<script>

// ===== Scroll to Top ====
$(window).scroll(function() {

    if ($(this).scrollTop() >= 50) {        // If page is scrolled more than 50px
        $('#return-to-top').fadeIn(200);    // Fade in the arrow
    } else {
        $('#return-to-top').fadeOut(200);   // Else fade out the arrow
    }
});
$('#return-to-top').click(function() {      // When arrow is clicked
    $('body,html').animate({
        scrollTop : 0                       // Scroll to top of body
    }, 500);
});
// ===== ./Scroll to Top ====

</script> <div class=“fixed-action-btn back2top”>

<a  href="#" id="return-to-top" class="btn-floating btn-large waves-effect waves-light black"><i class="material-icons">keyboard_arrow_up</i></a>

</div>