source/misc/embedded_libs/fmt-8.1.1/doc/bootstrap/mixins/center-block.less
browsing at commit = c8e0251f6827c9f9711f3b81e5279b9bc72ab0f2
// Center-align a block level element
.center-block() {
display: block;
margin-left: auto;
margin-right: auto;
}