria-controls="navbarTogglerDemo02" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarTogglerDemo02">
<ul class="navbar-nav mr-auto mt-2 mt-lg-0">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Link</a>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#">Disabled</a>
</li>
</ul>
<form class="form-inline my-2 my-lg-0">
<input class="form-control mr-sm-2" type="search" placeholder="Search">
<button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
</form>
</div>
</nav>
{% endcapture %}
{% include example.html content=example %}
With a toggler on the left and brand name on the right:
{% capture example %}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarTogglerDemo03" aria-controls="navbarTogglerDemo03" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<a class="navbar-brand" href="#">Navbar</a>
<div class="collapse navbar-collapse" id="navbarTogglerDemo03">
<ul class="navbar-nav mr-auto mt-2 mt-lg-0">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Link</a>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#">Disabled</a>
</li>
</ul>
<form class="form-inline my-2 my-lg-0">
<input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
</form>
</div>
</nav>
{% endcapture %}
{% include example.html content=example %}
### External content
Sometimes you want to use the collapse plugin to trigger hidden content elsewhere on the page. Because our plugin works on the `id` and `data-target` matching, that's easily done!
{% capture example %}
<div class="pos-f-t">
<div class="collapse" id="navbarToggleExternalContent">
<div class="bg-dark p-4">
<h4 class="text-white">Collapsed content</h4>
<span class="text-muted">Toggleable via the navbar brand.</span>
</div>
</div>
<nav class="navbar navbar-dark bg-dark">
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarToggleExternalContent" aria-controls="navbarToggleExternalContent" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
</nav>
</div>
{% endcapture %}
{% include example.html content=example %}