Nav

Add lists of links to your pages with various navigation components—tabs, pills, underline—and plenty of options to customize.

@layer components

JavaScript is optional

Context tokens

Base nav

Navigation available in Chassis CSS share general markup and styles, from the base .nav class to the active and disabled states. Swap modifier classes to switch between each style.

The base .nav component is built with flexbox and provide a strong foundation for building all types of navigation components. It includes some style overrides (for working with lists), some link padding for larger hit areas, and basic disabled styling.

To convey the active state to assistive technologies, use the aria-current attribute — using the page value for current page, or true for the current item in a set.

<ul class="nav">
  <li class="nav-item">
    <a class="nav-link active" aria-current="page" href="#">Active</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link disabled" aria-disabled="true">Disabled</a>
  </li>
</ul>

Classes are used throughout, so your markup can be super flexible. Use <ul>s like above, <ol> if the order of your items is important, or roll your own with a <nav> element. Because the .nav uses display: flex, the nav links behave the same as nav items would, but without the extra markup.

<nav class="nav" aria-label="Example navigation">
  <a class="nav-link active" aria-current="page" href="#">Active</a>
  <a class="nav-link" href="#">Link</a>
  <a class="nav-link" href="#">Link</a>
  <a class="nav-link disabled" aria-disabled="true">Disabled</a>
</nav>

Where appropriate, you can also use <button> elements instead of <a> elements for the nav links. You can even mix and match—for example, by using buttons for menus.

<nav class="nav" aria-label="Example navigation with menu">
  <a class="nav-link active" aria-current="page" href="#">Active</a>
  <a class="nav-link" href="#">Link</a>
  <button type="button" class="nav-link" data-cx-toggle="menu" aria-expanded="false">Menu</button>
  <div class="menu">
    <a class="menu-item" href="#">Action</a>
    <a class="menu-item" href="#">Another action</a>
    <hr class="menu-divider">
    <a class="menu-item" href="#">Something else here</a>
  </div>
  <a class="nav-link disabled" aria-disabled="true">Disabled</a>
</nav>

Tab JavaScript plugin

Use the tab JavaScript plugin to create tabbable regions.

Available styles

Change the style of .navs component with modifiers and utilities. Mix and match as needed, or build your own.

Tabs

Takes the basic nav from above and adds the .nav-tabs class to generate a tabbed interface.

<ul class="nav nav-tabs">
  <li class="nav-item">
    <a class="nav-link active" aria-current="page" href="#">Active</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link disabled" aria-disabled="true">Disabled</a>
  </li>
</ul>

Pills

Take that same HTML, but use .nav-pills instead for a more themed appearance.

<ul class="nav nav-pills">
  <li class="nav-item">
    <a class="nav-link active" aria-current="page" href="#">Active</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link disabled" aria-disabled="true">Disabled</a>
  </li>
</ul>

Pill navigation can also go vertical with an additional modifier class, .nav-pills-vertical.

<ul class="nav nav-pills nav-pills-vertical">
  <li class="nav-item">
    <a class="nav-link active" aria-current="page" href="#">Active</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link disabled" aria-disabled="true">Disabled</a>
  </li>
</ul>

Underline

Take that same HTML, but use .nav-underline instead:

<ul class="nav nav-underline">
  <li class="nav-item">
    <a class="nav-link active" aria-current="page" href="#">Active</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link disabled" aria-disabled="true">Disabled</a>
  </li>
</ul>

Alignment

Change the alignment of your nav with flexbox utilities. By default, navs are horizontal and left-aligned, but you can easily modify them to center or right-aligned, and even stacked vertically.

Horizontal

Centered with .justify-content-center:

<ul class="nav justify-content-center">
  <li class="nav-item">
    <a class="nav-link active" aria-current="page" href="#">Active</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link disabled" aria-disabled="true">Disabled</a>
  </li>
</ul>

Right-aligned with .justify-content-end:

<ul class="nav justify-content-end">
  <li class="nav-item">
    <a class="nav-link active" aria-current="page" href="#">Active</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link disabled" aria-disabled="true">Disabled</a>
  </li>
</ul>

Vertical

Stack your navigation by changing the flex item direction with the .flex-column utility. Need to stack them on some viewports but not others? Use the responsive versions (e.g., .small:flex-column).

