Collapse
Collapse shows and hides content with a short animation. Point a button or link at the target with data-bs-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-bs-toggle="collapse" shows and hides the target.
<button class="btn btn-primary" type="button" data-bs-toggle="collapse" data-bs-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. Guided learning paths take you from beginner to job-ready step by step.
</div>
</div>2Link toggle
A link with href="#id" and role="button" works the same way.
We keep things simple, so you can focus on what matters to you.
<a class="link-primary" data-bs-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">We keep things simple, so you can focus on what matters to you.</p>
</div>3Horizontal collapse
collapse-horizontal animates the width; the content needs a fixed width.
<button class="btn btn-outline-primary" type="button" data-bs-toggle="collapse" data-bs-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;">
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.
<div class="d-flex flex-wrap gap-2 mb-2">
<button class="btn btn-outline-secondary" type="button" data-bs-toggle="collapse" data-bs-target="#multi-911" aria-expanded="false" aria-controls="multi-911">Toggle first</button>
<button class="btn btn-outline-secondary" type="button" data-bs-toggle="collapse" data-bs-target="#multi-912" aria-expanded="false" aria-controls="multi-912">Toggle second</button>
<button class="btn btn-primary" type="button" data-bs-toggle="collapse" data-bs-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">
We measure success by how many students come back and tell their friends.
</div>
</div>
</div>
<div class="col-sm-6">
<div class="collapse multi-group-913" id="multi-912">
<div class="card card-body">
Try the first lesson of any course for free before you decide.
</div>
</div>
</div>
</div>5Read more
Show the first part of a text and reveal the rest on demand.
Clear prices, honest advice and no surprises along the way. Short quizzes after each lesson help new knowledge stick.
Thousands of students already trust us, and we work hard to keep it that way. Lifetime access means you can revisit lessons whenever you need a refresher. Earn a certificate at the end of each course and share it with employers.
<p class="mb-1">Clear prices, honest advice and no surprises along the way. Short quizzes after each lesson help new knowledge stick.</p>
<div class="collapse" id="more-914">
<p class="mb-1">Thousands of students already trust us, and we work hard to keep it that way. Lifetime access means you can revisit lessons whenever you need a refresher. Earn a certificate at the end of each course and share it with employers.</p>
</div>
<button class="btn btn-link px-0 ca-more" type="button" data-bs-toggle="collapse" data-bs-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-bs-toggle="collapse" data-bs-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="Chloe Rossi">
</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-bs-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-bs-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-8790 | $254.62 | |
Billed to Diego Morgan, Dublin. Due Dec 28, 2026. | ||
| #ORD-5732 | $784.26 | |
Billed to Mateo Moreau, Valencia. Due Feb 8, 2027. | ||
<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-8790</td>
<td>$254.62</td>
<td class="text-end"><button class="btn btn-sm btn-light border" type="button" data-bs-toggle="collapse" data-bs-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 Diego Morgan, Dublin. Due Dec 28, 2026.</div></div></td>
</tr>
<tr>
<td>#ORD-5732</td>
<td>$784.26</td>
<td class="text-end"><button class="btn btn-sm btn-light border" type="button" data-bs-toggle="collapse" data-bs-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 Mateo Moreau, Valencia. Due Feb 8, 2027.</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-bs-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="looking-back-at-a-busy-season">
<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-bs-toggle="collapse" data-bs-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">
26.8k
</div>
<div class="small text-success">
<i class="bi bi-arrow-up" aria-hidden="true"></i> 4% 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-bs-toggle="collapse" data-bs-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">
Career coaches help with your CV, portfolio and interview practice. Learn on your schedule, with lessons that fit into a lunch break.
</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-bs-toggle="collapse" data-bs-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">
Every course is built around hands-on projects you can add to your portfolio.
</div>
</div>13Comments thread
Keep a feed short and let readers open the replies.
Clear prices, honest advice and no surprises along the way.
View 2 replies<p class="mb-1">Clear prices, honest advice and no surprises along the way.</p>
<a class="small" data-bs-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="Tariq Tanaka" class="rounded-circle flex-shrink-0" width="32" height="32">
<div class="bg-body-tertiary rounded p-2 small">
<strong>Tariq Tanaka</strong> We keep things simple, so you can focus on what matters to you.
