Develop Reference

Proper way to close responsive navbar menu on click of link (in same page)

So, I have a navbar with a (burger icon animation on mobile view) and when I click a link I want the navbar to close & the burger icon cross animation to reverse to normal.
NOTE: This already worked on my previous builds. But since this is a one pager and the link goes out to a section of my page it does not automaticly refresh the page. (Like in my previous projects). I want to do it in vanilla js (so no JQuery).
NOTE2 : This will mainly be a JS problem, but I added the css of the nav just in case.
Thanks in advance
My html code :
<nav id="navbar" class="c-nav">
<div class="logo">
<a href="index.html">
<img class="logo_size" src="./images/Dumotech1.png" alt="Logo van Minter">
</a>
</div>
<ul class="nav-links">
<li><a class="c-underline" href="#about">Over ons</a></li>
<li><a class="c-underline" href="#services">Diensten</a></li>
<li><a class="c-underline" href="#projects">Projecten</a></li>
<li><a class="c-underline" href="#contact">Contact</a></li>
</ul>
<div class="burger">
<div class="line1"></div>
<div class="line2"></div>
<div class="line3"></div>
</div>
</nav>
Css :
.c-nav {
/* overflow-x: hidden; */
text-transform: uppercase;
position: fixed;
z-index: 4;
top: 0;
width: 100%;
height: 5rem;
display: flex;
justify-content: space-around;
align-items: center;
vertical-align: middle;
min-height: 8vh;
background-color: rgb(0, 0, 0);
font-family: 'Raleway', sans-serif;
}
#navbar {
background-color:rgb(0, 0, 0);
position: fixed;
top: 0;
width: 100%;
transition: top 0.5s ease;
}
.logo_size {
max-width: 16rem;
max-height: auto;
}
.nav-links {
display: flex;
justify-content: space-around;
width: 20%;
}
.nav-links li {
list-style: none;
}
.nav-links a {
position: relative;
top: 0.5rem;
color: rgb(255, 255, 255);
font-family: 'Raleway', sans-serif;
text-decoration: none;
letter-spacing: 3px;
font-weight: regular;
font-size: 14px;
padding: 0 1px;
display: inline-block;
}
.c-underline::after {
background: none repeat scroll 0 0 transparent;
bottom: -3px;
content: "";
display: inline-block;
height: 2px;
left: 50%;
position: absolute;
background: rgb(194, 12, 12);
transition: width 0.3s ease 0s, left 0.3s ease 0s;
width: 0;
}
.c-underline:hover::after {
display: inline-block;
width: 100%;
left: 0;
}
.nav-links a:hover {
color: rgb(194, 12, 12);
text-decoration: none;
}
.burger {
display: none;
}
.burger div {
width: 35px;
height: 4px;
background-color: rgb(255, 255, 255);
margin: 8px;
transition: all 0.3s ease;
}
#media screen and (max-width: 1024px) {
.nav-links a {
position: relative;
top: 0;
}
}
#media screen and (max-width: 780px) {
.nav-links {
width: 60%;
}
}
#media screen and (max-width: 1024px) {
.nav-links {
width: 60%;
}
}
#media screen and (max-width: 1920px) {
.nav-links {
width: 40%;
}
}
#media screen and (max-width: 768px) {
body {
overflow-x: hidden;
}
.nav-links {
position: fixed;
right: 0px;
height: 92vh;
top: 8vh;
background-color: rgb(0, 0, 0);
display: flex;
flex-direction: column;
align-items: center;
width: 50%;
transform: translateX(100%);
transition: transform 0.5s ease-in;
}
.nav-links li {
opacity: 0;
}
.burger {
display: block;
cursor: pointer;
}
}
.nav-active {
transform: translateX(0%);
}
#keyframes navLinkFade {
from {
opacity: 0;
transform: translateX(50px);
}
to {
opacity: 1;
transform: translateX(0);
}
}
JS :
function navSlide() {
const burger = document.querySelector(".burger");
const nav = document.querySelector(".nav-links");
const navLinks = document.querySelectorAll(".nav-links li");
burger.addEventListener("click", () => {
//Toggle Nav
nav.classList.toggle("nav-active");
//Animate Links
navLinks.forEach((link, index) => {
if (link.style.animation) {
link.style.animation = ""
} else {
link.style.animation = `navLinkFade 0.5s ease forwards ${index / 7 + 0.3}s`;
}
});
//Burger Animation
burger.classList.toggle("toggle");
});
}

