Background

Background utilities paint an element with a theme colour, a subtle tint, the body surface or a gradient. Combine bg-{colour} with bg-opacity-* or the --ui-bg-opacity variable to fade it, and prefer the text-bg-* helpers or -emphasis text colours so contrast stays readable in light and dark mode.

1Theme colour backgrounds

bg-primary to bg-dark fill an element with a theme colour. Pair them with a readable text colour.

bg-primary

bg-secondary

bg-success

bg-danger

bg-warning

bg-info

bg-light

bg-dark

<div class="row g-2 small">
  <div class="col-6 col-md-3">
    <div class="bg-primary text-white rounded-md p-4">
      bg-primary
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="bg-secondary text-white rounded-md p-4">
      bg-secondary
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="bg-success text-white rounded-md p-4">
      bg-success
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="bg-danger text-white rounded-md p-4">
      bg-danger
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="bg-warning text-dark rounded-md p-4">
      bg-warning
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="bg-info text-dark rounded-md p-4">
      bg-info
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="bg-light text-dark rounded-md p-4 border">
      bg-light
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="bg-dark text-white rounded-md p-4">
      bg-dark
    </div>
  </div>
</div>

2Subtle backgrounds

The -subtle variants are soft tints that work in light and dark mode; use the matching -emphasis text colour.

bg-primary-subtle

bg-success-subtle

bg-warning-subtle

bg-danger-subtle

bg-info-subtle

<div class="grid gap-2">
  <div class="bg-primary-subtle text-primary-emphasis rounded-lg px-4 py-2">
    bg-primary-subtle
  </div>
  <div class="bg-success-subtle text-success-emphasis rounded-lg px-4 py-2">
    bg-success-subtle
  </div>
  <div class="bg-warning-subtle text-warning-emphasis rounded-lg px-4 py-2">
    bg-warning-subtle
  </div>
  <div class="bg-danger-subtle text-danger-emphasis rounded-lg px-4 py-2">
    bg-danger-subtle
  </div>
  <div class="bg-info-subtle text-info-emphasis rounded-lg px-4 py-2">
    bg-info-subtle
  </div>
</div>

3Body backgrounds

bg-body, bg-body-secondary and bg-body-tertiary follow the page surface and adapt to colour mode.

bg-body - the page itself

bg-body-secondary - side panels

bg-body-tertiary - wells and inputs

<div class="border rounded-xl overflow-hidden">
  <div class="bg-page p-4 border-b">
    <code>bg-body</code> - the page itself
  </div>
  <div class="bg-surface-2 p-4 border-b">
    <code>bg-body-secondary</code> - side panels
  </div>
  <div class="bg-surface-3 p-4">
    <code>bg-body-tertiary</code> - wells and inputs
  </div>
</div>

4Text and background together

text-bg-{colour} sets the background and a contrasting text colour in one class.

text-bg-primary text-bg-warning text-bg-info text-bg-light text-bg-dark

<div class="flex flex-wrap gap-2">
  <span class="text-bg-primary rounded-full px-4 py-1">text-bg-primary</span> <span class="text-bg-warning rounded-full px-4 py-1">text-bg-warning</span> <span class="text-bg-info rounded-full px-4 py-1">text-bg-info</span> <span class="text-bg-light rounded-full px-4 py-1 border">text-bg-light</span> <span class="text-bg-dark rounded-full px-4 py-1">text-bg-dark</span> 
</div>

5Background opacity steps

bg-opacity-10, -25, -50, -75 and -100 fade a theme background in fixed steps.

