css hover not working with back top button

Question

I am using this: http://codyhouse.co/demo/back-to-top/

To add a back to top button. Thus far it works as advertised, but I am having an issue getting the hover to work.

In Chrome inspector when I force hover on .cd-top the css style does not turn on, and I can't imagine why as it does in the example. Basically there no change in opacity when hovered.

.no-touch .cd-top:hover {
  /*background-color: #FF9E00;*/
  opacity: 1;
}

You can view the page in question here

Js:

/***************************************************
      SCROLL FOR PORTFOLIO
***************************************************/
jQuery(document).ready(function($){
    // browser window scroll (in pixels) after which the "back to top" link is shown
    var offset = 300,
        //browser window scroll (in pixels) after which the "back to top" link opacity is reduced
        offset_opacity = 1200,
        //duration of the top scrolling animation (in ms)
        scroll_top_duration = 700,
        //grab the "back to top" link
        $back_to_top = $('.cd-top');

    //hide or show the "back to top" link
    $(window).scroll(function(){
        ( $(this).scrollTop() > offset ) ? $back_to_top.addClass('cd-is-visible') : $back_to_top.removeClass('cd-is-visible cd-fade-out');
        if( $(this).scrollTop() > offset_opacity ) { 
            $back_to_top.addClass('cd-fade-out');
        }
    });

    //smooth scroll to top
    $back_to_top.on('click', function(event){
        event.preventDefault();
        $('body,html').animate({
            scrollTop: 0 ,
            }, scroll_top_duration
        );
    });

});

Full CSS

.cd-top {
  display: inline-block;
  height: 40px;
  width: 40px;
  position: fixed;
  bottom: 100px;
  right: 10px;
  z-index: 10;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.05);
  /* image replacement properties */
  overflow: hidden;
  text-indent: 100%;
  white-space: nowrap;
  background: url(/images/cd-top-arrow.svg) no-repeat center 50%;
  visibility: hidden;
  opacity: 0;
  -webkit-transition: opacity .3s 0s, visibility 0s .3s;
  -moz-transition: opacity .3s 0s, visibility 0s .3s;
  transition: opacity .3s 0s, visibility 0s .3s;
}
.cd-top.cd-is-visible, .cd-top.cd-fade-out, .no-touch .cd-top:hover {
  -webkit-transition: opacity .3s 0s, visibility 0s 0s;
  -moz-transition: opacity .3s 0s, visibility 0s 0s;
  transition: opacity .3s 0s, visibility 0s 0s;
}
.cd-top.cd-is-visible {
  /* the button becomes visible */
  visibility: visible;
  opacity: 1;
}
.cd-top.cd-fade-out {
  /* if the user keeps scrolling down, the button is out of focus and becomes less visible */
  opacity: .5;
}
.no-touch .cd-top:hover {
  /*background-color: #FF9E00;*/
  opacity: 1;
}
@media only screen and (min-width: 768px) {
  .cd-top {
    right: 20px;
    bottom: 20px;
  }
}
@media only screen and (min-width: 1024px) {
  .cd-top {
    height: 60px;
    width: 60px;
    right: 30px;
    bottom: 30px;
  }
}

Answer 1

Remove .no-touch like so:

.cd-top:hover {
  /*background-color: #FF9E00;*/
  opacity: 1;
}

This will get the :hover to fire properly -- just be sure to add a starting opacity (eg 0.8) so you can see the effect.

Explanation: The Codyhouse example uses Modernizr , a feature detection library which adds a "no-touch" class to the HTML tag for non-touch-based devices such as your standard laptop. Conversely, "touch" is added for all touch-based devices. If you inspect the Codyhouse page, you'll see a ton of Modernizr-added classes in the HTML tag.