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 - text-bg-primary picks the one that reads on your brand 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="text-bg-primary rounded-2 p-3">
      bg-primary
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="text-bg-secondary rounded-2 p-3">
      bg-secondary
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="bg-success text-white rounded-2 p-3">
      bg-success
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="bg-danger text-white rounded-2 p-3">
      bg-danger
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="bg-warning text-dark rounded-2 p-3">
      bg-warning
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="bg-info text-dark rounded-2 p-3">
      bg-info
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="bg-light text-dark rounded-2 p-3 border">
      bg-light
    </div>
  </div>
  <div class="col-6 col-md-3">
    <div class="text-bg-dark rounded-2 p-3">
      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="d-grid gap-2">
  <div class="bg-primary-subtle text-primary-emphasis rounded-3 px-3 py-2">
    bg-primary-subtle
  </div>
  <div class="bg-success-subtle text-success-emphasis rounded-3 px-3 py-2">
    bg-success-subtle
  </div>
  <div class="bg-warning-subtle text-warning-emphasis rounded-3 px-3 py-2">
    bg-warning-subtle
  </div>
  <div class="bg-danger-subtle text-danger-emphasis rounded-3 px-3 py-2">
    bg-danger-subtle
  </div>
  <div class="bg-info-subtle text-info-emphasis rounded-3 px-3 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-4 overflow-hidden">
  <div class="bg-body p-3 border-bottom">
    <code>bg-body</code> - the page itself
  </div>
  <div class="bg-body-secondary p-3 border-bottom">
    <code>bg-body-secondary</code> - side panels
  </div>
  <div class="bg-body-tertiary p-3">
    <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="d-flex flex-wrap gap-2">
  <span class="text-bg-primary rounded-pill px-3 py-1">text-bg-primary</span> <span class="text-bg-warning rounded-pill px-3 py-1">text-bg-warning</span> <span class="text-bg-info rounded-pill px-3 py-1">text-bg-info</span> <span class="text-bg-light rounded-pill px-3 py-1 border">text-bg-light</span> <span class="text-bg-dark rounded-pill px-3 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. White text needs the full colour; the labels sit under the lighter steps.

100

<div class="d-flex flex-wrap gap-3 small text-center">
  <div>
    <div class="bg-success bg-opacity-100 rounded-3 mb-1" style="width:4rem;height:3rem">
    </div>
    100
  </div>
  <div>
    <div class="bg-success bg-opacity-75 rounded-3 mb-1" style="width:4rem;height:3rem">
    </div>
    75
  </div>
  <div>
    <div class="bg-success bg-opacity-50 rounded-3 mb-1" style="width:4rem;height:3rem">
    </div>
    50
  </div>
  <div>
    <div class="bg-success bg-opacity-25 rounded-3 mb-1" style="width:4rem;height:3rem">
    </div>
    25
  </div>
  <div>
    <div class="bg-success bg-opacity-10 rounded-3 mb-1" style="width:4rem;height:3rem">
    </div>
    10
  </div>
</div>

6Gradient overlay

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

bg-primary bg-gradient

Open 24/7

bg-dark bg-gradient

Flexible plans

<div class="row g-2">
  <div class="col-sm-6">
    <div class="bg-primary bg-gradient text-white rounded-4 p-4">
      <div class="fw-semibold">
        bg-primary bg-gradient
      </div>
      <div class="small text-white-50">
        Open 24/7
      </div>
    </div>
  </div>
  <div class="col-sm-6">
    <div class="bg-dark bg-gradient text-white rounded-4 p-4">
      <div class="fw-semibold">
        bg-dark bg-gradient
      </div>
      <div class="small text-white-50">
        Flexible plans
      </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-body-tertiary rounded-3 p-3 d-flex flex-wrap gap-2">
  <div class="bg-white text-dark border rounded-2 px-3 py-2 small">
    bg-white
  </div>
  <div class="bg-transparent border rounded-2 px-3 py-2 small">
    bg-transparent
  </div>
  <button type="button" class="btn btn-light bg-transparent border-0 text-body"><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="d-flex rounded-3 overflow-hidden border">
  <div class="bg-black text-white flex-fill p-3 text-center small">
    bg-black
  </div>
  <div class="bg-white text-black flex-fill p-3 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
#PO-3658	Jonah Carter	$241.67
#ORD-2147	Samir Novak	$42.94
#ORD-1533	Maya Haddad	$270.89