<ul class="nav flex-column">
  <li class="nav-item">
    <a class="nav-link active" aria-current="page" href="#">Active</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link disabled" aria-disabled="true">Disabled</a>
  </li>
</ul>

As always, vertical navigation is possible without <ul>s, too.

<nav class="nav flex-column" aria-label="Vertical navigation">
  <a class="nav-link active" aria-current="page" href="#">Active</a>
  <a class="nav-link" href="#">Link</a>
  <a class="nav-link" href="#">Link</a>
  <a class="nav-link disabled" aria-disabled="true">Disabled</a>
</nav>

Working with flex utilities

Fill and justify

Force your .nav's contents to extend the full available width with one of two modifier classes. To proportionately fill all available space with your .nav-items, use .nav-fill. Notice that all horizontal space is occupied, but not every nav item has the same width.

<ul class="nav nav-pills d-flex nav-fill flex-column small:flex-row rounded-3xlarge">
  <li class="nav-item">
    <a class="nav-link active" aria-current="page" href="#">Active</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Much longer nav link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link disabled" aria-disabled="true">Disabled</a>
  </li>
</ul>

When using a <nav>-based navigation, you can safely omit .nav-item as only .nav-link is required for styling <a> elements.

<nav class="nav nav-pills d-flex nav-fill flex-column small:flex-row rounded-3xlarge" aria-label="Fill navigation">
  <a class="nav-link active" aria-current="page" href="#">Active</a>
  <a class="nav-link" href="#">Much longer nav link</a>
  <a class="nav-link" href="#">Link</a>
  <a class="nav-link disabled" aria-disabled="true">Disabled</a>
</nav>

For equal-width elements, use .nav-justified. All horizontal space will be occupied by nav links, but unlike the .nav-fill above, every nav item will be the same width.

<ul class="nav nav-pills d-flex nav-justified flex-column medium:flex-row rounded-3xlarge">
  <li class="nav-item">
    <a class="nav-link active" aria-current="page" href="#">Active</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Much longer nav link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link disabled" aria-disabled="true">Disabled</a>
  </li>
</ul>

Similar to the .nav-fill example using a <nav>-based navigation.

<nav class="nav nav-pills d-flex nav-justified flex-column medium:flex-row rounded-3xlarge" aria-label="Justified navigation">
  <a class="nav-link active" aria-current="page" href="#">Active</a>
  <a class="nav-link" href="#">Much longer nav link</a>
  <a class="nav-link" href="#">Link</a>
  <a class="nav-link disabled" aria-disabled="true">Disabled</a>
</nav>

Using menus

Add menus with a little extra HTML and the menus JavaScript plugin.

Tabs with menus

<ul class="nav nav-tabs">
  <li class="nav-item">
    <a class="nav-link active" aria-current="page" href="#">Active</a>
  </li>
  <li class="nav-item">
    <button type="button" class="nav-link" data-cx-toggle="menu" aria-expanded="false">Menu</button>
    <div class="menu">
      <a class="menu-item" href="#">Action</a>
      <a class="menu-item" href="#">Another action</a>
      <a class="menu-item" href="#">Something else here</a>
      <hr class="menu-divider">
      <a class="menu-item" href="#">Separated link</a>
    </div>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link disabled" aria-disabled="true">Disabled</a>
  </li>
</ul>

Pills with menus

<ul class="nav nav-pills">
  <li class="nav-item">
    <a class="nav-link active" aria-current="page" href="#">Active</a>
  </li>
  <li class="nav-item">
    <button type="button" class="nav-link" data-cx-toggle="menu" aria-expanded="false">Menu</button>
    <div class="menu">
      <a class="menu-item" href="#">Action</a>
      <a class="menu-item" href="#">Another action</a>
      <a class="menu-item" href="#">Something else here</a>
      <hr class="menu-divider">
      <a class="menu-item" href="#">Separated link</a>
    </div>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link disabled" aria-disabled="true">Disabled</a>
  </li>
</ul>

Transform navigation menus into expandable/collapsible sections using the .collapsible class on .nav-item elements.

