gwp/js/scripts.js

var SearchCollapse = document.getElementById('SearchCollapse')
var bsCollapse = new bootstrap.Collapse(SearchCollapse, {
  toggle: false
})

document.addEventListener("DOMContentLoaded", function(){
  gwp_autohide = document.querySelector('.autohide');
  navbar_height = document.querySelector('.navbar').offsetHeight;
  document.body.style.paddingTop = navbar_height + 'px';
  if(gwp_autohide){
    var last_scroll_top = 0;
    window.addEventListener('scroll', function() {
    var y = window.scrollY;
    let scroll_top = window.scrollY;
    if(scroll_top < last_scroll_top || y < navbar_height) {
      gwp_autohide.classList.remove('scrolled-down');
      gwp_autohide.classList.add('scrolled-up');
    }
    else {
      gwp_autohide.classList.remove('scrolled-up');
      gwp_autohide.classList.add('scrolled-down');
    }
    last_scroll_top = scroll_top;
    }); 
  }
});