100

<div class="flex flex-wrap gap-2">
  <div class="bg-success/100 text-white rounded-lg p-4 small">
    100
  </div>
  <div class="bg-success/75 text-white rounded-lg p-4 small">
    75
  </div>
  <div class="bg-success/50 rounded-lg p-4 small">
    50
  </div>
  <div class="bg-success/25 rounded-lg p-4 small">
    25
  </div>
  <div class="bg-success/10 rounded-lg p-4 small">
    10
  </div>
</div>

6Gradient overlay

bg-gradient adds a soft white-to-transparent gradient on top of any bg-{colour}.

bg-primary bg-gradient

Local partners

bg-dark bg-gradient

Secure giving

<div class="row g-2">
  <div class="col-sm-6">
    <div class="bg-primary bg-gradient text-white rounded-xl p-6">
      <div class="font-semibold">
        bg-primary bg-gradient
      </div>
      <div class="small text-white/50">
        Local partners
      </div>
    </div>
  </div>
  <div class="col-sm-6">
    <div class="bg-dark bg-gradient text-white rounded-xl p-6">
      <div class="font-semibold">
        bg-dark bg-gradient
      </div>
      <div class="small text-white/50">
        Secure giving
      </div>
    </div>
  </div>
</div>

7Transparent background

bg-transparent removes a fill, useful when a component's default background must disappear.

bg-white

bg-transparent

<div class="bg-surface-3 rounded-lg p-4 flex flex-wrap gap-2">
  <div class="bg-white border rounded-md px-4 py-2 small">
    bg-white
  </div>
  <div class="bg-transparent border rounded-md px-4 py-2 small">
    bg-transparent
  </div>
  <button type="button" class="btn btn-light bg-transparent border-0"><i class="bi bi-three-dots" aria-hidden="true"></i> Ghost button</button>
</div>

8Black and white

bg-black and bg-white are fixed colours that do not change with colour mode, unlike bg-body.

bg-black

bg-white

<div class="flex rounded-lg overflow-hidden border">
  <div class="bg-black text-white flex-auto p-4 text-center small">
    bg-black
  </div>
  <div class="bg-white text-black flex-auto p-4 text-center small">
    bg-white
  </div>
</div>

9Highlighted table row

Background utilities on a table cell or row mark a selection without extra CSS.

Order	Customer	Total
#ORD-2081	Hana Moreau	$74.66
#INV-8821	Ava Haddad	$85.64
#INV-8413	Luna Harlow	$309.56

<div class="table-responsive">
  <table class="table table-sm mb-0 align-middle">
    <thead>
      <tr>
        <th scope="col">Order</th>
        <th scope="col">Customer</th>
        <th scope="col" class="text-end">Total</th>
      </tr>
    </thead>
    <tbody>
      <tr>
        <td>#ORD-2081</td>
        <td>Hana Moreau</td>
        <td class="text-end">$74.66</td>
      </tr>
      <tr>
        <td class="bg-primary-subtle">#INV-8821</td>
        <td class="bg-primary-subtle">Ava Haddad</td>
        <td class="bg-primary-subtle text-end font-semibold">$85.64</td>
      </tr>
      <tr>
        <td>#INV-8413</td>
        <td>Luna Harlow</td>
        <td class="text-end">$309.56</td>
      </tr>
    </tbody>
  </table>
</div>

10Feature icons on tinted circles

A subtle background with rounded-circle and fixed size gives each icon a soft colour badge.

Tax receipts

Secure giving

Tax receipts

<div class="row g-3">
  <div class="col-sm-4 flex gap-2 items-center">
    <span class="bg-primary-subtle text-primary rounded-full inline-flex items-center justify-center text-lg" style="width:44px;height:44px"><i class="bi bi-lightning-charge-fill" aria-hidden="true"></i></span><span class="small font-medium">Tax receipts</span>
  </div>
  <div class="col-sm-4 flex gap-2 items-center">
    <span class="bg-success-subtle text-success rounded-full inline-flex items-center justify-center text-lg" style="width:44px;height:44px"><i class="bi bi-shield-check" aria-hidden="true"></i></span><span class="small font-medium">Secure giving</span>
  </div>
  <div class="col-sm-4 flex gap-2 items-center">
    <span class="bg-danger-subtle text-danger rounded-full inline-flex items-center justify-center text-lg" style="width:44px;height:44px"><i class="bi bi-heart-fill" aria-hidden="true"></i></span><span class="small font-medium">Tax receipts</span>
  </div>
</div>

11Section bands

Alternating bg-body and bg-body-tertiary bands separate page sections.