Stop the Image Scrolling when it reached Nav bar CSS and Javascript

I am trying to figure out how to stop the image from moving/scrolling up before it reached the nav bar using javascript and css. but it still can scroll down.
I will really appreciate any help in advance thank you.
I attached the image of the desire output
My code is below
https://codesandbox.io/s/html-css-navbar-forked-06mjm0?file=/src/styles.css
index.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Navigation Bar</title>
<link rel="stylesheet" href="../src/styles.css" />
</head>
<body>
<nav>
<div class="logo">
Brand name
</div>
<div class="menuIcon">
<div class="line"></div>
<div class="line"></div>
<div class="line"></div>
</div>
<ul class="nav-links">
<li class="nav-item active">Home</li>
<li class="nav-item">Services</li>
<li class="nav-item">About</li>
<li class="nav-item">Contact</li>
</ul>
</nav>
<div class="mainSec">
<div id="animatedDiv"></div>
</div>
<script src="src/index.js"></script>
</body>
</html>
index.js
var aDiv = document.getElementById("animatedDiv");
function changeWidth() {
var scrollVal = window.pageYOffset;
//Changing CSS Width
/* This lags if you scroll fast.. aDiv.style.width = (100 - (scrollVal*100/800)) + "%";
I just tried it out, so instead use the code down above, 800 to 1500 doesn't matter, I just increased time of animation
*/
//NOTE this line checks if PERCENT <= 10 then sets width to 10%
50 - (scrollVal * 100) / 1500 <= 10
? (aDiv.style.width = "10%")
: (aDiv.style.width = 50 - (scrollVal * 100) / 1500 + "%");
}
window.addEventListener(
"scroll",
function () {
requestAnimationFrame(changeWidth);
},
false
);
const menuIcon = document.querySelector(".menuIcon");
const menuIcons = document.querySelectorAll(".menuIcon .line");
const navLinks = document.querySelector(".nav-links");
const items = document.querySelectorAll(".nav-links li");
const logo = document.querySelector(".logo");
menuIcon.addEventListener("click", () => {
navLinks.classList.toggle("open");
logo.classList.toggle("close");
items.forEach((item) => {
item.classList.toggle("fade");
});
menuIcons.forEach((Icon) => {
Icon.classList.toggle("open");
});
});
const menu = document.querySelector(".nav-links");
const menuItems = document.querySelectorAll(".nav-links li");
menuItems.forEach((item) => {
item.addEventListener("click", function () {
menu.querySelector(".active").classList.remove("active");
item.classList.add("active");
});
});
style.css
.mainSec {
width: 100%;
display: flex;
justify-content: center;
}
#animatedDiv {
background: url("https://media.tenor.com/images/34b16b199449136a845ea0300ff2cef3/raw")
no-repeat;
min-height: 200vh;
width: 50%;
position: absolute;
margin-top: 20%;
}
#secondPage {
background: url("https://www.downloadclipart.net/large/doraemon-png-free-download.png")
no-repeat;
display: block;
width: 50%;
}
body {
margin: 0;
padding: 0;
box-sizing: border-box;
font-family: sans-serif;
}
nav {
position: fixed;
height: 10vh;
background-color: rgb(12, 77, 151);
display: flex;
align-items: center;
width: 100%;
}
nav .logo a {
color: white;
font-size: 1.5rem;
text-decoration: none;
display: flex;
text-align: center;
margin: 0px 10px;
}
nav .nav-links {
list-style: none;
margin-left: auto;
}
.nav-links li {
display: inline-block;
}
.nav-links .active {
background-color: black;
border: 2px solid black;
border-radius: 10px;
}
nav .nav-links li a {
color: white;
text-decoration: none;
font-size: 1rem;
font-weight: 500;
padding: 0px 10px;
}
#media screen and (max-width: 768px) {
nav {
position: relative;
display: block;
}
.logo {
height: 10vh;
display: flex;
align-items: center;
}
.logo a {
text-align: center;
}
nav .menuIcon {
position: absolute;
cursor: pointer;
top: 30%;
right: 5%;
}
nav .menuIcon .line {
width: 30px;
margin: 5px 0px;
height: 3px;
background-color: white;
position: relative;
}
nav .menuIcon .line:nth-child(1).open {
transform: rotate(45deg);
width: 40px;
height: 5px;
left: 0px;
top: 16px;
transition: all 1s ease;
}
nav .menuIcon .line:nth-child(2).open {
opacity: 0;
}
nav .menuIcon .line:nth-child(3).open {
transform: rotate(-45deg);
width: 40px;
height: 5px;
transition: all 1s ease;
}
nav .nav-links {
margin-top: -10px;
padding: 0px;
height: 90vh;
width: 100%;
background-color: rgb(12, 77, 151);
display: flex;
align-items: center;
flex-direction: column;
clip-path: circle(50px at 90% -10%);
-webkit-clip-path: circle(50px at 90% -10%);
transition: all 1s ease-out;
}
.nav-links li {
margin: 40px 0px;
}
nav .nav-links.open {
clip-path: circle(1000px at 90% -10%);
-webkit-clip-path: circle(1000px at 90% -10%);
}
.nav-links li {
opacity: 0;
}
.nav-links li a {
font-size: 25px;
}
.nav-links li:nth-child(1) {
transition: all 0.5s ease 0.2s;
}
.nav-links li:nth-child(2) {
transition: all 0.5s ease 0.4s;
}
.nav-links li:nth-child(3) {
transition: all 0.5s ease 0.6s;
}
.nav-links li:nth-child(4) {
transition: all 0.5s ease 0.8s;
}
li.fade {
opacity: 1;
}
.logo.close {
visibility: hidden;
}
}

