Accordion

Build vertically collapsing accordions in combination with our Collapse JavaScript plugin.

On this page

How it works

The accordion uses collapse internally to make it collapsible. To render an accordion that’s expanded, add the .open class on the .accordion.

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

Example

Click the accordions below to expand/collapse the accordion content.

This is the first item's accordion body. It is shown by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the .accordion-body, though the transition does limit overflow.

This is the second item's accordion body. It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the .accordion-body, though the transition does limit overflow.

This is the third item's accordion body. It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the .accordion-body, though the transition does limit overflow.

html

<div class="accordion" id="accordionExample">
  <div class="accordion-item">
    <h2 class="accordion-header" id="headingOne">
      <button class="accordion-button" type="button" data-bs-toggle="collapse" data-bs-target="#collapseOne" aria-expanded="true" aria-controls="collapseOne">
        Accordion Item #1
      </button>
    </h2>
    <div id="collapseOne" class="accordion-collapse collapse show" aria-labelledby="headingOne" data-bs-parent="#accordionExample">
      <div class="accordion-body">
        <strong>This is the first item's accordion body.</strong> It is shown by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
      </div>
    </div>
  </div>
  <div class="accordion-item">
    <h2 class="accordion-header" id="headingTwo">
      <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseTwo" aria-expanded="false" aria-controls="collapseTwo">
        Accordion Item #2
      </button>
    </h2>
    <div id="collapseTwo" class="accordion-collapse collapse" aria-labelledby="headingTwo" data-bs-parent="#accordionExample">
      <div class="accordion-body">
        <strong>This is the second item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
      </div>
    </div>
  </div>
  <div class="accordion-item">
    <h2 class="accordion-header" id="headingThree">
      <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseThree" aria-expanded="false" aria-controls="collapseThree">
        Accordion Item #3
      </button>
    </h2>
    <div id="collapseThree" class="accordion-collapse collapse" aria-labelledby="headingThree" data-bs-parent="#accordionExample">
      <div class="accordion-body">
        <strong>This is the third item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
      </div>
    </div>
  </div>
</div>

Sizes

Add .accordion-lg or .accordion-sm for additional sizes.

This is the first item's accordion body. It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the .accordion-body, though the transition does limit overflow.

html

<div class="row">
  <div class="col-md-6 col-lg-5">
    <div class="accordion accordion-sm" id="accordionExampleSmall">
      <div class="accordion-item">
        <h2 class="accordion-header" id="headingOneSmall">
          <button class="accordion-button" type="button" data-bs-toggle="collapse" data-bs-target="#collapseOneSmall" aria-expanded="true" aria-controls="collapseOneSmall">
            Accordion Item #1
          </button>
        </h2>
        <div id="collapseOneSmall" class="accordion-collapse collapse show" aria-labelledby="headingOneSmall" data-bs-parent="#accordionExampleSmall">
          <div class="accordion-body">
            <strong>This is the first item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
          </div>
        </div>
      </div>
      <div class="accordion-item">
        <h2 class="accordion-header" id="headingTwoSmall">
          <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseTwoSmall" aria-expanded="false" aria-controls="collapseTwoSmall">
            Accordion Item #2
          </button>
        </h2>
        <div id="collapseTwoSmall" class="accordion-collapse collapse" aria-labelledby="headingTwoSmall" data-bs-parent="#accordionExampleSmall">
          <div class="accordion-body">
            <strong>This is the second item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
          </div>
        </div>
      </div>
      <div class="accordion-item">
        <h2 class="accordion-header" id="headingThreeSmall">
          <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseThreeSmall" aria-expanded="false" aria-controls="collapseThreeSmall">
            Accordion Item #3
          </button>
        </h2>
        <div id="collapseThreeSmall" class="accordion-collapse collapse" aria-labelledby="headingThreeSmall" data-bs-parent="#accordionExampleSmall">
          <div class="accordion-body">
            <strong>This is the third item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
          </div>
        </div>
      </div>
    </div>
  </div>
  <div class="col-md-6 col-lg-7">
    <div class="accordion accordion-lg" id="accordionExampleLarge">
      <div class="accordion-item">
        <h2 class="accordion-header" id="headingOneLarge">
          <button class="accordion-button" type="button" data-bs-toggle="collapse" data-bs-target="#collapseOneLarge" aria-expanded="true" aria-controls="collapseOneLarge">
            Accordion Item #1
          </button>
        </h2>
        <div id="collapseOneLarge" class="accordion-collapse collapse show" aria-labelledby="headingOneLarge" data-bs-parent="#accordionExampleLarge">
          <div class="accordion-body">
            <strong>This is the first item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
          </div>
        </div>
      </div>
      <div class="accordion-item">
        <h2 class="accordion-header" id="headingTwoLarge">
          <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseTwoLarge" aria-expanded="false" aria-controls="collapseTwoLarge">
            Accordion Item #2
          </button>
        </h2>
        <div id="collapseTwoLarge" class="accordion-collapse collapse" aria-labelledby="headingTwoLarge" data-bs-parent="#accordionExampleLarge">
          <div class="accordion-body">
            <strong>This is the second item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
          </div>
        </div>
      </div>
      <div class="accordion-item">
        <h2 class="accordion-header" id="headingThreeLarge">
          <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseThreeLarge" aria-expanded="false" aria-controls="collapseThreeLarge">
            Accordion Item #3
          </button>
        </h2>
        <div id="collapseThreeLarge" class="accordion-collapse collapse" aria-labelledby="headingThreeLarge" data-bs-parent="#accordionExampleLarge">
          <div class="accordion-body">
            <strong>This is the third item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
          </div>
        </div>
      </div>
    </div>
  </div>
</div>

