const sections = document.querySelectorAll("section[id]");
const navLinks = document.querySelectorAll(".case-nav a");
let lastScroll = window.pageYOffset;
window.addEventListener("scroll", () => {
const currentScroll = window.pageYOffset;
const nav = document.querySelector(".case-nav");
// Hide on scroll down
if(currentScroll > lastScroll + 8){
nav.classList.add("hide");
}
// Show on scroll up
if(currentScroll < lastScroll - 8){
nav.classList.remove("hide");
}
lastScroll = currentScroll;
// Active section
let current = "";
sections.forEach(section=>{
const top = section.offsetTop - 180;
if(currentScroll >= top){
current = section.getAttribute("id");
}
});
navLinks.forEach(link=>{
link.classList.remove("active");
if(link.getAttribute("href")==="#"+current){
link.classList.add("active");
}
});
// Progress
const docHeight =
document.documentElement.scrollHeight -
window.innerHeight;
const progress =
(currentScroll/docHeight)*100;
document.querySelector(".progress")
.style.setProperty("--progress",progress+"%");
});