How to show loading spinner after click on add to cart button [closed]

When the button is clicked it is given a class of loading which doesn’t appear to be handled.

You will have to find an icon in an iconfont (preferebly already loaded in your site i think its loading glyphicons) to use and add some css like below (Not tested, modify to suit)

Let me know if that helps.

button.add_to_cart_button.loading:after{
    position:absolute;
    top:0;
    left:0;
    width:100%;
    height:100%;
    font-family:"Glyphicons Halflings";
    content: "\e031";
    background: rgba( 255, 255, 255, 0.7 );
    text-align:center;
    line-height:34px;
}