Nav slide up & down

CSS

#header-scroll-up {
position: fixed; /* Makes it stick */
top: 0; /* Stay on top */
width: 100%; /* Full width */
transition: top 0.3s; /* Transition effect when sliding down (and up) */
z-index:20; /* added because the BB number counter module appeared over the header */
}

.admin-bar #header-scroll-up
{
margin-top: 32px; /* added so the WP bar did not obscure the header when logged in */
}

#fl-main-content
{
margin-top: 80px; /* The space need after the header and the main content */
}

.fl-builder-content[data-type="header"].fl-theme-builder-header-shrink IMG
{
max-height: 30px !important; /* shinks the logo image if using Beaver Themer's
shrink option. You could swap the IMG select for something else you want to make smaller */

}
.fl-theme-builder-header
{
background-color: #3B4736; /* Because the transition effect on the header you can see a flash
of the site's background color. This mask this by adding a matching header area background.*/
}

JQuery

/* When the user scrolls down, hide the header. When the user scrolls up, show the header */
var prevScrollpos = window.pageYOffset;
window.onscroll = function() {
var currentScrollPos = window.pageYOffset;
if (prevScrollpos > currentScrollPos) {
document.getElementById("header-scroll-up").style = "top:0px; background-color: #FFFFFF; ";
} else {
document.getElementById("header-scroll-up").style = "top:-122px; background-color: rgba(0, 0, 0, 0); ";
}
prevScrollpos = currentScrollPos;
};