Min Height of #animatedDiv should be set to 87vh instead of 200vh it worked for me. No need to change the JS. See output:
visit
var aDiv = document.getElementById("animatedDiv");
function changeWidth() {
var scrollVal = window.pageYOffset;
//Changing CSS Width
/* This lags if you scroll fast.. aDiv.style.width = (100 - (scrollVal*100/800)) + "%";
I just tried it out, so instead use the code down above, 800 to 1500 doesn't matter, I just increased time of animation
*/
//NOTE this line checks if PERCENT <= 10 then sets width to 10%
50 - (scrollVal * 100) / 1500 <= 10 ?
(aDiv.style.width = "10%") :
(aDiv.style.width = 50 - (scrollVal * 100) / 1500 + "%");
}
window.addEventListener(
"scroll",
function() {
requestAnimationFrame(changeWidth);
},
false
);
const menuIcon = document.querySelector(".menuIcon");
const menuIcons = document.querySelectorAll(".menuIcon .line");
const navLinks = document.querySelector(".nav-links");
const items = document.querySelectorAll(".nav-links li");
const logo = document.querySelector(".logo");
menuIcon.addEventListener("click", () => {
navLinks.classList.toggle("open");
logo.classList.toggle("close");
items.forEach((item) => {
item.classList.toggle("fade");
});
menuIcons.forEach((Icon) => {
Icon.classList.toggle("open");
});
});
const menu = document.querySelector(".nav-links");
const menuItems = document.querySelectorAll(".nav-links li");
menuItems.forEach((item) => {
item.addEventListener("click", function() {
menu.querySelector(".active").classList.remove("active");
item.classList.add("active");
});
});
.mainSec {
width: 100%;
display: flex;
justify-content: center;
}
#animatedDiv {
background: url("https://media.tenor.com/images/34b16b199449136a845ea0300ff2cef3/raw") no-repeat;
display: block;
min-height: 87vh;
width: 50%;
position: absolute;
margin-top: 25%;
z-index: 4;
}
#secondPage {
background: url("https://www.downloadclipart.net/large/doraemon-png-free-download.png") no-repeat;
display: block;
width: 50%;
}
body {
margin: 0;
padding: 0;
box-sizing: border-box;
font-family: sans-serif;
}
nav {
position: fixed;
height: 10vh;
background-color: rgb(12, 77, 151);
display: flex;
align-items: center;
width: 100%;
z-index: 6;
}
nav .logo a {
color: white;
font-size: 1.5rem;
text-decoration: none;
display: flex;
text-align: center;
margin: 0px 10px;
}
nav .nav-links {
list-style: none;
margin-left: auto;
}
.nav-links li {
display: inline-block;
}
.nav-links .active {
background-color: black;
border: 2px solid black;
border-radius: 10px;
}
nav .nav-links li a {
color: white;
text-decoration: none;
font-size: 1rem;
font-weight: 500;
padding: 0px 10px;
}
/*responsive*/
#media screen and (max-width: 768px) {
nav {
position: relative;
display: block;
}
.logo {
height: 10vh;
display: flex;
align-items: center;
}
.logo a {
text-align: center;
}
nav .menuIcon {
position: absolute;
cursor: pointer;
top: 30%;
right: 5%;
}
nav .menuIcon .line {
width: 30px;
margin: 5px 0px;
height: 3px;
background-color: white;
position: relative;
}
nav .menuIcon .line:nth-child(1).open {
transform: rotate(45deg);
width: 40px;
height: 5px;
left: 0px;
top: 16px;
transition: all 1s ease;
}
nav .menuIcon .line:nth-child(2).open {
opacity: 0;
}
nav .menuIcon .line:nth-child(3).open {
transform: rotate(-45deg);
width: 40px;
height: 5px;
transition: all 1s ease;
}
nav .nav-links {
margin-top: -10px;
padding: 0px;
height: 90vh;
width: 100%;
background-color: rgb(12, 77, 151);
display: flex;
align-items: center;
flex-direction: column;
clip-path: circle(50px at 90% -10%);
-webkit-clip-path: circle(50px at 90% -10%);
transition: all 1s ease-out;
}
.nav-links li {
margin: 40px 0px;
}
nav .nav-links.open {
clip-path: circle(1000px at 90% -10%);
-webkit-clip-path: circle(1000px at 90% -10%);
}
.nav-links li {
opacity: 0;
}
.nav-links li a {
font-size: 25px;
}
.nav-links li:nth-child(1) {
transition: all 0.5s ease 0.2s;
}
.nav-links li:nth-child(2) {
transition: all 0.5s ease 0.4s;
}
.nav-links li:nth-child(3) {
transition: all 0.5s ease 0.6s;
}
.nav-links li:nth-child(4) {
transition: all 0.5s ease 0.8s;
}
li.fade {
opacity: 1;
}
.logo.close {
visibility: hidden;
}
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Navigation Bar</title>
<link rel="stylesheet" href="../src/styles.css" />
</head>
<body>
<nav>
<div class="logo">
Brand name
</div>
<div class="menuIcon">
<div class="line"></div>
<div class="line"></div>
<div class="line"></div>
</div>
<ul class="nav-links">
<li class="nav-item active">Home</li>
<li class="nav-item">Services</li>
<li class="nav-item">About</li>
<li class="nav-item">Contact</li>
</ul>
</nav>
<div class="mainSec">
<div id="animatedDiv"></div>
</div>
<script src="src/index.js"></script>
</body>
</html>
It would be best if you changed the CSS for responsiveness.

