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.
<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="collapse" id="collapse-908">
<div class="card card-body mt-2">
Friendly people answer your questions quickly, by phone, chat or email. Track your progress in the app and see how far you have come.
</div>
</div>2Link toggle
A link with href="#id" and role="button" works the same way.
Nutrition plans fit your routine and the food you actually enjoy.
<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="collapse" id="collapse-909">
<p class="small text-body-secondary mt-2 mb-0">Nutrition plans fit your routine and the food you actually enjoy.</p>
</div>3Horizontal collapse
collapse-horizontal animates the width; the content needs a fixed width.
<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="collapse collapse-horizontal" id="collapse-910">
<div class="card card-body" style="width: 260px;">
Pause or change your membership any time, with no long contracts.
</div>
</div>
</div>4Multiple targets
One button can toggle several elements by targeting a shared class.
<div class="d-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="collapse multi-group-913" id="multi-911">
<div class="card card-body">
Thousands of members already trust us, and we work hard to keep it that way.
</div>
</div>
</div>
<div class="col-sm-6">
<div class="collapse multi-group-913" id="multi-912">
<div class="card card-body">
Our team has done this many times, so you never have to guess.
</div>
</div>
</div>
</div>5Read more
Show the first part of a text and reveal the rest on demand.
Our recovery spa has a sauna, cold plunge and massage rooms. Open 24 hours, so you can train whenever it suits your day.
We listen first, then build a plan around what you actually need. Pause or change your membership any time, with no long contracts. We measure success by how many members come back and tell their friends.
<p class="mb-1">Our recovery spa has a sauna, cold plunge and massage rooms. Open 24 hours, so you can train whenever it suits your day.</p>
<div class="collapse" id="more-914">
<p class="mb-1">We listen first, then build a plan around what you actually need. Pause or change your membership any time, with no long contracts. We measure success by how many members come back and tell their friends.</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="d-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="collapse" id="filters-915">
<div class="border rounded p-3 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="Jonah Kim">
</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 p-2" style="max-width: 260px;" aria-label="Admin menu">
<ul class="nav flex-column">
<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 d-flex justify-content-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="collapse show" id="menu-918"><ul class="nav flex-column ms-4 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 d-flex justify-content-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="collapse" id="menu-919"><ul class="nav flex-column ms-4 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-5351 | $669.46 | |
Billed to Noah Moreau, Singapore. Due Nov 2, 2026. | ||
| #INV-6169 | $434.56 | |
Billed to Mia Duarte, Denver. Due Nov 16, 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="visually-hidden">Details</span></th>
</tr>
</thead>
<tbody>
<tr>
<td>#TX-5351</td>
<td>$669.46</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="visually-hidden">Show details</span></button></td>
</tr>
<tr>
<td colspan="3" class="p-0 border-0"><div class="collapse" id="row-detail-920"><div class="p-3 bg-body-tertiary small">Billed to Noah Moreau, Singapore. Due Nov 2, 2026.</div></div></td>
</tr>
<tr>
<td>#INV-6169</td>
<td>$434.56</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="visually-hidden">Show details</span></button></td>
</tr>
<tr>
<td colspan="3" class="p-0 border-0"><div class="collapse" id="row-detail-921"><div class="p-3 bg-body-tertiary small">Billed to Mia Duarte, Denver. Due Nov 16, 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="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="the-small-habits-that-make-a-big-difference">
<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.
<div class="card" style="max-width: 26rem;">
<div class="card-header d-flex justify-content-between align-items-center">
<span class="fw-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="visually-hidden">Minimise</span></button>
</div>
<div class="collapse show" id="widget-925">
<div class="card-body">
<div class="fs-3 fw-bold">
46.5k
</div>
<div class="small text-success">
<i class="bi bi-arrow-up" aria-hidden="true"></i> 24% this week
</div>
</div>
</div>
</div>11Open by default
Add .show to start expanded; the button's aria-expanded is then true.
<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="collapse show" id="collapse-926">
<div class="alert alert-secondary mt-2 mb-0">
Clear prices, honest advice and no surprises along the way. Small group classes mean your coach knows your name and your form.
</div>
</div>12Rotating chevron
A chevron that turns when the panel opens, driven by aria-expanded in CSS.
<button class="btn btn-light border w-100 d-flex justify-content-between align-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="collapse" id="collapse-927" style="max-width: 420px;">
<div class="p-3 small">
Nutrition plans fit your routine and the food you actually enjoy.
</div>
</div>13Comments thread
Keep a feed short and let readers open the replies.
Our team has done this many times, so you never have to guess.
View 2 replies<p class="mb-1">Our team has done this many times, so you never have to guess.</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="collapse" id="comments-928">
<div class="mt-2 ps-3 border-start">
<div class="d-flex gap-2 mb-2">
<img src="../assets/img/avatar-10.svg" alt="Theo Silva" class="rounded-circle flex-shrink-0" width="32" height="32">
<div class="bg-body-tertiary rounded p-2 small">
<strong>Theo Silva</strong> Track your progress in the app and see how far you have come.
</div>
</div>
<div class="d-flex gap-2 mb-2">
<img src="../assets/img/avatar-5.svg" alt="Freya Morgan" class="rounded-circle flex-shrink-0" width="32" height="32">
<div class="bg-body-tertiary rounded p-2 small">
<strong>Freya Morgan</strong> More than sixty classes a week, from sunrise yoga to late-night spin.
</div>
</div>
</div>
</div>14Release notes
A compact version line that expands into the full change list.
