btn to top scroll

js

js

$(window).on("scroll", function(){
    if ($(this).scrollTop() > 100) {
        $('.btn_scrollup').fadeIn();
    } else {
        $('.btn_scrollup').fadeOut();
    }
});

$('.btn_scrollup').on('click', function(){
    $("html, body").animate({ scrollTop: 0 }, 600);
    return false;
});


HTML

<a href="#" class="btn_scrollup">Scroll</a>

CSS

.btn_scrollup{
    width:40px;
    height:40px;
    opacity:0.3;
    position:fixed;
    bottom:50px;
    right:80px;
    display:none;
    text-indent:-9999px;
    background-color: red;
}