Spacing

Use responsive margin and padding utility classes to modify an element's appearance.

Use margin or padding values to an element. It 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 utility classes that apply to all breakpoints, from xs to xl, have no breakpoint abbreviation in them because those classes are applied from min-width: 0; and up, and thus are not bound by a media query. The remaining breakpoints 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, and xl.

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.

Below are some examples of these classes.

.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;
}

Horizontal centering

Use .mx-auto class which sets horizontal margins to auto for horizontally centering fixed-width block level content(content that has display: block and a width).

<div class="mx-auto" style="width: 200px;">
  Centered element
</div>