logo div effect like tisson theme

Hello, I need to set style.css and function.php in http://wescot.it/nuovo/ to have same style of tisson theme http://themes.muffingroup.com/tisson/

I try to use this code but do not work also in mobile mode.

style.css
.logo {
height: 200px!important;
width: 200px!important;
background-color:#fff!important;
padding:5px!important;
}
.logoop { opacity: 0 !important; }

function.php

<?php

function avia_custom_logo_app(){
?>
<script>
jQuery(window).scroll(function(){
if(jQuery(this).scrollTop() > 100) jQuery(‘.logo img’).addClass(‘logoop’);
if(jQuery(this).scrollTop() < 100) jQuery(‘.logo img’).removeClass(‘logoop’);
});
</script>