<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>#PO-3658</td>
        <td>Jonah Carter</td>
        <td class="text-end">$241.67</td>
      </tr>
      <tr>
        <td class="bg-primary-subtle">#ORD-2147</td>
        <td class="bg-primary-subtle">Samir Novak</td>
        <td class="bg-primary-subtle text-end fw-semibold">$42.94</td>
      </tr>
      <tr>
        <td>#ORD-1533</td>
        <td>Maya Haddad</td>
        <td class="text-end">$270.89</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.

Progress tracking

Community events

<div class="row g-3">
  <div class="col-sm-4 d-flex gap-2 align-items-center">
    <span class="bg-primary-subtle text-primary rounded-circle d-inline-flex align-items-center justify-content-center fs-5" style="width:44px;height:44px"><i class="bi bi-lightning-charge-fill" aria-hidden="true"></i></span><span class="small fw-medium">Progress tracking</span>
  </div>
  <div class="col-sm-4 d-flex gap-2 align-items-center">
    <span class="bg-success-subtle text-success rounded-circle d-inline-flex align-items-center justify-content-center fs-5" style="width:44px;height:44px"><i class="bi bi-shield-check" aria-hidden="true"></i></span><span class="small fw-medium">Progress tracking</span>
  </div>
  <div class="col-sm-4 d-flex gap-2 align-items-center">
    <span class="bg-danger-subtle text-danger rounded-circle d-inline-flex align-items-center justify-content-center fs-5" style="width:44px;height:44px"><i class="bi bi-heart-fill" aria-hidden="true"></i></span><span class="small fw-medium">Community events</span>
  </div>
</div>

11Section bands

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

Feel at home in your gym

Every detail is handled by people who care about getting it right.

Train smarter, feel better

Start in minutes and get help from a real person whenever you need it.

Find the workout you will love

Thousands of members already trust us, and we work hard to keep it that way.

<div class="border rounded-4 overflow-hidden">
  <section class="bg-body p-4">
    <h3 class="h6 mb-1">Feel at home in your gym</h3>
    <p class="small mb-0 text-body-secondary">Every detail is handled by people who care about getting it right.</p>
  </section>
  <section class="bg-body-tertiary p-4">
    <h3 class="h6 mb-1">Train smarter, feel better</h3>
    <p class="small mb-0 text-body-secondary">Start in minutes and get help from a real person whenever you need it.</p>
  </section>
  <section class="bg-body p-4">
    <h3 class="h6 mb-1">Find the workout you will love</h3>
    <p class="small mb-0 text-body-secondary">Thousands of members already trust us, and we work hard to keep it that way.</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-3 p-3 d-flex flex-column flex-sm-row justify-content-between gap-2 small">
  <span>&copy; Lumenan Studio</span> <span class="d-flex gap-3"><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 team has done this many times, so you never have to guess.

<div class="bg-danger-subtle border border-danger-subtle text-danger-emphasis rounded-3 p-3 d-flex gap-2" role="alert">
  <span class="fs-5"><i class="bi bi-exclamation-octagon-fill" aria-hidden="true"></i></span> 
  <div>
    <strong>Payment failed.</strong> <span class="small">Our team has done this many times, so you never have to guess.</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-3 mb-0 overflow-hidden" style="max-width:20rem">
  <li class="px-3 py-2 bg-body border-bottom"><i class="bi bi-inbox-fill" aria-hidden="true"></i> Inbox</li>
  <li class="px-3 py-2 bg-body-tertiary border-bottom fw-semibold"><i class="bi bi-star-fill" aria-hidden="true"></i> Starred</li>
  <li class="px-3 py-2 bg-body border-bottom"><i class="bi bi-send-fill" aria-hidden="true"></i> Sent</li>
  <li class="px-3 py-2 bg-body"><i class="bi bi-archive-fill" 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="d-grid gap-3">
  <div>
    <div class="d-flex justify-content-between small mb-1">
      <span>Storage</span><span>75 of 100 GB</span>
    </div>
    <div class="bg-body-secondary rounded-pill" style="height:8px">
      <div class="bg-success rounded-pill h-100 w-75">
      </div>
    </div>
  </div>
  <div>
    <div class="d-flex justify-content-between small mb-1">
      <span>Seats</span><span>5 of 20</span>
    </div>
    <div class="bg-body-secondary rounded-pill" style="height:8px">
      <div class="bg-warning rounded-pill h-100 w-25">
      </div>
    </div>
  </div>
</div>