Always open

Omit the data-bs-parent attribute on each .accordion-collapse to make accordion items stay open when another item is opened.

html

<div class="accordion" id="accordionPanelsStayOpenExample">
  <div class="accordion-item">
    <h2 class="accordion-header" id="panelsStayOpen-headingOne">
      <button class="accordion-button" type="button" data-bs-toggle="collapse" data-bs-target="#panelsStayOpen-collapseOne" aria-expanded="true" aria-controls="panelsStayOpen-collapseOne">
        Accordion Item #1
      </button>
    </h2>
    <div id="panelsStayOpen-collapseOne" class="accordion-collapse collapse show" aria-labelledby="panelsStayOpen-headingOne">
      <div class="accordion-body">
        <strong>This is the first item's accordion body.</strong> It is shown by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
      </div>
    </div>
  </div>
  <div class="accordion-item">
    <h2 class="accordion-header" id="panelsStayOpen-headingTwo">
      <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#panelsStayOpen-collapseTwo" aria-expanded="false" aria-controls="panelsStayOpen-collapseTwo">
        Accordion Item #2
      </button>
    </h2>
    <div id="panelsStayOpen-collapseTwo" class="accordion-collapse collapse" aria-labelledby="panelsStayOpen-headingTwo">
      <div class="accordion-body">
        <strong>This is the second item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
      </div>
    </div>
  </div>
  <div class="accordion-item">
    <h2 class="accordion-header" id="panelsStayOpen-headingThree">
      <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#panelsStayOpen-collapseThree" aria-expanded="false" aria-controls="panelsStayOpen-collapseThree">
        Accordion Item #3
      </button>
    </h2>
    <div id="panelsStayOpen-collapseThree" class="accordion-collapse collapse" aria-labelledby="panelsStayOpen-headingThree">
      <div class="accordion-body">
        <strong>This is the third item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
      </div>
    </div>
  </div>
</div>

Dark variant

Add .accordion-dark to the .accordion for a dark variant.