- Community events
- Modern equipment
- Faster loading on slow connections
<div class="border rounded p-3">
<div class="d-flex justify-content-between align-items-center">
<div>
<span class="fw-semibold">Version 3.1</span> <span class="badge text-bg-success">Stable</span>
<div class="small text-body-secondary">
Jul 16, 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="collapse" id="notes-929">
<ul class="small mt-3 mb-0">
<li>Community events</li>
<li>Modern equipment</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
- 3.3 kg
- Dimensions
- 40 x 32 x 6 cm
- Warranty
- 1 years
<button class="btn btn-outline-secondary w-100" 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="collapse" id="specs-930">
<dl class="row small border rounded p-3 mt-2 mb-0">
<dt class="col-sm-4">Weight</dt>
<dd class="col-sm-8">3.3 kg</dd>
<dt class="col-sm-4">Dimensions</dt>
<dd class="col-sm-8">40 x 32 x 6 cm</dd>
<dt class="col-sm-4">Warranty</dt>
<dd class="col-sm-8 mb-0">1 years</dd>
</dl>
</div>16Expandable search bar
A search icon in a header opens a full-width search field below it.
<div class="border rounded">
<div class="d-flex align-items-center justify-content-between p-2">
<span class="fw-bold">Sageo Studio</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="visually-hidden">Search</span></button>
</div>
<div class="collapse" id="msearch-931">
<div class="p-2 border-top">
<label class="visually-hidden" for="msearch-input-932">Search</label>
<input type="search" class="form-control" id="msearch-input-932" placeholder="Search Sageo Studio">
</div>
</div>
</div>17Onboarding checklist
Each checklist step expands to explain what to do.
Start in minutes and get help from a real person whenever you need it.
Online coaching keeps you on track when you travel.
Open 24 hours, so you can train whenever it suits your day.
<div class="list-group" style="max-width: 480px;">
<div class="list-group-item">
<button class="btn btn-link p-0 text-decoration-none link-body-emphasis d-flex align-items-center gap-2 w-100 text-start" type="button" data-ui-toggle="collapse" data-ui-target="#step-933" aria-expanded="false" aria-controls="step-933"><span class="text-success"><i class="bi bi-check-circle-fill" aria-hidden="true"></i></span>Verify your email</button>
<div class="collapse" id="step-933">
<p class="small text-body-secondary mt-2 mb-1 ms-4">Start in minutes and get help from a real person whenever you need it.</p>
</div>
</div>
<div class="list-group-item">
<button class="btn btn-link p-0 text-decoration-none link-body-emphasis d-flex align-items-center gap-2 w-100 text-start" type="button" data-ui-toggle="collapse" data-ui-target="#step-934" aria-expanded="false" aria-controls="step-934"><span class="text-body-tertiary"><i class="bi bi-circle" aria-hidden="true"></i></span>Add a payment method</button>
<div class="collapse" id="step-934">
<p class="small text-body-secondary mt-2 mb-1 ms-4">Online coaching keeps you on track when you travel.</p>
</div>
</div>
<div class="list-group-item">
<button class="btn btn-link p-0 text-decoration-none link-body-emphasis d-flex align-items-center gap-2 w-100 text-start" type="button" data-ui-toggle="collapse" data-ui-target="#step-935" aria-expanded="false" aria-controls="step-935"><span class="text-body-tertiary"><i class="bi bi-circle" aria-hidden="true"></i></span>Invite a teammate</button>
<div class="collapse" id="step-935">
<p class="small text-body-secondary mt-2 mb-1 ms-4">Open 24 hours, so you can train whenever it suits your day.</p>
</div>
</div>
</div>18Swap two panels
Two collapses sharing a class swap places: one hides while the other shows.
Read-only view: Community events keep you motivated, from fun runs to workshops.
<div class="pane-group-938">
<div class="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: Community events keep you motivated, from fun runs to workshops.</p>
<button class="btn btn-primary btn-sm align-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="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">Beginners are always welcome, with an intro session included.</textarea>
<button class="btn btn-success btn-sm align-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.
- Modern equipment is cleaned, serviced and ready every day.
- Thousands of members already trust us, and we work hard to keep it that way.
- Certified coaches design every session around your level and your goals.
<ul class="list-group" style="max-width: 420px;">
<li class="list-group-item small"><i class="bi bi-bell" aria-hidden="true"></i> Modern equipment is cleaned, serviced and ready every day.</li>
<li class="list-group-item p-0"><div class="collapse" id="group-939"><ul class="list-group list-group-flush"><li class="list-group-item small text-body-secondary">Thousands of members already trust us, and we work hard to keep it that way.</li><li class="list-group-item small text-body-secondary">Certified coaches design every session around your level and your goals.</li></ul></div><button class="btn btn-link btn-sm w-100" type="button" data-ui-toggle="collapse" data-ui-target="#group-939" aria-expanded="false" aria-controls="group-939">Show 9 earlier</button></li>
</ul>20Nested collapse
A collapse inside another for drilling into details step by step.
We listen first, then build a plan around what you actually need.
- Design: $3,222.21
- Development: $12,024.31
- Marketing: $5,609.67
<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="collapse" id="outer-940">
<div class="card card-body mt-2">
<p>We listen first, then build a plan around what you actually need.</p>
<button class="btn btn-sm btn-outline-secondary align-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="collapse" id="inner-941">
<ul class="small mt-2 mb-0">
<li>Design: $3,222.21</li>
<li>Development: $12,024.31</li>
<li>Marketing: $5,609.67</li>
</ul>
</div>
</div>
</div>