Flex
Flex utilities control flexbox layouts: direction, wrapping, alignment on both axes, growing, shrinking, order and gaps. Every utility has responsive variants such as flex-md-row or justify-content-lg-between, so one set of markup can stack on phones and spread out on larger screens.
1Direction
flex-row is the default, flex-row-reverse flips it, flex-column stacks items.
123123123<div class="d-grid gap-2">
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 flex-row">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">1</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">2</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">3</code>
</div>
</div>
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 flex-row-reverse">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">1</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">2</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">3</code>
</div>
</div>
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 flex-column">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">1</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">2</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">3</code>
</div>
</div>
</div>2Justify content
start, center, end, between, around and evenly distribute free space on the main axis.
ABABABABABAB<div class="d-grid gap-2">
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 justify-content-start">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">A</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">B</code>
</div>
</div>
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 justify-content-center">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">A</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">B</code>
</div>
</div>
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 justify-content-end">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">A</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">B</code>
</div>
</div>
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 justify-content-between">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">A</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">B</code>
</div>
</div>
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 justify-content-around">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">A</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">B</code>
</div>
</div>
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 justify-content-evenly">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">A</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">B</code>
</div>
</div>
</div>3Align items
align-items-start, -center, -end and -stretch align items on the cross axis.
startxstartxstartxstartx<div class="row g-2">
<div class="col-6 col-md-3">
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 align-items-start" style="height:100px">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">start</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">x</code>
</div>
</div>
</div>
<div class="col-6 col-md-3">
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 align-items-center" style="height:100px">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">start</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">x</code>
</div>
</div>
</div>
<div class="col-6 col-md-3">
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 align-items-end" style="height:100px">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">start</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">x</code>
</div>
</div>
</div>
<div class="col-6 col-md-3">
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 align-items-stretch" style="height:100px">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">start</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">x</code>
</div>
</div>
</div>
</div>4Align self
align-self-* moves a single item on the cross axis.
startcenterendstretch<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2" style="height:120px">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center align-self-start">
<code class="small">start</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center align-self-center">
<code class="small">center</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center align-self-end">
<code class="small">end</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center align-self-stretch">
<code class="small">stretch</code>
</div>
</div>5Fill and grow
flex-fill shares space equally, flex-grow-1 takes the remaining space.
flex-fillflex-fill wider textfillautoflex-grow-1auto<div class="d-grid gap-2">
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center flex-fill">
<code class="small">flex-fill</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center flex-fill">
<code class="small">flex-fill wider text</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center flex-fill">
<code class="small">fill</code>
</div>
</div>
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">auto</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center flex-grow-1">
<code class="small">flex-grow-1</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">auto</code>
</div>
</div>
</div>6Shrink
flex-shrink-0 keeps an item at its size while the other one shrinks.
flex-shrink-0flex-shrink-1 - Three days of keynotes, hands-on workshops and evening meetups.<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center flex-shrink-0" style="width:140px">
<code class="small">flex-shrink-0</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center flex-shrink-1 text-truncate">
<code class="small">flex-shrink-1 - Three days of keynotes, hands-on workshops and evening meetups.</code>
</div>
</div>7Auto margins
ms-auto pushes an item and everything after it to the end.
<div class="d-flex align-items-center gap-2 border rounded-3 px-3 py-2">
<span class="fw-bold">Opal</span> <a href="#" class="small link-body-emphasis">Docs</a> <a href="#" class="small link-body-emphasis">Blog</a>
<button type="button" class="btn btn-sm btn-primary ms-auto">Sign in</button>
</div>8Wrap
flex-wrap lets items move to a new line; flex-nowrap keeps one line.
itemitemitemitemitemitemitemitemitemitemitemitemitemitemitemitemitemitemitemitem<div class="d-grid gap-2">
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 flex-wrap">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
</div>
<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2 flex-nowrap overflow-x-auto">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">item</code>
</div>
</div>
</div>9Order
order-* changes the visual order without changing the markup.
first in markup, order-3second, order-1third, order-2<div class="d-flex gap-2 bg-body-tertiary rounded-3 p-2">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center order-3">
<code class="small">first in markup, order-3</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center order-1">
<code class="small">second, order-1</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center order-2">
<code class="small">third, order-2</code>
</div>
</div>10Row gap and column gap
row-gap-* and column-gap-* set the two gaps separately.
row-gap-4column-gap-1cdefghijkl<div class="d-flex flex-wrap row-gap-4 column-gap-1 bg-body-tertiary rounded-3 p-2">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">row-gap-4</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">column-gap-1</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">c</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">d</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">e</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">f</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">g</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">h</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">i</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">j</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">k</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">l</code>
</div>
</div>11Responsive direction
flex-column flex-sm-row: a sign-up form stacks on phones and sits in one row from sm.
<div class="d-flex flex-column flex-sm-row gap-2" style="max-width:30rem">
<label class="visually-hidden" for="ut-mail-1250">Email</label>
<input id="ut-mail-1250" type="email" class="form-control" placeholder="you@example.com">
<button type="button" class="btn btn-primary text-nowrap">Subscribe</button>
</div>12Media list
Each row is d-flex with an icon box that never shrinks.
- Mobile agendaWe measure success by how many attendees come back and tell their friends.
- World-class speakersVirtual passes let you join the main stage live from anywhere.