Navigation menu to Burger Menu

I am trying to make my nav bar menu responsive.
I tried to implement it through several ways but the burger button I am not able to click on it.
I start to think maybe I need to like a jquery link or make sure of the node in my machine .
This is the HTML :
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<link rel="stylesheet" href="style.css">
<title>Showpra</title> </head> <body>
<nav class="main-nav">
<div class="logo">Nav</div>
<ul class="nav-links">
<li>Home</li>
<li>About</li>
<li>Contact</li>
<li>Connect</li>
</ul>
<div class="burger">
<div class="line line1"></div>
<div class="line line2"></div>
<div class="line line3"></div>
</div>
</nav>
<scrip src="script.js"></scrip>
<script src="https://code.jquery.com/jquery-2.1.4.js"></script> </body> </html>
This is the CSS :
#import url('https://fonts.googleapis.com/css2?family=Muli&display=swap');
* {
box-sizing: border-box;
margin: 0;
padding: 0;
}
nav{
display: flex;
justify-content: space-around;
align-items: center;
min-height: 8vh;
background-color: #444;
font-family: 'Muli', sans-serif;
}
.logo
{
color: white;
text-transform: uppercase;
letter-spacing: 5px;
font-size: 20px;
}
.nav-links {
display: flex;
background-color: coral;
justify-content: space-around;
width: 30%
}
.nav-links li {
list-style: none;
}
.nav-links a{
color:cyan;
text-decoration: none;
letter-spacing: 3px;
font-weight: bold;
font-size: 14px;
}
.burger{
display: none;
cursor: pointer;
}
.burger div{
width:25px;
height: 5px;
background-color: white;
margin: 5px;
transition: all 0.3s ease;
}
#media screen and (max-width:768px){
body {
overflow-x: hidden;
}
.nav-links {
position: absolute;
right: 50%;
height: 92vh;
top: 8vh;
background-color: coral;
display: flex;
flex-direction: column;
align-items: center;
width: 50%;
transform: translateX(100%);
transition: transform 0.5s ease-in;
}
.nav-links li{
opacity: 10;
}
.burger {
display: block;
}
}
.nav-active {
transform: translateX(0%);
}
#keyframes navLinkFade {
from {
opacity: 0;
transform: translateX(50px);
}
to {
opacity: 1;
transform: translateX(0px);
}
}
.toggle .line1 {
transform: rotate(-45deg) traslate(-5px, 6px);
}
.toggle .line2 {
opacity: 0;
}
.toggle .line3 {
transform: rotate(45deg) traslate(-5px, 6px);
}
This is the javaScript :
document.addEventListener('DOMContentLoaded', nav)
function nav(){
const burger = document.querySelector('.burger');
const nav = document.querySelector('.main-nav');
burger.addEventListener('click', ()=>{
nav.classList.toggle('show')
})
}
What do you think is the problem

