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.
<div class="row g-2 small">
<div class="col-6 col-md-3">
<div class="bg-primary text-white rounded-2 p-3">
bg-primary
</div>
</div>
<div class="col-6 col-md-3">
<div class="bg-secondary text-white 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="bg-dark text-white 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.
<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 itselfbg-body-secondary - side panelsbg-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.
<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.
<div class="d-flex flex-wrap gap-2">
<div class="bg-success bg-opacity-100 text-white rounded-3 p-3 small">
100
</div>
<div class="bg-success bg-opacity-75 text-white rounded-3 p-3 small">
75
</div>
<div class="bg-success bg-opacity-50 rounded-3 p-3 small">
50
</div>
<div class="bg-success bg-opacity-25 rounded-3 p-3 small">
25
</div>
<div class="bg-success bg-opacity-10 rounded-3 p-3 small">
10
</div>
</div>6Gradient overlay
bg-gradient adds a soft white-to-transparent gradient on top of any bg-{colour}.
<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">
Flexible plans
</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">
Open 24/7
</div>
</div>
</div>
</div>7Transparent background
bg-transparent removes a fill, useful when a component's default background must disappear.
<div class="bg-body-tertiary rounded-3 p-3 d-flex flex-wrap gap-2">
<div class="bg-white 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"><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.
<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 |
|---|---|---|
| #ORD-4790 | Freya Ortega | $226.35 |
| #PO-2853 | Luna Whitaker | $325.44 |
| #PO-1169 | Ethan Tanaka | $189.26 |
<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-4790</td>
<td>Freya Ortega</td>
<td class="text-end">$226.35</td>
</tr>
<tr>
<td class="bg-primary-subtle">#PO-2853</td>
<td class="bg-primary-subtle">Luna Whitaker</td>
<td class="bg-primary-subtle text-end fw-semibold">$325.44</td>
</tr>
<tr>
<td>#PO-1169</td>
<td>Ethan Tanaka</td>
<td class="text-end">$189.26</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.
<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">Community events</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">Certified coaches</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">Progress tracking</span>
</div>
</div>11Section bands
Alternating bg-body and bg-body-tertiary bands separate page sections.
Train smarter, feel better
This powerful workflow turns results you can measure on any device.
Train smarter, feel better
The new open 24/7 brings customers coming back all year round.
Your fitness journey starts now
A elegant idea brings results you can measure from the very first day.
<div class="border rounded-4 overflow-hidden">
<section class="bg-body p-4">
<h3 class="h6 mb-1">Train smarter, feel better</h3>
<p class="small mb-0 text-body-secondary">This powerful workflow turns results you can measure on any device.</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">The new open 24/7 brings customers coming back all year round.</p>
</section>
<section class="bg-body p-4">
<h3 class="h6 mb-1">Your fitness journey starts now</h3>
<p class="small mb-0 text-body-secondary">A elegant idea brings results you can measure from the very first day.</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>© Brand name 18</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.
<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">This simple project keeps time back in your day at a fair price.</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" 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" aria-hidden="true"></i> Sent</li>
<li class="px-3 py-2 bg-body"><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.
<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 bg-primary and white text; the others stay on bg-body-tertiary.
<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">
$11.39
</div>
</div>
</div>
<div class="col-4">
<div class="bg-primary text-white rounded-3 p-3">
<div class="small">
Pro
</div>
<div class="fs-5 fw-bold">
$33.69
</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">
$89.42
</div>
</div>
</div>
</div>17Colour swatches
Square swatches with bg-{colour} and a caption below, as used in a style guide.
<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.
<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">
Inside the simple workflow
</div>
<div class="bg-body p-3 small">
A elegant workflow helps results you can measure from the very first day.
</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.
<div class="position-relative rounded-4 overflow-hidden" style="max-width:28rem">
<img src="../assets/img/wide-3.svg" alt="Move more, stress less" 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">Stronger every single day</span>
</div>
</div>20Chat bubbles
Incoming messages on bg-body-tertiary, outgoing on bg-primary, each with a rounded corner set.
<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">
Our nutrition plans guides the whole team on the same page at a fair price.
</div>
<div class="align-self-end bg-primary text-white rounded-4 rounded-bottom-0 px-3 py-2 small">
This honest routine keeps results you can measure all year round.
</div>
<div class="align-self-start bg-body-tertiary rounded-4 rounded-bottom-0 px-3 py-2 small">
This flexible routine gives every detail in view from the very first day.
</div>
</div>