.spinner{

    width:18px;

    height:18px;

    border:2px solid rgba(255,255,255,.4);

    border-top:2px solid #fff;

    border-radius:50%;

    display:none;

    animation:spin .8s linear infinite;

}

@keyframes spin{

    from{

        transform:rotate(0deg);

    }

    to{

        transform:rotate(360deg);

    }

}