change your js to click once, the menu show , double click and it hides
function nav() {
var x = document.getElementById("burger");
if (x.style.display === "block") {
x.style.display = "none";
} else {
x.style.display = "block";
}
}
you can check a detailed article about responsive hamburger menu in
https://learnjsx.com/category/1/posts/responsive-css-import

The DOMContentLoaded event has probably already fired before the listener is attached. If you don't want to use the onclick attribute, the best practice to check for document.readyState as in the example below. Also, FYI you don't have a show class in your css, so the code below toggles, the class, but the class doesn't actually do anything.
if (document.readyState !== 'loading') {
const burger = document.querySelector('.burger');
const nav = document.querySelector('.main-nav');
burger.addEventListener('click', () => {
nav.classList.toggle('show')
})
}
#import url('https://fonts.googleapis.com/css2?family=Muli&display=swap');
* {
box-sizing: border-box;
margin: 0;
padding: 0;
}
nav {
display: flex;
justify-content: space-around;
align-items: center;
min-height: 8vh;
background-color: #444;
font-family: 'Muli', sans-serif;
}
.logo {
color: white;
text-transform: uppercase;
letter-spacing: 5px;
font-size: 20px;
}
.nav-links {
display: flex;
background-color: coral;
justify-content: space-around;
width: 30%
}
.nav-links li {
list-style: none;
}
.nav-links a {
color: cyan;
text-decoration: none;
letter-spacing: 3px;
font-weight: bold;
font-size: 14px;
}
.burger {
display: none;
cursor: pointer;
}
.burger div {
width: 25px;
height: 5px;
background-color: white;
margin: 5px;
transition: all 0.3s ease;
}
#media screen and (max-width:768px) {
body {
overflow-x: hidden;
}
.nav-links {
position: absolute;
right: 50%;
height: 92vh;
top: 8vh;
background-color: coral;
display: flex;
flex-direction: column;
align-items: center;
width: 50%;
transform: translateX(100%);
transition: transform 0.5s ease-in;
}
.nav-links li {
opacity: 10;
}
.burger {
display: block;
}
}
.nav-active {
transform: translateX(0%);
}
#keyframes navLinkFade {
from {
opacity: 0;
transform: translateX(50px);
}
to {
opacity: 1;
transform: translateX(0px);
}
}
.toggle .line1 {
transform: rotate(-45deg) traslate(-5px, 6px);
}
.toggle .line2 {
opacity: 0;
}
.toggle .line3 {
transform: rotate(45deg) traslate(-5px, 6px);
}
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<link rel="stylesheet" href="style.css">
<title>Showpra</title>
</head>
<body>
<nav class="main-nav">
<div class="logo">Nav</div>
<ul class="nav-links">
<li>Home</li>
<li>About</li>
<li>Contact</li>
<li>Connect</li>
</ul>
<button onclick="toggleNav">Click</button>
<div class="burger">
<div class="line line1"></div>
<div class="line line2"></div>
<div class="line line3"></div>
</div>
</nav>
<scrip src="script.js"></scrip>