Help us build a kinder world

A fast process helps projects moving forward from the very first day.

Small acts, big impact

The new volunteer network makes data easy to understand for teams of every size.

Join a community that cares

This elegant goal makes the whole team on the same page at a fair price.

<div class="border rounded-xl overflow-hidden">
  <section class="bg-page p-6">
    <h3 class="h6 mb-1">Help us build a kinder world</h3>
    <p class="small mb-0 text-muted">A fast process helps projects moving forward from the very first day.</p>
  </section>
  <section class="bg-surface-3 p-6">
    <h3 class="h6 mb-1">Small acts, big impact</h3>
    <p class="small mb-0 text-muted">The new volunteer network makes data easy to understand for teams of every size.</p>
  </section>
  <section class="bg-page p-6">
    <h3 class="h6 mb-1">Join a community that cares</h3>
    <p class="small mb-0 text-muted">This elegant goal makes the whole team on the same page at a fair price.</p>
  </section>
</div>

12Dark footer strip

bg-dark with text-white-50 and link-light builds a compact footer.

<footer class="bg-dark text-white/50 rounded-lg p-4 flex flex-col sm:flex-row justify-between gap-2 small">
  <span>&copy; Brand name 11</span> <span class="flex gap-4"><a href="#" class="link-light">Privacy</a><a href="#" class="link-light">Terms</a><a href="#" class="link-light">Contact</a></span> 
</footer>

13Alert-like message

A message strip built from bg-danger-subtle, a matching border and emphasis text.

Payment failed. Our clean water connects decisions quicker and clearer in just a few clicks.

<div class="bg-danger-subtle border border-danger/30 text-danger-emphasis rounded-lg p-4 flex gap-2" role="alert">
  <span class="text-lg"><i class="bi bi-exclamation-octagon-fill" aria-hidden="true"></i></span> 
  <div>
    <strong>Payment failed.</strong> <span class="small">Our clean water connects decisions quicker and clearer in just a few clicks.</span>
  </div>
</div>

14Background on hoverable list

List items with bg-body-tertiary for the active one; other rows stay on bg-body.

Inbox
Starred
Sent
Archive

<ul class="list-unstyled border rounded-lg mb-0 overflow-hidden" style="max-width:20rem">
  <li class="px-4 py-2 bg-page border-b"><i class="bi bi-inbox" aria-hidden="true"></i> Inbox</li>
  <li class="px-4 py-2 bg-surface-3 border-b font-semibold"><i class="bi bi-star-fill" aria-hidden="true"></i> Starred</li>
  <li class="px-4 py-2 bg-page border-b"><i class="bi bi-send" aria-hidden="true"></i> Sent</li>
  <li class="px-4 py-2 bg-page"><i class="bi bi-archive" aria-hidden="true"></i> Archive</li>
</ul>

15Progress made from backgrounds

A bg-body-secondary track and a bg-success fill with a width utility form a simple meter.

Storage75 of 100 GB

Seats5 of 20

<div class="grid gap-4">
  <div>
    <div class="flex justify-between small mb-1">
      <span>Storage</span><span>75 of 100 GB</span>
    </div>
    <div class="bg-surface-2 rounded-full" style="height:8px">
      <div class="bg-success rounded-full h-full w-3/4">
      </div>
    </div>
  </div>
  <div>
    <div class="flex justify-between small mb-1">
      <span>Seats</span><span>5 of 20</span>
    </div>
    <div class="bg-surface-2 rounded-full" style="height:8px">
      <div class="bg-warning rounded-full h-full w-1/4">
      </div>
    </div>
  </div>
</div>

16Pricing highlight

The recommended plan gets bg-primary and white text; the others stay on bg-body-tertiary.

