bootstrap spacing
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 $spacer defaults to 1rem