Vertically align button in column

Question

I'm trying to center my button vertically, but isn't working:

HTML:

<div class="col-md-6 text-right">
    <a class="btn btn-small btn-gray" ui-sref="login">Start Session</a>
</div>

CSS:

.btn {
    vertical-align: middle;
}

Answer 1

Possible duplicate of How to vertical align middle a button in a dynamic div

But, I think you need to just add

display:inline-block;

to your .btn CSS.