#import url('https://fonts.googleapis.com/css2?family=Muli&display=swap');
* {
box-sizing: border-box;
margin: 0;
padding: 0;
}
nav{
display: flex;
justify-content: space-around;
align-items: center;
min-height: 8vh;
background-color: #444;
font-family: 'Muli', sans-serif;
}
.logo
{
color: white;
text-transform: uppercase;
letter-spacing: 5px;
font-size: 20px;
}
.nav-links {
display: flex;
background-color: coral;
justify-content: space-around;
width: 30%
}
.nav-links li {
list-style: none;
}
.nav-links a{
color:cyan;
text-decoration: none;
letter-spacing: 3px;
font-weight: bold;
font-size: 14px;
}
.burger{
display: none;
cursor: pointer;
}
.burger div{
width:25px;
height: 5px;
background-color: white;
margin: 5px;
transition: all 0.3s ease;
}
#media screen and (max-width:768px){
body {
overflow-x: hidden;
}
.nav-links {
position: absolute;
right: 50%;
height: 92vh;
top: 8vh;
background-color: coral;
display: flex;
flex-direction: column;
align-items: center;
width: 50%;
transform: translateX(100%);
transition: transform 0.5s ease-in;
}
.nav-links li{
opacity: 10;
}
.burger {
display: block;
}
}
.nav-active {
transform: translateX(0%);
}
#keyframes navLinkFade {
from {
opacity: 0;
transform: translateX(50px);
}
to {
opacity: 1;
transform: translateX(0px);
}
}
.toggle .line1 {
transform: rotate(-45deg) traslate(-5px, 6px);
}
.toggle .line2 {
opacity: 0;
}
.toggle .line3 {
transform: rotate(45deg) traslate(-5px, 6px);
}
#hamburger {
font-size: 36px;
color: #eee;
}
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<head>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
<link rel="stylesheet" href="style.css">
</head>
<title>Showpra</title>
<body>
<nav class="main-nav">
<div class="logo">Nav</div>
<div id="hamburger" class="fa fa-bars" onclick="nav()"> </div>
<ul class="nav-links">
<li>Home</li>
<li>About</li>
<li>Contact</li>
<li>Connect</li>
</ul>
</nav>
<scrip src="script.js"></scrip>
<script src="https://code.jquery.com/jquery-2.1.4.js"></script> </body> </html>
<script>
function nav(){
$('.nav-links').toggle();
}
</script>

Neat UX Trick Not working. How can I fix it?

Question
The Commented code at the top of the javascript is my attempt to make it so that the relevant chosen button tab (on the nav bar changes color, gets a background etc). But when I uncomment the code at the top, not only does it not work, but the hamburger menu stops working too!
How can I adjust it to make the class work (so that the selected tab is made obvious to the user)?
My Code
//Nav Bar!!
//Button selected gets color change
/*
const selectedNav = document.querySelectorAll('li');
selectedNav.forEach((item)=>{
document.selectedNav.addEventListener('click', navChange)
})
function navChange(event){
ul.forEach((item)=>{
item.classList.remove('add-this-to-selected-section');
})
event.target.classList.add('add-this-to-selected-section');
}
*/
const navSlide = () =>{
const burger = document.querySelector('.burger');
const nav = document.querySelector('.nav-links');
const navLinks = document.querySelectorAll('.nav-links li');
// Toggle Nav
burger.addEventListener('click',()=>{
nav.classList.toggle('nav-active');
//Animate Links
navLinks.forEach((link, index)=>{
if(link.style.animation){
link.style.animation = '';
} else {
link.style.animation = `navLinkFade 0.5s ease forwards ${index / 7 + 0.5}s`
}
})
//Burger Animation
burger.classList.toggle('toggle');
})
}
navSlide();
nav{
display: flex;
justify-content: space-around;
align-items: center;
min-height: 8vh;
font-family: 'Poppins', sans-serif;
background-color: #ffffff;
}
.nav-links{
display: flex;
justify-content: space-around;
width: 50%;
}
.nav-links li{
list-style: none;
}
.nav-links a{
color: #245871;
text-decoration: none;
letter-spacing: 3px;
font-weight: 800;
font-size: 18px;
}
.add-this-to-selected-section{
color: white;
background-color: #245871;
padding: 5px;
border-radius: 5px;
}
.burger div{
width: 25px;
height: 3px;
background-color: #245871;
margin: 5px;
transition: all 0.3s ease;
}
.burger{
display: none;
cursor: pointer;
}
#media screen and (max-width: 1024){
.nav-links{
width: 70%;
cursor: pointer;
font-weight: 1200;
}
}
#media screen and (max-width: 997px){
body{
overflow-x: hidden;
}
nav{
color: white;
}
.head-btn{
color: white;
}
.nav-links{
position: absolute;
right: 0px;
height: 92vh;
top: 8vh;
background-color: #245871;
color: white;
display: flex;
flex-direction: column;
align-items: center;
width: 70%;
transform: translateX(100%);
transition: transform 0.5s ease-in;
}
.nav-links a{
opacity: 1;
color: white;
}
.burger{
display: block;
}
}
.nav-active{
transform: translateX(0%);
color: white;
}
#keyframes navLinkFade{
from{
opacity: 0;
transform: translateX(50px);
} to {
opacity: 1;
transform: translateX(0px);
}
}
<div class="logo">
<h4>xxx</h4>
</div>
<ul class="nav-links">
<li class=".home-btn">xxx</li>
<li class=".exchange-btn">xxx</li>
<li class=".debit-btn">xxx</li>
<li class=".crypto-btn">xxx</li>
<li class=".stock-btn">xxx</li>
</ul>
<div class="burger">
<div class="line1"></div>
<div class="line2"></div>
<div class="line3"></div>
</div>
Your help is greatly appreciated :)