Use data-cx-toggle="collapse" with the target selector to create the interactive trigger. Proper accessibility is maintained through aria-expanded and aria-controls attributes.

<ul class="nav flex-column">
  <li class="nav-item collapsible border-bottom">
    <a class="nav-link" href="#navCollapse1" data-cx-toggle="collapse" aria-expanded="false" aria-controls="navCollapse1">Collapsed Item</a>
    <div class="collapse" id="navCollapse1">
      <nav class="nav flex-column ps-medium" aria-label="Collapsed Item submenu">
        <a class="nav-link" href="#">Child item 1</a>
        <a class="nav-link" href="#">Child item 2</a>
        <a class="nav-link" href="#">Child item 3</a>
      </nav>
    </div>
  </li>
  <li class="nav-item collapsible">
    <a class="nav-link" href="#navCollapse2" data-cx-toggle="collapse" aria-expanded="true" aria-controls="navCollapse2">Collapsible Item</a>
    <div class="collapse show" id="navCollapse2">
      <nav class="nav flex-column ps-medium" aria-label="Collapsible Item submenu">
        <a class="nav-link" href="#">Child item 1</a>
        <a class="nav-link" href="#">Child item 2</a>
        <a class="nav-link" href="#">Child item 3</a>
      </nav>
    </div>
  </li>
</ul>

For mutually exclusive expandable sections, implement accordion behavior by adding the same data-cx-parent attribute to all .collapse elements within a container. This ensures only one navigation section is expanded at a time, creating a more organized interface for complex navigation hierarchies.

<ul class="nav flex-column" id="navAccordion">
  <li class="nav-item collapsible border-bottom">
    <a class="nav-link" href="#navCollapse3" data-cx-toggle="collapse" aria-expanded="true" aria-controls="navCollapse3">Collapsible Item</a>
    <div class="collapse show" id="navCollapse3" data-cx-parent="#navAccordion">
      <nav class="nav flex-column ps-medium" aria-label="First accordion submenu">
        <a class="nav-link" href="#">Child item 1</a>
        <a class="nav-link" href="#">Child item 2</a>
        <a class="nav-link" href="#">Child item 3</a>
      </nav>
    </div>
  </li>
  <li class="nav-item collapsible collapsed border-bottom">
    <a class="nav-link" href="#navCollapse4" data-cx-toggle="collapse" aria-expanded="false" aria-controls="navCollapse4">Collapsible Item</a>
    <div class="collapse" id="navCollapse4" data-cx-parent="#navAccordion">
      <nav class="nav flex-column ps-medium" aria-label="Second accordion submenu">
        <a class="nav-link" href="#">Child item 1</a>
        <a class="nav-link" href="#">Child item 2</a>
        <a class="nav-link" href="#">Child item 3</a>
      </nav>
    </div>
  </li>
  <li class="nav-item collapsible collapsed">
    <a class="nav-link nav-collapse" href="#navCollapse5" data-cx-toggle="collapse" aria-expanded="false" aria-controls="navCollapse5">Collapsible Item</a>
    <div class="collapse" id="navCollapse5" data-cx-parent="#navAccordion">
      <nav class="nav flex-column ps-medium" aria-label="Third accordion submenu">
        <a class="nav-link" href="#">Child item 1</a>
        <a class="nav-link" href="#">Child item 2</a>
        <a class="nav-link" href="#">Child item 3</a>
      </nav>
    </div>
  </li>
</ul>

See the collapse component page for more details.

Accessibility

If you're using navs to provide a navigation bar, be sure to add a role="navigation" to the most logical parent container of the <ul>, or wrap a <nav> element around the whole navigation. Do not add the role to the <ul> itself, as this would prevent it from being announced as an actual list by assistive technologies.

