Positioning button-block at the centre

hi, i have been struggling with positioning ionic button block in the centre.
here is the HTML snippet for it.
<div class="row row-full"> <div class="col col-full"> <button type="submit" class="button button-block button-positive" >{{'LOGIN' | translate}}</button> </div> </div>indent preformatted text by 4 spaces
can some one help me out in achieving it, thank you very much in advance.image