Basic

$15.60

Pro

$36.41

Team

$81.71

<div class="row g-2 text-center">
  <div class="col-4">
    <div class="bg-surface-3 rounded-lg p-4">
      <div class="small">
        Basic
      </div>
      <div class="text-lg font-bold">
        $15.60
      </div>
    </div>
  </div>
  <div class="col-4">
    <div class="bg-primary text-white rounded-lg p-4">
      <div class="small">
        Pro
      </div>
      <div class="text-lg font-bold">
        $36.41
      </div>
    </div>
  </div>
  <div class="col-4">
    <div class="bg-surface-3 rounded-lg p-4">
      <div class="small">
        Team
      </div>
      <div class="text-lg font-bold">
        $81.71
      </div>
    </div>
  </div>
</div>

17Colour swatches

Square swatches with bg-{colour} and a caption below, as used in a style guide.

Primary

Secondary

Success

Warning

Surface

<div class="flex flex-wrap gap-4">
  <figure class="mb-0 text-center">
    <div class="bg-primary rounded-lg" style="width:56px;height:56px">
    </div>
    <figcaption class="small mt-1">Primary</figcaption>
  </figure>
  <figure class="mb-0 text-center">
    <div class="bg-secondary rounded-lg" style="width:56px;height:56px">
    </div>
    <figcaption class="small mt-1">Secondary</figcaption>
  </figure>
  <figure class="mb-0 text-center">
    <div class="bg-success rounded-lg" style="width:56px;height:56px">
    </div>
    <figcaption class="small mt-1">Success</figcaption>
  </figure>
  <figure class="mb-0 text-center">
    <div class="bg-warning rounded-lg" style="width:56px;height:56px">
    </div>
    <figcaption class="small mt-1">Warning</figcaption>
  </figure>
  <figure class="mb-0 text-center">
    <div class="bg-surface-2 border rounded-lg" style="width:56px;height:56px">
    </div>
    <figcaption class="small mt-1">Surface</figcaption>
  </figure>
</div>

18Card header and footer tints

bg-body-tertiary on the header and footer of a card, bg-body in the middle.

What's new in health

The new volunteer network connects time back in your day on any device.

Updated just now

<div class="border rounded-lg overflow-hidden" style="max-width:24rem">
  <div class="bg-surface-3 px-4 py-2 border-b font-semibold small">
    What&#39;s new in health
  </div>
  <div class="bg-page p-4 small">
    The new volunteer network connects time back in your day on any device.
  </div>
  <div class="bg-surface-3 px-4 py-2 border-t small text-muted">
    Updated just now
  </div>
</div>

19Image scrim with bg-black

A bg-black layer at reduced --ui-bg-opacity makes white text readable over a photo.

Join a community that cares

<div class="relative rounded-xl overflow-hidden" style="max-width:28rem">
  <img src="../assets/img/wide-5.svg" alt="Small acts, big impact" class="w-full block"> 
  <div class="absolute top-0 start-0 w-full h-full bg-black flex items-center justify-center" style="--ui-bg-opacity:.45">
    <span class="text-white text-lg font-semibold text-center px-4">Join a community that cares</span> 
  </div>
</div>

20Chat bubbles

Incoming messages on bg-body-tertiary, outgoing on bg-primary, each with a rounded corner set.

Our food relief connects you focused on what matters wherever you are.

Our animal rescue connects time back in your day from the very first day.

The new transparent reports gives complex tasks into simple steps without the usual hassle.

<div class="flex flex-col gap-2" style="max-width:24rem">
  <div class="self-start bg-surface-3 rounded-xl rounded-b-none px-4 py-2 small">
    Our food relief connects you focused on what matters wherever you are.
  </div>
  <div class="self-end bg-primary text-white rounded-xl rounded-b-none px-4 py-2 small">
    Our animal rescue connects time back in your day from the very first day.
  </div>
  <div class="self-start bg-surface-3 rounded-xl rounded-b-none px-4 py-2 small">
    The new transparent reports gives complex tasks into simple steps without the usual hassle.
  </div>
</div>