Note that navigation bars, even if visually styled as tabs with the .nav-tabs class, should not be given role="tablist", role="tab" or role="tabpanel" attributes. These are only appropriate for dynamic tabbed interfaces, as described in the ARIA Authoring Practices Guide tabs pattern. See the Tab plugin for dynamic tabbed interfaces. The aria-current attribute is not necessary on dynamic tabbed interfaces since our JavaScript handles the selected state by adding aria-selected="true" on the active tab.

CSS

Navigation components can be customized through Sass variables at compile time.

Variables

Nav components expose CSS custom properties to control their appearance at runtime.

On the .nav base class:

--link-padding-y: var(--nav-link-padding-y, #{$nav-link-padding-y});
--link-padding-x: var(--nav-link-padding-x, #{$nav-link-padding-x});
--link-border-radius: var(--nav-link-border-radius, #{$nav-link-border-radius});
--link-main-color: var(--nav-link-main-color, #{$nav-link-main-color});
--link-hover-color: var(--nav-link-hover-color, #{$nav-link-hover-color});
--link-hover-bg: var(--nav-link-hover-bg, #{$nav-link-hover-bg});
--link-active-color: var(--nav-link-active-color, #{$nav-link-active-color});
--link-active-bg: var(--nav-link-active-bg, #{$nav-link-active-bg});
--link-disabled-color: var(--nav-link-disabled-color, #{$nav-link-disabled-color});
--caret-spacing: var(--space-2xsmall) 0;

@if $nav-link-font {
  --link-font-family: var(--nav-link-font-family, #{map.get($nav-link-font, font-family)});
  --link-font-weight: var(--nav-link-font-weight, #{map.get($nav-link-font, font-weight)});
  @include clamp(map.get($nav-link-font, font-size), --link-font-size, --nav-link-font-size);
  @include clamp(map.get($nav-link-font, line-height), --link-line-height, --nav-link-line-height);
}

On the .nav-tabs modifier class:

--border-width: var(--nav-tabs-border-width, #{$nav-tabs-border-width});
--border-color: var(--nav-tabs-border-color, #{$nav-tabs-border-color});
--link-border-radius: var(--nav-tabs-border-radius, #{$nav-tabs-border-radius});
--active-fg-color: var(--nav-tabs-active-fg-color, #{$nav-tabs-active-fg-color});
--active-bg-color: var(--nav-tabs-active-bg-color, #{$nav-tabs-active-bg-color});
--active-border-top-color: var(--nav-tabs-active-border-top-color, #{$nav-tabs-active-border-top-color});
--active-border-top-width: var(--nav-tabs-active-border-top-width, #{$nav-tabs-active-border-top-width});

On the .nav-pills modifier class:

--bg-color: var(--nav-pills-bg-color, #{$nav-pills-bg-color});
--padding: var(--nav-pills-padding, #{$nav-pills-padding});
--border-radius: var(--nav-pills-border-radius, #{$nav-pills-border-radius});
--link-border-radius: var(--nav-pills-link-border-radius, #{$nav-pills-link-border-radius});
--active-fg-color: var(--nav-pills-active-fg-color, #{$nav-pills-active-fg-color});
--active-bg-color: var(--nav-pills-active-bg-color, #{$nav-pills-active-bg-color});
--active-box-shadow: var(--nav-pills-active-box-shadow, #{$nav-pills-active-box-shadow});

On the .nav-underline modifier class:

--gap: var(--nav-underline-gap, #{$nav-underline-gap});
--link-padding-x: var(--nav-underline-link-padding-x, #{$nav-underline-link-padding-x});
--border-width: var(--nav-underline-border-width, #{$nav-underline-border-width});
--border-color: var(--nav-underline-border-color, #{$nav-underline-border-color});
--active-fg-color: var(--nav-underline-active-fg-color, #{$nav-underline-active-fg-color});
--active-bg-color: var(--nav-underline-active-bg-color, #{$nav-underline-active-bg-color});
--active-border-width: var(--nav-underline-active-border-width, #{$nav-underline-active-border-width});
--active-border-color: var(--nav-underline-active-border-color, #{$nav-underline-active-border-color});

Nav