<ul class="list-unstyled mb-0 d-grid gap-3">
<li class="d-flex gap-3"><span class="flex-shrink-0 bg-primary-subtle text-primary rounded-3 p-2 fs-5 lh-1"><i class="bi bi-lightning-charge-fill" aria-hidden="true"></i></span><div><div class="fw-semibold">Mobile agenda</div><div class="small text-body-secondary">We measure success by how many attendees come back and tell their friends.</div></div></li>
<li class="d-flex gap-3"><span class="flex-shrink-0 bg-success-subtle text-success rounded-3 p-2 fs-5 lh-1"><i class="bi bi-shield-check" aria-hidden="true"></i></span><div><div class="fw-semibold">World-class speakers</div><div class="small text-body-secondary">Virtual passes let you join the main stage live from anywhere.</div></div></li>
</ul>13Sticky footer in a card
A flex-column card with flex-grow-1 body keeps the button at the bottom regardless of text length.
Every attendee receives a certificate of participation.
OpenEarly bird tickets save you up to forty percent until the end of the month. More than eighty speakers share what they have learned the hard way. The networking app helps you meet the right people before you arrive.
Open<div class="row g-3">
<div class="col-6">
<div class="d-flex flex-column border rounded-3 p-3 h-100">
<div class="fw-semibold">
A guide to the city for visiting attendees
</div>
<p class="small flex-grow-1">Every attendee receives a certificate of participation.</p>
<a href="#" class="btn btn-sm btn-outline-primary">Open</a>
</div>
</div>
<div class="col-6">
<div class="d-flex flex-column border rounded-3 p-3 h-100">
<div class="fw-semibold">
Five things we learned this year
</div>
<p class="small flex-grow-1">Early bird tickets save you up to forty percent until the end of the month. More than eighty speakers share what they have learned the hard way. The networking app helps you meet the right people before you arrive.</p>
<a href="#" class="btn btn-sm btn-outline-primary">Open</a>
</div>
</div>
</div>14Align content
align-content-* distributes wrapped lines in a taller container.
align-content-betweenbcdefghij<div class="d-flex flex-wrap align-content-between gap-2 bg-body-tertiary rounded-3 p-2" style="height:160px">
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">align-content-between</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">b</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">c</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">d</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">e</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">f</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">g</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">h</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">i</code>
</div>
<div class="bg-primary-subtle border border-primary-subtle rounded-2 p-2 text-center">
<code class="small">j</code>
</div>
</div>15Baseline alignment
align-items-baseline lines up text of different sizes on its baseline.
<div class="d-flex align-items-baseline gap-2">
<span class="display-6 fw-bold">$23.93</span><span class="text-body-secondary">/ month</span><span class="small text-success">billed yearly</span>
</div>16Horizontal stack
hstack is a shortcut for a centred flex row with gap.
<div class="hstack gap-2 border rounded-3 p-2">
<span class="badge text-bg-primary">how-to</span> <span class="small">What our attendees asked us most</span>
<div class="vr ms-auto">
</div>
<button type="button" class="btn btn-sm btn-light">Edit</button>
</div>17Vertical stack
vstack is a flex column with gap: quick form or card layouts.
<div class="vstack gap-2 border rounded-3 p-3" style="max-width:20rem">
<div class="fw-semibold">
Where great ideas meet
</div>
<div class="small text-body-secondary">
Every session is recorded, so you can catch up on anything you missed.
</div>
<button type="button" class="btn btn-primary btn-sm">Join waitlist</button>
</div>18Responsive justify
justify-content-center justify-content-md-between centres on phones and spreads from md.
<div class="d-flex flex-wrap justify-content-center justify-content-md-between align-items-center gap-2 border rounded-3 p-3">
<span class="small text-body-secondary">Showing 1-10 of 175</span>
<div class="d-flex gap-1">
<button type="button" class="btn btn-sm btn-light border">Prev</button>
<button type="button" class="btn btn-sm btn-light border">Next</button>
</div>
</div>19Equal width columns with flex-fill
Navigation tabs share the row equally with flex-fill and text-center.
<nav class="d-flex border rounded-3 overflow-hidden" aria-label="Period">
<a href="#" class="flex-fill text-center py-2 text-bg-primary text-decoration-none" aria-current="page">Day</a> <a href="#" class="flex-fill text-center py-2 link-body-emphasis text-decoration-none border-start">Week</a> <a href="#" class="flex-fill text-center py-2 link-body-emphasis text-decoration-none border-start">Month</a> <a href="#" class="flex-fill text-center py-2 link-body-emphasis text-decoration-none border-start">Year</a>
</nav>20Reverse on large screens
flex-column flex-lg-row-reverse: on large screens the image moves to the right.
Three days that change how you work
We keep things simple, so you can focus on what matters to you. Clear prices, honest advice and no surprises along the way.
<div class="d-flex flex-column flex-lg-row-reverse gap-3 align-items-lg-center">
<img src="https://images.unsplash.com/photo-1769755409781-9e8924c57362?auto=format&fit=crop&w=1200&h=800&q=70" alt="Big ideas, small rooms, real conversations" class="rounded-4 w-100" style="max-width:20rem">
<div>
<h3 class="h5 fw-semibold">Three days that change how you work</h3>
<p class="small text-body-secondary mb-0">We keep things simple, so you can focus on what matters to you. Clear prices, honest advice and no surprises along the way.</p>
</div>
</div>