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Bootstrap/site/content/docs/5.0/utilities/spacing.md

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---
layout: docs
title: Spacing
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description: Bootstrap includes a wide range of shorthand responsive margin and padding utility classes to modify an element's appearance.
group: utilities
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toc: true
---
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## How it works
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Assign responsive-friendly `margin` or `padding` values to an element or a subset of its sides with shorthand classes. Includes support for individual properties, all properties, and vertical and horizontal properties. Classes are built from a default Sass map ranging from `.25rem` to `3rem`.
## Notation
Spacing utilities that apply to all breakpoints, from `xs` to `xxl`, have no breakpoint abbreviation in them. This is because those classes are applied from `min-width: 0` and up, and thus are not bound by a media query. The remaining breakpoints, however, do include a breakpoint abbreviation.
The classes are named using the format `{property}{sides}-{size}` for `xs` and `{property}{sides}-{breakpoint}-{size}` for `sm`, `md`, `lg`, `xl`, and `xxl`.
Where *property* is one of:
- `m` - for classes that set `margin`
- `p` - for classes that set `padding`
Where *sides* is one of:
- `t` - for classes that set `margin-top` or `padding-top`
- `b` - for classes that set `margin-bottom` or `padding-bottom`
- `l` - for classes that set `margin-left` or `padding-left`
- `r` - for classes that set `margin-right` or `padding-right`
- `x` - for classes that set both `*-left` and `*-right`
- `y` - for classes that set both `*-top` and `*-bottom`
- blank - for classes that set a `margin` or `padding` on all 4 sides of the element
Where *size* is one of:
- `0` - for classes that eliminate the `margin` or `padding` by setting it to `0`
- `1` - (by default) for classes that set the `margin` or `padding` to `$spacer * .25`
- `2` - (by default) for classes that set the `margin` or `padding` to `$spacer * .5`
- `3` - (by default) for classes that set the `margin` or `padding` to `$spacer`
- `4` - (by default) for classes that set the `margin` or `padding` to `$spacer * 1.5`
- `5` - (by default) for classes that set the `margin` or `padding` to `$spacer * 3`
- `auto` - for classes that set the `margin` to auto
(You can add more sizes by adding entries to the `$spacers` Sass map variable.)
## Examples
Here are some representative examples of these classes:
{{< highlight scss >}}
.mt-0 {
margin-top: 0 !important;
}
.ml-1 {
margin-left: ($spacer * .25) !important;
}
.px-2 {
padding-left: ($spacer * .5) !important;
padding-right: ($spacer * .5) !important;
}
.p-3 {
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padding: $spacer !important;
}
{{< /highlight >}}
### Horizontal centering
Additionally, Bootstrap also includes an `.mx-auto` class for horizontally centering fixed-width block level content—that is, content that has `display: block` and a `width` set—by setting the horizontal margins to `auto`.
<div class="bd-example">
<div class="mx-auto" style="width: 200px; background-color: rgba(86,61,124,.15);">
Centered element
</div>
</div>
{{< highlight html >}}
<div class="mx-auto" style="width: 200px;">
Centered element
</div>
{{< /highlight >}}
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### Negative margin
In CSS, `margin` properties can utilize negative values (`padding` cannot). These negative margins are **disabled by default**, but can be enabled in Sass by setting `$enable-negative-margins: true`.
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The syntax is nearly the same as the default, positive margin utilities, but with the addition of `n` before the requested size. Here's an example class that's the opposite of `.mt-1`:
{{< highlight scss >}}
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.mt-n1 {
margin-top: -0.25rem !important;
}
{{< /highlight >}}