Collapse shows and hides content with a short animation. Point a button or link at the target with data-ui-toggle="collapse", keep aria-expanded and aria-controls in sync, and use it for read-more text, filter panels, sub-menus and expandable rows.
1Button toggle
A button with data-ui-toggle="collapse" shows and hides the target.
Our specialists take time to listen and explain every step of your treatment. Friendly reminders make sure you never miss a check-up or a dose.
<button class="btn btn-primary" type="button" data-ui-toggle="collapse" data-ui-target="#collapse-908" aria-expanded="false" aria-controls="collapse-908">Toggle details</button>
<div class="ui-collapse" id="collapse-908">
<div class="card card-body mt-2">
Our specialists take time to listen and explain every step of your treatment. Friendly reminders make sure you never miss a check-up or a dose.
</div>
</div>2Link toggle
A link with href="#id" and role="button" works the same way.
What does this mean?
Friendly people answer your questions quickly, by phone, chat or email.
<a class="link-primary" data-ui-toggle="collapse" href="#collapse-909" role="button" aria-expanded="false" aria-controls="collapse-909"><i class="bi bi-info-circle" aria-hidden="true"></i> What does this mean?</a>
<div class="ui-collapse" id="collapse-909">
<p class="small text-muted mt-2 mb-0">Friendly people answer your questions quickly, by phone, chat or email.</p>
</div>3Horizontal collapse
collapse-horizontal animates the width; the content needs a fixed width.
Our team has done this many times, so you never have to guess.
<button class="btn btn-outline-primary" type="button" data-ui-toggle="collapse" data-ui-target="#collapse-910" aria-expanded="false" aria-controls="collapse-910">Toggle width</button>
<div style="min-height: 110px;" class="mt-2">
<div class="ui-collapse collapse-horizontal" id="collapse-910">
<div class="card card-body" style="width: 260px;">
Our team has done this many times, so you never have to guess.
</div>
</div>
</div>4Multiple targets
One button can toggle several elements by targeting a shared class.
Book online in two minutes and see a doctor as soon as today.
Family plans cover check-ups and vaccinations for everyone under one roof.
<div class="flex flex-wrap gap-2 mb-2">
<button class="btn btn-outline-secondary" type="button" data-ui-toggle="collapse" data-ui-target="#multi-911" aria-expanded="false" aria-controls="multi-911">Toggle first</button>
<button class="btn btn-outline-secondary" type="button" data-ui-toggle="collapse" data-ui-target="#multi-912" aria-expanded="false" aria-controls="multi-912">Toggle second</button>
<button class="btn btn-primary" type="button" data-ui-toggle="collapse" data-ui-target=".multi-group-913" aria-expanded="false" aria-controls="multi-911 multi-912">Toggle both</button>
</div>
<div class="row g-2">
<div class="col-sm-6">
<div class="ui-collapse multi-group-913" id="multi-911">
<div class="card card-body">
Book online in two minutes and see a doctor as soon as today.
</div>
</div>
</div>
<div class="col-sm-6">
<div class="ui-collapse multi-group-913" id="multi-912">
<div class="card card-body">
Family plans cover check-ups and vaccinations for everyone under one roof.
</div>
</div>
</div>
</div>5Read more
Show the first part of a text and reveal the rest on demand.
Thousands of patients already trust us, and we work hard to keep it that way. We listen first, then build a plan around what you actually need.
Same-day appointments are available for urgent needs on weekdays. Children are welcome, and our paediatric team knows how to make them smile. Same-day appointments are available for urgent needs on weekdays.
<p class="mb-1">Thousands of patients already trust us, and we work hard to keep it that way. We listen first, then build a plan around what you actually need.</p>
<div class="ui-collapse" id="more-914">
<p class="mb-1">Same-day appointments are available for urgent needs on weekdays. Children are welcome, and our paediatric team knows how to make them smile. Same-day appointments are available for urgent needs on weekdays.</p>
</div>
<button class="btn btn-link px-0 ca-more" type="button" data-ui-toggle="collapse" data-ui-target="#more-914" aria-expanded="false" aria-controls="more-914"><span class="ca-more-show">Read more</span><span class="ca-more-hide">Show less</span></button>6Filter panel
A filter button above a table reveals extra search fields.
