<button class="mantra-button mantra-primary-btn mantra-large-btn ">
 <i class="fa fa-shopping-cart "></i>Cart
</button>
<button class="mantra-button mantra-primary-btn ">
<i class="fa fa-facebook "></i>Facebook
</button>
<button class="mantra-button mantra-primary-btn mantra-small-btn ">
<i class="fa fa-share "></i>Share
</button>