html

<div class="accordion accordion-dark" id="accordionPanelsDarkExample">
  <div class="accordion-item">
    <h2 class="accordion-header" id="panelsDark-headingOne">
      <button class="accordion-button" type="button" data-bs-toggle="collapse" data-bs-target="#panelsDark-collapseOne" aria-expanded="true" aria-controls="panelsDark-collapseOne">
        Accordion Item #1
      </button>
    </h2>
    <div id="panelsDark-collapseOne" class="accordion-collapse collapse show" aria-labelledby="panelsDark-headingOne" data-bs-parent="#accordionPanelsDarkExample">
      <div class="accordion-body">
        <strong>This is the first item's accordion body.</strong> It is shown by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
      </div>
    </div>
  </div>
  <div class="accordion-item">
    <h2 class="accordion-header" id="panelsDark-headingTwo">
      <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#panelsDark-collapseTwo" aria-expanded="false" aria-controls="panelsDark-collapseTwo">
        Accordion Item #2
      </button>
    </h2>
    <div id="panelsDark-collapseTwo" class="accordion-collapse collapse" aria-labelledby="panelsDark-headingTwo" data-bs-parent="#accordionPanelsDarkExample">
      <div class="accordion-body">
        <strong>This is the second item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
      </div>
    </div>
  </div>
  <div class="accordion-item">
    <h2 class="accordion-header" id="panelsDark-headingThree">
      <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#panelsDark-collapseThree" aria-expanded="false" aria-controls="panelsDark-collapseThree">
        Accordion Item #3
      </button>
    </h2>
    <div id="panelsDark-collapseThree" class="accordion-collapse collapse" aria-labelledby="panelsDark-headingThree" data-bs-parent="#accordionPanelsDarkExample">
      <div class="accordion-body">
        <strong>This is the third item's accordion body.</strong> It is hidden by default, until the collapse plugin adds the appropriate classes that we use to style each element. These classes control the overall appearance, as well as the showing and hiding via CSS transitions. You can modify any of this with custom CSS or overriding our default variables. It's also worth noting that just about any HTML can go within the <code>.accordion-body</code>, though the transition does limit overflow.
      </div>
    </div>
  </div>
</div>

Accessibility

Please read the collapse accessibility section for more information.

CSS

Variables

As part of Boosted Innovation Cup’s evolving CSS variables approach, accordions now use local CSS variables on .accordion for enhanced real-time customization. Values for the CSS variables are set via Sass, so Sass customization is still supported, too.

  --#{$prefix}accordion-color: #{$accordion-color};
  --#{$prefix}accordion-bg: #{$accordion-bg};
  --#{$prefix}accordion-transition: #{$accordion-transition};
  --#{$prefix}accordion-border-color: #{$accordion-border-color};
  --#{$prefix}accordion-border-width: #{$accordion-border-width};
  --#{$prefix}accordion-border-radius: #{$accordion-border-radius};
  --#{$prefix}accordion-inner-border-radius: #{$accordion-inner-border-radius};
  --#{$prefix}accordion-btn-padding-x: #{$accordion-button-padding-x};
  --#{$prefix}accordion-btn-padding-y: #{$accordion-button-padding-y};
  --#{$prefix}accordion-btn-font-size: #{$accordion-button-font-size}; // Boosted mod
  --#{$prefix}accordion-btn-font-weight: #{$accordion-button-font-weight}; // Boosted mod
  --#{$prefix}accordion-btn-line-height: #{$accordion-button-line-height}; // Boosted mod
  --#{$prefix}accordion-btn-letter-spacing: #{$accordion-button-letter-spacing}; // Boosted mod
  --#{$prefix}accordion-btn-color: #{$accordion-button-color};
  --#{$prefix}accordion-btn-bg: #{$accordion-button-bg};
  // Boosted mod: no --#{$prefix}accordion-btn-icon
  // Boosted mod: no --#{$prefix}accordion-btn-icon-width
  --#{$prefix}accordion-btn-icon-transform: #{$accordion-icon-transform};
  // Boosted mod: no --#{$prefix}accordion-btn-icon-transition
  // Boosted mod: no --#{$prefix}accordion-btn-active-icon
  // Boosted mod: no --#{$prefix}accordion-btn-focus-border-color
  // Boosted mod: no --#{$prefix}accordion-btn-focus-box-shadow
  --#{$prefix}accordion-body-padding-x: #{$accordion-body-padding-x};
  --#{$prefix}accordion-body-padding-y: #{$accordion-body-padding-y};
  --#{$prefix}accordion-active-color: #{$accordion-button-active-color};
  --#{$prefix}accordion-active-bg: #{$accordion-button-active-bg};