</div>
</div>
<div class="d-flex gap-2 mb-2">
<img src="../assets/img/avatar-8.svg" alt="Kenji Ibrahim" class="rounded-circle flex-shrink-0" width="32" height="32">
<div class="bg-body-tertiary rounded p-2 small">
<strong>Kenji Ibrahim</strong> Start in minutes and get help from a real person whenever you need it.
</div>
</div>
</div>
</div>14Release notes
A compact version line that expands into the full change list.
- Mobile learning
- Mobile learning
- 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 4.3</span> <span class="badge text-bg-success">Stable</span>
<div class="small text-body-secondary">
Oct 3, 2026
</div>
</div>
<button class="btn btn-outline-primary btn-sm" type="button" data-bs-toggle="collapse" data-bs-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>Mobile learning</li>
<li>Mobile learning</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
- 8.5 kg
- Dimensions
- 29 x 37 x 11 cm
- Warranty
- 3 years
<button class="btn btn-outline-secondary w-100" type="button" data-bs-toggle="collapse" data-bs-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">8.5 kg</dd>
<dt class="col-sm-4">Dimensions</dt>
<dd class="col-sm-8">29 x 37 x 11 cm</dd>
<dt class="col-sm-4">Warranty</dt>
<dd class="col-sm-8 mb-0">3 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">Nimbus Labs</span>
<button class="btn btn-light" type="button" data-bs-toggle="collapse" data-bs-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 Nimbus Labs">
</div>
</div>
</div>17Onboarding checklist
Each checklist step expands to explain what to do.
We measure success by how many students come back and tell their friends.
Mentors review your projects and give feedback within two days.
Study groups and a friendly forum keep you motivated along the way.
<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-bs-toggle="collapse" data-bs-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">We measure success by how many students come back and tell their friends.</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-bs-toggle="collapse" data-bs-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">Mentors review your projects and give feedback within two days.</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-bs-toggle="collapse" data-bs-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">Study groups and a friendly forum keep you motivated along the way.</p>
</div>
</div>
</div>18Swap two panels
Two collapses sharing a class swap places: one hides while the other shows.
Read-only view: Thousands of students already trust us, and we work hard to keep it that way.
<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: Thousands of students already trust us, and we work hard to keep it that way.</p>
<button class="btn btn-primary btn-sm align-self-start" type="button" data-bs-toggle="collapse" data-bs-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">Guided learning paths take you from beginner to job-ready step by step.</textarea>
<button class="btn btn-success btn-sm align-self-start" type="button" data-bs-toggle="collapse" data-bs-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.
- Try the first lesson of any course for free before you decide.
- Our team has done this many times, so you never have to guess.
- Short quizzes after each lesson help new knowledge stick.
<ul class="list-group" style="max-width: 420px;">
<li class="list-group-item small"><i class="bi bi-bell" aria-hidden="true"></i> Try the first lesson of any course for free before you decide.</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">Our team has done this many times, so you never have to guess.</li><li class="list-group-item small text-body-secondary">Short quizzes after each lesson help new knowledge stick.</li></ul></div><button class="btn btn-link btn-sm w-100" type="button" data-bs-toggle="collapse" data-bs-target="#group-939" aria-expanded="false" aria-controls="group-939">Show 4 earlier</button></li>
</ul>20Nested collapse
A collapse inside another for drilling into details step by step.
Every detail is handled by people who care about getting it right.
- Design: $1,800.23
- Development: $8,788.20
- Marketing: $6,434.44
<button class="btn btn-outline-primary" type="button" data-bs-toggle="collapse" data-bs-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>Every detail is handled by people who care about getting it right.</p>
<button class="btn btn-sm btn-outline-secondary align-self-start" type="button" data-bs-toggle="collapse" data-bs-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: $1,800.23</li>
<li>Development: $8,788.20</li>
<li>Marketing: $6,434.44</li>
</ul>
</div>
</div>
</div>