Your background color for that class was the same, and also your javascript for that functionality had some problems. Here's how it should be:
const selectedNav = document.querySelectorAll('li');
const navChange = (index) => {
selectedNav.forEach((item)=>{
item.classList.remove('add-this-to-selected-section');
})
selectedNav[index].classList.add('add-this-to-selected-section');
}
selectedNav.forEach((item, index)=>{
item.addEventListener('click', ()=> navChange(index))
})
const navSlide = () =>{
const burger = document.querySelector('.burger');
const nav = document.querySelector('.nav-links');
const navLinks = document.querySelectorAll('.nav-links li');
// Toggle Nav
burger.addEventListener('click',()=>{
nav.classList.toggle('nav-active');
//Animate Links
navLinks.forEach((link, index)=>{
if(link.style.animation){
link.style.animation = '';
} else {
link.style.animation = `navLinkFade 0.5s ease forwards ${index / 7 + 0.5}s`
}
})
//Burger Animation
burger.classList.toggle('toggle');
})
}
navSlide();
nav{
display: flex;
justify-content: space-around;
align-items: center;
min-height: 8vh;
font-family: 'Poppins', sans-serif;
background-color: #ffffff;
}
.nav-links{
display: flex;
justify-content: space-around;
width: 50%;
}
.nav-links li{
list-style: none;
}
.nav-links a{
color: #245871;
text-decoration: none;
letter-spacing: 3px;
font-weight: 800;
font-size: 18px;
}
.add-this-to-selected-section{
color: white;
background-color: red;
padding: 5px;
border-radius: 5px;
}
.burger div{
width: 25px;
height: 3px;
background-color: #245871;
margin: 5px;
transition: all 0.3s ease;
}
.burger{
display: none;
cursor: pointer;
}
#media screen and (max-width: 1024){
.nav-links{
width: 70%;
cursor: pointer;
font-weight: 1200;
}
}
#media screen and (max-width: 997px){
body{
overflow-x: hidden;
}
nav{
color: white;
}
.head-btn{
color: white;
}
.nav-links{
position: absolute;
right: 0px;
height: 92vh;
top: 8vh;
background-color: #245871;
color: white;
display: flex;
flex-direction: column;
align-items: center;
width: 70%;
transform: translateX(100%);
transition: transform 0.5s ease-in;
}
.nav-links a{
opacity: 1;
color: white;
}
.burger{
display: block;
}
}
.nav-active{
transform: translateX(0%);
color: white;
}
#keyframes navLinkFade{
from{
opacity: 0;
transform: translateX(50px);
} to {
opacity: 1;
transform: translateX(0px);
}
}
<div class="logo">
<h4>xxx</h4>
</div>
<ul class="nav-links">
<li class=".home-btn">xxx</li>
<li class=".exchange-btn">xxx</li>
<li class=".debit-btn">xxx</li>
<li class=".crypto-btn">xxx</li>
<li class=".stock-btn">xxx</li>
</ul>
<div class="burger">
<div class="line1"></div>
<div class="line2"></div>
<div class="line3"></div>
</div>

