Sticky Navbars Using Vanilla JS - top and bottom navs

Vanilla JS (minimalist ES5) Sticky Navbars on top and bottom. Based off a blog post: https://codecary.com/sticky-navigation-bar-on-scroll-using-vanilla-javascript/

by andioak

HTML

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>Sticky Navigation</title>
    <!-----Custom CSS File--->
    <link rel="stylesheet" href="style.css">
</head>
<body>

  <!---Header Section--->
  <div class="banner">
    <nav class="header">
      <a href="#" class="logo">Bindas</a>
      <ul>
        <li><a href="#">home</a></li>
        <li><a href="#">about</a></li>
        <li><a href="#">service</a></li>
        <li><a href="#">portfolio</a></li>
        <li><a href="#">team</a></li>
        <li><a href="#">contact</a></li>
      </ul>
    </nav>
    <div class="banner-text">
      <h1>Sticky Navbar on Scroll Using Javascript</h1>
      <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Aperiam praesentium fuga delectus, magnam hic a minima enim repellendus omnis minus voluptatibus, vitae quo autem ut architecto quaerat recusandae alias voluptatem.Lorem ipsum dolor sit amet consectetur adipisicing elit. Aperiam praesentium fuga delectus, magnam hic a minima enim repellendus omnis minus voluptatibus, vitae quo autem ut architecto quaerat recusandae alias voluptatem.Lorem ipsum dolor sit amet consectetur adipisicing elit. Aperiam praesentium fuga delectus, magnam hic a minima enim repellendus omnis minus voluptatibus, vitae quo autem ut architecto quaerat recusandae alias voluptatem.<br><br>

        Lorem ipsum dolor sit amet consectetur adipisicing elit. Aperiam praesentium fuga delectus, magnam hic a minima enim repellendus omnis minus voluptatibus, vitae quo autem ut architecto quaerat recusandae alias voluptatem.
      </p><br><br>
	  
	  <h2>Sticky Navbar on Scroll Using Javascript, now also on the bottom, a mobile sticky footer.</h2>
	  <p>This was first seen on <a href="https://codecary.com/sticky-navigation-bar-on-scroll-using-vanilla-javascript/">https://codecary.com/sticky-navigation-bar-on-scroll-using-vanilla-javascript/</a> and I fiddled...

CSS

@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@300;500;600;700;800&display=swap');

*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Poppins', sans-serif;
}
html{
  scroll-behavior: smooth;
  background-color: #fff;
}

body {
  padding-bottom: 80px;
}

a {
  text-decoration: none;
}

h1, h2, h3 { margin-bottom: 1em; }

.banner{
  width: 100%;
  min-height: 700px;
  background-image: url(img/banner.jpg);
  background-size: cover;
  background-position: center;
  position: relative;
  z-index: 1;
}
.banner:before{
  content: "";
  position: absolute;
  background: rgba(7,1,90,0.6);
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  z-index: -1;
}
nav{
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 100px;
  border-bottom: 1px solid rgba(235,235,235,0.5);
}
nav .logo{
  font-size: 32px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: #fff;
}
nav ul li{
  list-style: none;
  display: inline-block;
  padding: 8px 12px;
}
nav ul li a{
  color: #fff;
  text-transform: uppercase;
  font-weight: 500;
  transition: .3s;
}
nav ul li a:hover{
  color: #7564e5;
}

.header.sticky{
  background: #fff;
  position: fixed;
  width: 100%;
  padding: 10px 80px;
  top: 0;
  transition: all 0.4s ease;
  box-shadow: 0px 1px 15px rgb(0 0 0 / 10%);
  z-index: 999;
}
.header.sticky .logo{
  color: #7564e5;
}
.header.sticky ul li a{
  color: #333;
}
.header.sticky ul li a:hover {
  color: #7564e5;
}




/* footer sticky as well, with position: fixed  */

.footer_dark { background-color: #000; color: #CCC; }

.footer {
  position: fixed;
  width: 100%;
  text-align: center;
  bottom: 0; left: 0;
  transition: all 0.4s ease;
  z-index: 999;
}

.footer nav {
	padding: 25px 5%;
	border-bottom: none;
	text-align: center;
}

.footer nav ul {
	text-align: center;
}

.footer.sticky ul li a {
  color: #333;
}

.footer.sticky ul li a:hover{
  color: #7564e5;
}



.banner-text{
 ...

JavaScript

/* scroll menu  */
window.addEventListener('scroll', function(){
  var header = document.querySelector('.header');
  header.classList.toggle("sticky", window.scrollY > 0);
})