16Pricing highlight

The recommended plan gets text-bg-primary (the brand colour with the text colour that reads on it); the others stay on bg-body-tertiary.

Basic

$15.64

Pro

$23.33

Team

$66.68

<div class="row g-2 text-center">
  <div class="col-4">
    <div class="bg-body-tertiary rounded-3 p-3">
      <div class="small">
        Basic
      </div>
      <div class="fs-5 fw-bold">
        $15.64
      </div>
    </div>
  </div>
  <div class="col-4">
    <div class="text-bg-primary rounded-3 p-3">
      <div class="small">
        Pro
      </div>
      <div class="fs-5 fw-bold">
        $23.33
      </div>
    </div>
  </div>
  <div class="col-4">
    <div class="bg-body-tertiary rounded-3 p-3">
      <div class="small">
        Team
      </div>
      <div class="fs-5 fw-bold">
        $66.68
      </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="d-flex flex-wrap gap-3">
  <figure class="mb-0 text-center">
    <div class="bg-primary rounded-3" 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-3" 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-3" 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-3" style="width:56px;height:56px">
    </div>
    <figcaption class="small mt-1">Warning</figcaption>
  </figure>
  <figure class="mb-0 text-center">
    <div class="bg-body-secondary border rounded-3" 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.

HIIT twice a week: how hard is hard enough?

We measure success by how many members come back and tell their friends.

Updated just now

<div class="border rounded-3 overflow-hidden" style="max-width:24rem">
  <div class="bg-body-tertiary px-3 py-2 border-bottom fw-semibold small">
    HIIT twice a week: how hard is hard enough?
  </div>
  <div class="bg-body p-3 small">
    We measure success by how many members come back and tell their friends.
  </div>
  <div class="bg-body-tertiary px-3 py-2 border-top small text-body-secondary">
    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.

Real coaches, real results

<div class="position-relative rounded-4 overflow-hidden" style="max-width:28rem">
  <img src="https://images.unsplash.com/photo-1541534741688-6078c6bfb5c5?auto=format&fit=crop&w=1600&h=700&q=70" alt="Fitness for every body" class="w-100 d-block"> 
  <div class="position-absolute top-0 start-0 w-100 h-100 bg-black d-flex align-items-center justify-content-center" style="--ui-bg-opacity:.45">
    <span class="text-white fs-5 fw-semibold text-center px-3">Real coaches, real results</span> 
  </div>
</div>

20Chat bubbles

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

We keep things simple, so you can focus on what matters to you.

Community events keep you motivated, from fun runs to workshops.

More than sixty classes a week, from sunrise yoga to late-night spin.

<div class="d-flex flex-column gap-2" style="max-width:24rem">
  <div class="align-self-start bg-body-tertiary rounded-4 rounded-bottom-0 px-3 py-2 small">
    We keep things simple, so you can focus on what matters to you.
  </div>
  <div class="align-self-end text-bg-primary rounded-4 rounded-bottom-0 px-3 py-2 small">
    Community events keep you motivated, from fun runs to workshops.
  </div>
  <div class="align-self-start bg-body-tertiary rounded-4 rounded-bottom-0 px-3 py-2 small">
    More than sixty classes a week, from sunrise yoga to late-night spin.
  </div>
</div>