<div class="flex gap-2">
<input type="search" class="form-control" placeholder="Search orders" aria-label="Search orders" style="max-width: 280px;">
<button class="btn btn-outline-secondary" type="button" data-ui-toggle="collapse" data-ui-target="#filters-915" aria-expanded="false" aria-controls="filters-915"><i class="bi bi-sliders" aria-hidden="true"></i> Filters</button>
</div>
<div class="ui-collapse" id="filters-915">
<div class="border rounded-md p-4 mt-2 row g-2">
<div class="col-sm-6">
<label class="form-label small" for="filter-q-916">Customer</label>
<input class="form-control form-control-sm" id="filter-q-916" type="text" placeholder="Noah Novak">
</div>
<div class="col-sm-6">
<label class="form-label small" for="filter-status-917">Status</label>
<select class="form-select form-select-sm" id="filter-status-917">
<option>Any</option>
<option>Paid</option>
<option>Pending</option>
<option>Refunded</option>
</select>
</div>
<div class="col-12 text-end">
<button type="button" class="btn btn-primary btn-sm">Apply</button>
</div>
</div>
</div>7Sidebar sub-menus
Nested navigation where each section expands to show its links.
<nav class="border rounded-md p-2" style="max-width: 260px;" aria-label="Admin menu">
<ul class="nav flex-col">
<li class="nav-item"><a class="nav-link link-body-emphasis" href="#"><i class="bi bi-house" aria-hidden="true"></i> Home</a></li>
<li class="nav-item"><a class="nav-link link-body-emphasis flex justify-between" data-ui-toggle="collapse" href="#menu-918" role="button" aria-expanded="true" aria-controls="menu-918"><span><i class="bi bi-bag" aria-hidden="true"></i> Sales</span><i class="bi bi-chevron-down" aria-hidden="true"></i></a><div class="ui-collapse show" id="menu-918"><ul class="nav flex-col ms-6 small"><li class="nav-item"><a class="nav-link py-1" href="#">Orders</a></li><li class="nav-item"><a class="nav-link py-1" href="#">Invoices</a></li></ul></div></li>
<li class="nav-item"><a class="nav-link link-body-emphasis flex justify-between" data-ui-toggle="collapse" href="#menu-919" role="button" aria-expanded="false" aria-controls="menu-919"><span><i class="bi bi-bar-chart" aria-hidden="true"></i> Reports</span><i class="bi bi-chevron-down" aria-hidden="true"></i></a><div class="ui-collapse" id="menu-919"><ul class="nav flex-col ms-6 small"><li class="nav-item"><a class="nav-link py-1" href="#">Weekly</a></li><li class="nav-item"><a class="nav-link py-1" href="#">Monthly</a></li></ul></div></li>
</ul>
</nav>8Expandable table rows
A detail row under each table row opens with a small toggle.
| Invoice | Amount | Details |
|---|---|---|
| #TX-3414 | $151.33 | |
Billed to Arjun Patel, Austin. Due Feb 8, 2027. | ||
| #TX-2856 | $552.62 | |
Billed to Omar Moreau, Barcelona. Due Nov 20, 2026. | ||
<div class="table-responsive">
<table class="table align-middle mb-0">
<thead>
<tr>
<th scope="col">Invoice</th>
<th scope="col">Amount</th>
<th scope="col"><span class="sr-only">Details</span></th>
</tr>
</thead>
<tbody>
<tr>
<td>#TX-3414</td>
<td>$151.33</td>
<td class="text-end"><button class="btn btn-sm btn-light border" type="button" data-ui-toggle="collapse" data-ui-target="#row-detail-920" aria-expanded="false" aria-controls="row-detail-920"><i class="bi bi-chevron-expand" aria-hidden="true"></i><span class="sr-only">Show details</span></button></td>
</tr>
<tr>
<td colspan="3" class="p-0 border-0"><div class="ui-collapse" id="row-detail-920"><div class="p-4 bg-surface-3 small">Billed to Arjun Patel, Austin. Due Feb 8, 2027.</div></div></td>
</tr>
<tr>
<td>#TX-2856</td>
<td>$552.62</td>
<td class="text-end"><button class="btn btn-sm btn-light border" type="button" data-ui-toggle="collapse" data-ui-target="#row-detail-921" aria-expanded="false" aria-controls="row-detail-921"><i class="bi bi-chevron-expand" aria-hidden="true"></i><span class="sr-only">Show details</span></button></td>
</tr>
<tr>
<td colspan="3" class="p-0 border-0"><div class="ui-collapse" id="row-detail-921"><div class="p-4 bg-surface-3 small">Billed to Omar Moreau, Barcelona. Due Nov 20, 2026.</div></div></td>
</tr>
</tbody>
</table>
</div>9Advanced form options
Hide rarely used settings behind an "Advanced" toggle.
