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.

1

2

3

1

2

3

1

2

3

<div class="grid gap-2">
  <div class="flex gap-2 bg-surface-3 rounded-lg p-2 flex-row">
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">1</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">2</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">3</code>
    </div>
  </div>
  <div class="flex gap-2 bg-surface-3 rounded-lg p-2 flex-row-reverse">
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">1</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">2</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">3</code>
    </div>
  </div>
  <div class="flex gap-2 bg-surface-3 rounded-lg p-2 flex-col">
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">1</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">2</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md 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.

A

B

A

B

A

B

A

B

A

B

A

B

<div class="grid gap-2">
  <div class="flex gap-2 bg-surface-3 rounded-lg p-2 justify-start">
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">A</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">B</code>
    </div>
  </div>
  <div class="flex gap-2 bg-surface-3 rounded-lg p-2 justify-center">
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">A</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">B</code>
    </div>
  </div>
  <div class="flex gap-2 bg-surface-3 rounded-lg p-2 justify-end">
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">A</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">B</code>
    </div>
  </div>
  <div class="flex gap-2 bg-surface-3 rounded-lg p-2 justify-between">
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">A</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">B</code>
    </div>
  </div>
  <div class="flex gap-2 bg-surface-3 rounded-lg p-2 justify-around">
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">A</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">B</code>
    </div>
  </div>
  <div class="flex gap-2 bg-surface-3 rounded-lg p-2 justify-evenly">
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">A</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md 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.

start

x

start

x

start

x

start

x

<div class="row g-2">
  <div class="col-6 col-md-3">
    <div class="flex gap-2 bg-surface-3 rounded-lg p-2 items-start" style="height:100px">
      <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
        <code class="small">start</code>
      </div>
      <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
        <code class="small">x</code>
      </div>
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="flex gap-2 bg-surface-3 rounded-lg p-2 items-center" style="height:100px">
      <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
        <code class="small">start</code>
      </div>
      <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
        <code class="small">x</code>
      </div>
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="flex gap-2 bg-surface-3 rounded-lg p-2 items-end" style="height:100px">
      <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
        <code class="small">start</code>
      </div>
      <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
        <code class="small">x</code>
      </div>
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="flex gap-2 bg-surface-3 rounded-lg p-2 items-stretch" style="height:100px">
      <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
        <code class="small">start</code>
      </div>
      <div class="bg-primary-subtle border border-primary/30 rounded-md 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.

start

center

end

stretch

<div class="flex gap-2 bg-surface-3 rounded-lg p-2" style="height:120px">
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center self-start">
    <code class="small">start</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center self-center">
    <code class="small">center</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center self-end">
    <code class="small">end</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center 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-fill

flex-fill wider text

fill

auto

flex-grow-1

auto

<div class="grid gap-2">
  <div class="flex gap-2 bg-surface-3 rounded-lg p-2">
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center flex-auto">
      <code class="small">flex-fill</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center flex-auto">
      <code class="small">flex-fill wider text</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center flex-auto">
      <code class="small">fill</code>
    </div>
  </div>
  <div class="flex gap-2 bg-surface-3 rounded-lg p-2">
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">auto</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center grow">
      <code class="small">flex-grow-1</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md 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-0

flex-shrink-1 - Our specialists take time to listen and explain every step of your treatment.

<div class="flex gap-2 bg-surface-3 rounded-lg p-2">
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center shrink-0" style="width:140px">
    <code class="small">flex-shrink-0</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center shrink truncate">
    <code class="small">flex-shrink-1 - Our specialists take time to listen and explain every step of your treatment.</code>
  </div>
</div>

7Auto margins

ms-auto pushes an item and everything after it to the end.

Umbra Docs Blog

<div class="flex items-center gap-2 border rounded-lg px-4 py-2">
  <span class="font-bold">Umbra</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.

item

<div class="grid gap-2">
  <div class="flex gap-2 bg-surface-3 rounded-lg p-2 flex-wrap">
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
  </div>
  <div class="flex gap-2 bg-surface-3 rounded-lg p-2 flex-nowrap overflow-x-auto">
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
      <code class="small">item</code>
    </div>
    <div class="bg-primary-subtle border border-primary/30 rounded-md 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-3

second, order-1

third, order-2

<div class="flex gap-2 bg-surface-3 rounded-lg p-2">
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center order-3">
    <code class="small">first in markup, order-3</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center order-1">
    <code class="small">second, order-1</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md 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-4

column-gap-1

c

d

e

f

g

h

i

j

k

l

<div class="flex flex-wrap gap-y-6 gap-x-1 bg-surface-3 rounded-lg p-2">
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">row-gap-4</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">column-gap-1</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">c</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">d</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">e</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">f</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">g</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">h</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">i</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">j</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">k</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md 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="flex flex-col sm:flex-row gap-2" style="max-width:30rem">
  <label class="sr-only" 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 whitespace-nowrap">Subscribe</button>
</div>

12Media list

Each row is d-flex with an icon box that never shrinks.