CSS transition only works one way

Want to add an opacity transition when toggling the menu open/closed. It works when the menu opens, but not when the menu closes. Why is this happening?
// Selectors
let header = document.querySelector('.header')
let hamburgerMenu = document.querySelector('.hamburger-menu')
hamburgerMenu.addEventListener('click', function() {
header.classList.toggle('menu-open');
})
/* Basic reset */
*,
*::before,
*::after {
margin: 0;
padding: 0;
box-sizing: border-box;
}
/* Custom properties */
:root {
--dark-color: #2d2c2c;
--purple-solid: #350a4f;
--purple-transparent: rgba(53, 10, 79, .7);
--purple-transparent-alt: rgba(53, 10, 79, .5);
--purple-light: #8f50fb;
--yellow-solid: #fa9e2c;
--gradient-color: linear-gradient(to right, var(--yellow-solid), var(--purple-light));
--gradient-color-alt: linear-gradient(to right, var(--purple-light), var(--yellow-solid));
}
/* Global styles */
html {
font-size: 10px;
}
body {
font-family: 'Open Sans', sans-serif;
font-size: 1.6rem;
color: var(--dark-color);
}
a {
text-decoration: none;
color: inherit;
}
ul {
list-style: none;
}
section {
padding: 5rem 0;
}
/* Reusable styles */
.container {
width: 100%;
max-width: 120rem;
padding: 0 1.5rem;
margin: 0 auto;
}
/*
.header
.container
.nav
.logo
img
.hamburger-menu
i
.nav-list
.nav-item
.nav-link
*/
/* Header styles */
.header {
background-color: var(--purple-transparent);
width: 100%;
height: 6rem;
display: flex;
align-items: center;
position: fixed;
top: 0;
left: 0;
z-index: 1000;
}
/* Header styles - nav */
.nav {
display: flex;
align-items: center;
justify-content: space-between;
}
.hamburger-menu {
font-size: 2.6rem;
color: #fff;
cursor: pointer;
position: relative;
z-index: 1500;
}
.hamburger-menu .fa-times {
display: none;
}
.menu-open .nav-list {
opacity: 100%;
transform: scale(1);
transition: opacity .5s;
}
.menu-open .hamburger-menu .fa-times {
display: block;
}
.menu-open .hamburger-menu .fa-bars {
display: none;
}
.nav-list {
background-color: var(--purple-solid);
position: fixed;
top: 0;
left: 0;
width: 100%;
height: 100vh;
display: flex;
flex-direction: column;
align-items: center;
justify-content: center;
z-index: 1400;
opacity: 0;
transform: scale(0);
transition: opacity .5s;
}
/*
.header
.container
.nav
.logo
img
.hamburger-menu
i
.nav-list
.nav-item
.nav-link
*/
.nav-item:not(last-child) {
margin-bottom: 4rem;
}
.nav-link {
display: block; /* allows us to use margin & paddings - by default they're inline elements and so no margin / padding */
color: #fff;
font-size: 3rem;
text-transform: uppercase;
letter-spacing: 2px;
cursor: pointer;
padding: 1rem;
}
<header class="header">
<div class="container">
<nav class="nav">
<div class="hamburger-menu">
<i class="fas fa-bars"></i>
<i class="fas fa-times"></i>
</div>
<ul class="nav-list">
<li class="nav-item">
Home
</li>
<li class="nav-item">
About
</li>
<li class="nav-item">
Offers
</li>
<li class="nav-item">
News
</li>
<li class="nav-item">
Contact
</li>
</ul>
</nav>
</div>
</header>

Probably not the answer you wanted, but I hope it helps.
By removing the transform: scale(1); (and transform: scale(0);) the transition works smooth both ways. Was that transformation really needed?
Try with:
.menu-open .nav-list {
opacity: 100%;
transition: all .5s ease-in-out;
visibility: visible;
}
.nav-list {
background-color: var(--purple-solid);
position: fixed;
top: 0;
left: 0;
width: 100%;
height: 100vh;
display: flex;
flex-direction: column;
align-items: center;
justify-content: center;
z-index: 1400;
opacity: 0;
transition: all .5s ease-in-out;
visibility: hidden;
}