<div style="max-width: 420px;">
<a class="small" data-ui-toggle="collapse" href="#advanced-922" role="button" aria-expanded="false" aria-controls="advanced-922"><i class="bi bi-gear" aria-hidden="true"></i> Advanced options</a>
<div class="ui-collapse" id="advanced-922">
<div class="mt-2">
<label class="form-label small" for="adv-slug-923">URL slug</label>
<input class="form-control form-control-sm mb-2" id="adv-slug-923" type="text" value="a-simple-monthly-skin-check">
<div class="form-check">
<input class="form-check-input" type="checkbox" id="adv-index-924">
<label class="form-check-label small" for="adv-index-924">Hide from search engines</label>
</div>
</div>
</div>
</div>10Minimisable card
A header button collapses the card body, as in dashboard widgets.
Traffic
57.1k
26% this week
<div class="card" style="max-width: 26rem;">
<div class="card-header flex justify-between items-center">
<span class="font-semibold"><i class="bi bi-graph-up" aria-hidden="true"></i> Traffic</span>
<button class="btn btn-sm btn-link link-secondary p-0" type="button" data-ui-toggle="collapse" data-ui-target="#widget-925" aria-expanded="true" aria-controls="widget-925"><i class="bi bi-dash-square" aria-hidden="true"></i><span class="sr-only">Minimise</span></button>
</div>
<div class="ui-collapse show" id="widget-925">
<div class="card-body">
<div class="text-2xl font-bold">
57.1k
</div>
<div class="small text-success-emphasis">
<i class="bi bi-arrow-up" aria-hidden="true"></i> 26% this week
</div>
</div>
</div>
</div>11Open by default
Add .show to start expanded; the button's aria-expanded is then true.
Friendly reminders make sure you never miss a check-up or a dose. Our team has done this many times, so you never have to guess.
<button class="btn btn-outline-dark btn-sm" type="button" data-ui-toggle="collapse" data-ui-target="#collapse-926" aria-expanded="true" aria-controls="collapse-926">Hide summary</button>
<div class="ui-collapse show" id="collapse-926">
<div class="alert alert-secondary mt-2 mb-0">
Friendly reminders make sure you never miss a check-up or a dose. Our team has done this many times, so you never have to guess.
</div>
</div>12Rotating chevron
A chevron that turns when the panel opens, driven by aria-expanded in CSS.
We listen first, then build a plan around what you actually need.
<button class="btn btn-light border w-full flex justify-between items-center ca-chev" type="button" data-ui-toggle="collapse" data-ui-target="#collapse-927" aria-expanded="false" aria-controls="collapse-927" style="max-width: 420px;">Shipping & returns<i class="bi bi-chevron-down" aria-hidden="true"></i></button>
<div class="ui-collapse" id="collapse-927" style="max-width: 420px;">
<div class="p-4 small">
We listen first, then build a plan around what you actually need.
</div>
</div>13Comments thread
Keep a feed short and let readers open the replies.
Modern equipment means faster diagnoses and more comfortable treatment.
View 2 replies
Theo Whitaker Video consultations let you speak with a doctor from the comfort of home.
Kenji Larsen Friendly people answer your questions quickly, by phone, chat or email.
<p class="mb-1">Modern equipment means faster diagnoses and more comfortable treatment.</p>
<a class="small" data-ui-toggle="collapse" href="#comments-928" role="button" aria-expanded="false" aria-controls="comments-928"><i class="bi bi-chat" aria-hidden="true"></i> View 2 replies</a>
<div class="ui-collapse" id="comments-928">
<div class="mt-2 ps-4 border-s">
<div class="flex gap-2 mb-2">
<img src="../assets/img/avatar-3.svg" alt="Theo Whitaker" class="rounded-full shrink-0" width="32" height="32">
<div class="bg-surface-3 rounded-md p-2 small">
<strong>Theo Whitaker</strong> Video consultations let you speak with a doctor from the comfort of home.
