Also add v4.5.0 in versions and keep README.md pointing to v4.5.0 so that there are no broken stuff.
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layout | title | description | group | toc |
---|---|---|---|---|
docs | Spacing | Bootstrap includes a wide range of shorthand responsive margin and padding utility classes to modify an element's appearance. | utilities | true |
How it works
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 setmargin
p
- for classes that setpadding
Where sides is one of:
t
- for classes that setmargin-top
orpadding-top
b
- for classes that setmargin-bottom
orpadding-bottom
l
- for classes that setmargin-left
orpadding-left
r
- for classes that setmargin-right
orpadding-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
orpadding
on all 4 sides of the element
Where size is one of:
0
- for classes that eliminate themargin
orpadding
by setting it to0
1
- (by default) for classes that set themargin
orpadding
to$spacer * .25
2
- (by default) for classes that set themargin
orpadding
to$spacer * .5
3
- (by default) for classes that set themargin
orpadding
to$spacer
4
- (by default) for classes that set themargin
orpadding
to$spacer * 1.5
5
- (by default) for classes that set themargin
orpadding
to$spacer * 3
auto
- for classes that set themargin
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 { 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
.
{{< highlight html >}}
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
.
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 >}} .mt-n1 { margin-top: -0.25rem !important; } {{< /highlight >}}