Insurance friendly
Modern equipment means faster diagnoses and more comfortable treatment.
Same-day appointments
We listen first, then build a plan around what you actually need.

<ul class="list-unstyled mb-0 grid gap-4">
  <li class="flex gap-4"><span class="shrink-0 bg-primary-subtle text-primary-ink rounded-lg p-2 text-lg leading-none"><i class="bi bi-lightning-charge-fill" aria-hidden="true"></i></span><div><div class="font-semibold">Insurance friendly</div><div class="small text-muted">Modern equipment means faster diagnoses and more comfortable treatment.</div></div></li>
  <li class="flex gap-4"><span class="shrink-0 bg-success-subtle text-success-emphasis rounded-lg p-2 text-lg leading-none"><i class="bi bi-shield-check" aria-hidden="true"></i></span><div><div class="font-semibold">Same-day appointments</div><div class="small text-muted">We listen first, then build a plan around what you actually need.</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.

Staying active after an injury

Children are welcome, and our paediatric team knows how to make them smile.

Open

Looking back at a busy season

Same-day appointments are available for urgent needs on weekdays. Our team has done this many times, so you never have to guess. Start in minutes and get help from a real person whenever you need it.

Open

<div class="row g-3">
  <div class="col-6">
    <div class="flex flex-col border rounded-lg p-4 h-full">
      <div class="font-semibold">
        Staying active after an injury
      </div>
      <p class="small grow">Children are welcome, and our paediatric team knows how to make them smile.</p>
      <a href="#" class="btn btn-sm btn-outline-primary">Open</a>
    </div>
  </div>
  <div class="col-6">
    <div class="flex flex-col border rounded-lg p-4 h-full">
      <div class="font-semibold">
        Looking back at a busy season
      </div>
      <p class="small grow">Same-day appointments are available for urgent needs on weekdays. Our team has done this many times, so you never have to guess. Start in minutes and get help from a real person whenever you need it.</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-between

b

c

d

e

f

g

h

i

j

<div class="flex flex-wrap content-between gap-2 bg-surface-3 rounded-lg p-2" style="height:160px">
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">align-content-between</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">b</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">c</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">d</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">e</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">f</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">g</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">h</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md p-2 text-center">
    <code class="small">i</code>
  </div>
  <div class="bg-primary-subtle border border-primary/30 rounded-md 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.

$28.29/ monthbilled yearly

<div class="flex items-baseline gap-2">
  <span class="display-6 font-bold">$28.29</span><span class="text-muted">/ month</span><span class="small text-success-emphasis">billed yearly</span> 
</div>

16Horizontal stack

hstack is a shortcut for a centred flex row with gap.

community When to choose a video consultation

<div class="hstack gap-2 border rounded-lg p-2">
  <span class="badge text-bg-primary">community</span> <span class="small">When to choose a video consultation</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.

Healthy smiles start here

Book online in two minutes and see a doctor as soon as today.

<div class="vstack gap-2 border rounded-lg p-4" style="max-width:20rem">
  <div class="font-semibold">
    Healthy smiles start here
  </div>
  <div class="small text-muted">
    Book online in two minutes and see a doctor as soon as today.
  </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.

Showing 1-10 of 260

<div class="flex flex-wrap justify-center md:justify-between items-center gap-2 border rounded-lg p-4">
  <span class="small text-muted">Showing 1-10 of 260</span> 
  <div class="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="flex border rounded-lg overflow-hidden" aria-label="Period">
  <a href="#" class="flex-auto text-center py-2 text-bg-primary no-underline" aria-current="page">Day</a> <a href="#" class="flex-auto text-center py-2 link-body-emphasis no-underline border-s">Week</a> <a href="#" class="flex-auto text-center py-2 link-body-emphasis no-underline border-s">Month</a> <a href="#" class="flex-auto text-center py-2 link-body-emphasis no-underline border-s">Year</a> 
</nav>

20Reverse on large screens

flex-column flex-lg-row-reverse: on large screens the image moves to the right.

Expert doctors, gentle care

Family plans cover check-ups and vaccinations for everyone under one roof. We keep things simple, so you can focus on what matters to you.

<div class="flex flex-col lg:flex-row-reverse gap-4 lg:items-center">
  <img src="https://images.unsplash.com/photo-1606318313647-137d1f3b4d3c?auto=format&fit=crop&w=1200&h=800&q=70" alt="Book a doctor in minutes" class="rounded-xl w-full" style="max-width:20rem"> 
  <div>
    <h3 class="h5 font-semibold">Expert doctors, gentle care</h3>
    <p class="small text-muted mb-0">Family plans cover check-ups and vaccinations for everyone under one roof. We keep things simple, so you can focus on what matters to you.</p>
  </div>
</div>