</div>
</div>
<div class="flex gap-2 mb-2">
<img src="../assets/img/avatar-8.svg" alt="Kenji Larsen" class="rounded-full shrink-0" width="32" height="32">
<div class="bg-surface-3 rounded-md p-2 small">
<strong>Kenji Larsen</strong> Friendly people answer your questions quickly, by phone, chat or email.
</div>
</div>
</div>
</div>14Release notes
A compact version line that expands into the full change list.
Version 3.6 Stable
Jun 9, 2026
- Insurance friendly
- Certified specialists
- Faster loading on slow connections
<div class="border rounded-md p-4">
<div class="flex justify-between items-center">
<div>
<span class="font-semibold">Version 3.6</span> <span class="badge text-bg-success">Stable</span>
<div class="small text-muted">
Jun 9, 2026
</div>
</div>
<button class="btn btn-outline-primary btn-sm" type="button" data-ui-toggle="collapse" data-ui-target="#notes-929" aria-expanded="false" aria-controls="notes-929">What's new</button>
</div>
<div class="ui-collapse" id="notes-929">
<ul class="small mt-4 mb-0">
<li>Insurance friendly</li>
<li>Certified specialists</li>
<li>Faster loading on slow connections</li>
</ul>
</div>
</div>15Specification list
A definition list of technical details hidden behind a full-width toggle.
- Weight
- 2.1 kg
- Dimensions
- 39 x 21 x 12 cm
- Warranty
- 2 years
<button class="btn btn-outline-secondary w-full" type="button" data-ui-toggle="collapse" data-ui-target="#specs-930" aria-expanded="false" aria-controls="specs-930"><i class="bi bi-list-columns-reverse" aria-hidden="true"></i> Full specifications</button>
<div class="ui-collapse" id="specs-930">
<dl class="row small border rounded-md p-4 mt-2 mb-0">
<dt class="col-sm-4">Weight</dt>
<dd class="col-sm-8">2.1 kg</dd>
<dt class="col-sm-4">Dimensions</dt>
<dd class="col-sm-8">39 x 21 x 12 cm</dd>
<dt class="col-sm-4">Warranty</dt>
<dd class="col-sm-8 mb-0">2 years</dd>
</dl>
</div>16Expandable search bar
A search icon in a header opens a full-width search field below it.
Umbra
<div class="border rounded-md">
<div class="flex items-center justify-between p-2">
<span class="font-bold">Umbra</span>
<button class="btn btn-light" type="button" data-ui-toggle="collapse" data-ui-target="#msearch-931" aria-expanded="false" aria-controls="msearch-931"><i class="bi bi-search" aria-hidden="true"></i><span class="sr-only">Search</span></button>
</div>
<div class="ui-collapse" id="msearch-931">
<div class="p-2 border-t">
<label class="sr-only" for="msearch-input-932">Search</label>
<input type="search" class="form-control" id="msearch-input-932" placeholder="Search Umbra">
</div>
</div>
</div>17Onboarding checklist
Each checklist step expands to explain what to do.
Every detail is handled by people who care about getting it right.
Family plans cover check-ups and vaccinations for everyone under one roof.
Thousands of patients already trust us, and we work hard to keep it that way.
