How to center a div with Bootstrap2?

Question

Bootstrap’s spans are floated to the left. All it takes to center them is override this behavior. I do this by adding this to my stylesheet:

.center {
     float: none;
     margin-left: auto;
     margin-right: auto;
}

If you have this class defined, just add it to the span and you’re good to go.

<div class="span7 center"> box </div>

Note that this custom center class must be defined after the bootstrap css. You could use !important but that isn’t recommended.