Small and large accordion modifier classes are used to update the value of these CSS variables as needed:

  --#{$prefix}accordion-btn-font-size: #{$accordion-button-font-size-sm};
  --#{$prefix}accordion-btn-line-height: #{$accordion-button-line-height-sm};
  --#{$prefix}accordion-btn-letter-spacing: #{$accordion-button-letter-spacing-sm};

  --#{$prefix}accordion-btn-font-size: #{$accordion-button-font-size-lg};
  --#{$prefix}accordion-btn-line-height: #{$accordion-button-line-height-lg};
  --#{$prefix}accordion-btn-letter-spacing: #{$accordion-button-letter-spacing-lg};

Customization through CSS variables can be seen on the .accordion-dark modifier class where we override specific values without adding duplicate CSS selectors.

  --#{$prefix}accordion-btn-color: #{$accordion-dark-button-color};
  --#{$prefix}accordion-btn-bg: #{$accordion-dark-button-bg};
  --#{$prefix}accordion-active-color: #{$accordion-dark-button-active-color};
  --#{$prefix}accordion-border-color: #{$accordion-dark-border-color};
  --#{$prefix}accordion-color: #{$accordion-dark-color};
  --#{$prefix}accordion-bg: #{$accordion-dark-bg};

Sass variables

Variables for all accordions:

$accordion-padding-y:                     $spacer * .5; // Boosted mod
$accordion-padding-x:                     0; // Boosted mod
$accordion-color:                         var(--#{$prefix}body-color);
$accordion-bg:                            $body-bg;
$accordion-border-width:                  $border-width * .5; // Boosted mod
$accordion-border-color:                  $gray-500; // Boosted mod
$accordion-border-radius:                 $border-radius;
$accordion-inner-border-radius:           subtract($accordion-border-radius, #{$accordion-border-width});

$accordion-body-padding-y:                $spacer; // Boosted mod
$accordion-body-padding-x:                $spacer; // Boosted mod

$accordion-button-padding-y:              $accordion-padding-y;
$accordion-button-padding-x:              $accordion-padding-x;
$accordion-button-color:                  $accordion-color;
$accordion-button-bg:                     var(--#{$prefix}accordion-bg);
$accordion-transition:                    $btn-transition, border-radius .15s ease;
$accordion-button-active-bg:              null; // Boosted mod
$accordion-button-active-color:           $accessible-orange; // Boosted mod

// Boosted mod: no $accordion-button-focus-border-color
// Boosted mod: no $accordion-button-focus-box-shadow

// Boosted mod: no $accordion-icon-width
// Boosted mod: no $accordion-icon-transition
$accordion-icon-transform:                scaleY(-1);

// Boosted mod: no $accordion-button-icon
// Boosted mod: no $accordion-button-active-icon

// Boosted mod: accordion sizes
$accordion-button-font-size:              $h3-font-size;
$accordion-button-line-height:            null;
$accordion-button-font-weight:            $font-weight-bold;
$accordion-button-letter-spacing:         $h3-spacing;
$accordion-button-font-size-sm:           $h5-font-size;
$accordion-button-line-height-sm:         $h5-line-height;
$accordion-button-letter-spacing-sm:      $h5-spacing;
$accordion-button-font-size-lg:           $h2-font-size;
$accordion-button-line-height-lg:         calc(40 / 30); // stylelint-disable-line function-disallowed-list
$accordion-button-letter-spacing-lg:      $h2-spacing;
// End mod

Variables for the dark accordion:

$accordion-dark-color:                    $white; // Boosted mod
$accordion-dark-bg:                       $black; // Boosted mod
$accordion-dark-border-color:             $gray-700; // Boosted mod
$accordion-dark-button-color:             $accordion-dark-color; // Boosted mod
$accordion-dark-button-bg:                $accordion-dark-bg; // Boosted mod
$accordion-dark-button-active-color:      $brand-orange; // Boosted mod