<div class="list-group" style="max-width: 480px;">
<div class="list-group-item">
<button class="btn btn-link p-0 no-underline link-body-emphasis flex items-center gap-2 w-full text-start" type="button" data-ui-toggle="collapse" data-ui-target="#step-933" aria-expanded="false" aria-controls="step-933"><span class="text-success-emphasis"><i class="bi bi-check-circle-fill" aria-hidden="true"></i></span>Verify your email</button>
<div class="ui-collapse" id="step-933">
<p class="small text-muted mt-2 mb-1 ms-6">Every detail is handled by people who care about getting it right.</p>
</div>
</div>
<div class="list-group-item">
<button class="btn btn-link p-0 no-underline link-body-emphasis flex items-center gap-2 w-full text-start" type="button" data-ui-toggle="collapse" data-ui-target="#step-934" aria-expanded="false" aria-controls="step-934"><span class="text-tertiary"><i class="bi bi-circle" aria-hidden="true"></i></span>Add a payment method</button>
<div class="ui-collapse" id="step-934">
<p class="small text-muted mt-2 mb-1 ms-6">Family plans cover check-ups and vaccinations for everyone under one roof.</p>
</div>
</div>
<div class="list-group-item">
<button class="btn btn-link p-0 no-underline link-body-emphasis flex items-center gap-2 w-full text-start" type="button" data-ui-toggle="collapse" data-ui-target="#step-935" aria-expanded="false" aria-controls="step-935"><span class="text-tertiary"><i class="bi bi-circle" aria-hidden="true"></i></span>Invite a teammate</button>
<div class="ui-collapse" id="step-935">
<p class="small text-muted mt-2 mb-1 ms-6">Thousands of patients already trust us, and we work hard to keep it that way.</p>
</div>
</div>
</div>18Swap two panels
Two collapses sharing a class swap places: one hides while the other shows.
Read-only view: We keep things simple, so you can focus on what matters to you.
<div class="pane-group-938">
<div class="ui-collapse show pane-group-938-p" id="pane-936">
<div class="card card-body">
<p><i class="bi bi-eye" aria-hidden="true"></i> Read-only view: We keep things simple, so you can focus on what matters to you.</p>
<button class="btn btn-primary btn-sm self-start" type="button" data-ui-toggle="collapse" data-ui-target=".pane-group-938-p" aria-expanded="true" aria-controls="pane-936 pane-937"><i class="bi bi-pencil" aria-hidden="true"></i> Edit</button>
</div>
</div>
<div class="ui-collapse pane-group-938-p" id="pane-937">
<div class="card card-body">
<label class="form-label" for="pane-937-text">Description</label>
<textarea class="form-control mb-2" id="pane-937-text" rows="2">We work with most insurance providers and explain any costs upfront.</textarea>
<button class="btn btn-success btn-sm self-start" type="button" data-ui-toggle="collapse" data-ui-target=".pane-group-938-p" aria-expanded="false" aria-controls="pane-936 pane-937"><i class="bi bi-check-lg" aria-hidden="true"></i> Done</button>
</div>
</div>
</div>19Grouped notifications
Older notifications collapse into a single "show earlier" row.
- Our clinic is fully accessible, with free parking right outside.
- Our specialists take time to listen and explain every step of your treatment.
- We measure success by how many patients come back and tell their friends.
<ul class="list-group" style="max-width: 420px;">
<li class="list-group-item small"><i class="bi bi-bell" aria-hidden="true"></i> Our clinic is fully accessible, with free parking right outside.</li>
<li class="list-group-item p-0"><div class="ui-collapse" id="group-939"><ul class="list-group list-group-flush"><li class="list-group-item small text-muted">Our specialists take time to listen and explain every step of your treatment.</li><li class="list-group-item small text-muted">We measure success by how many patients come back and tell their friends.</li></ul></div><button class="btn btn-link btn-sm w-full" type="button" data-ui-toggle="collapse" data-ui-target="#group-939" aria-expanded="false" aria-controls="group-939">Show 7 earlier</button></li>
</ul>20Nested collapse
A collapse inside another for drilling into details step by step.
Book online in two minutes and see a doctor as soon as today.
- Design: $4,281.94
- Development: $18,039.46
- Marketing: $7,851.00
<button class="btn btn-outline-primary" type="button" data-ui-toggle="collapse" data-ui-target="#outer-940" aria-expanded="false" aria-controls="outer-940">Project details</button>
<div class="ui-collapse" id="outer-940">
<div class="card card-body mt-2">
<p>Book online in two minutes and see a doctor as soon as today.</p>
<button class="btn btn-sm btn-outline-secondary self-start" type="button" data-ui-toggle="collapse" data-ui-target="#inner-941" aria-expanded="false" aria-controls="inner-941">Budget breakdown</button>
<div class="ui-collapse" id="inner-941">
<ul class="small mt-2 mb-0">
<li>Design: $4,281.94</li>
<li>Development: $18,039.46</li>
<li>Marketing: $7,851.00</li>
</ul>
</div>
</div>
</div>