<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">

    <title>Image gallery</title>

    <link rel="stylesheet" href="style.css">
    
  </head>

  <body>
    <h1>Image gallery example</h1>

    <div class="full-img">
      <img class="displayed-img" src="images/pic1.jpg">
      <div class="overlay"></div>
      <button class="dark">Darken</button>
    </div>

    <div class="thumb-bar">


    </div>
    <script src="main.js"></script>
  </body>
</html>
h1 {
  font-family: helvetica, arial, sans-serif;
  text-align: center;
}

body {
  width: 640px;
  margin: 0 auto;
}

.full-img {
  position: relative;
  display: block;
  width: 640px;
  height: 480px;
}

.overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 640px;
  height: 480px;
  background-color: rgba(0,0,0,0);
}

button {
  border: 0;
  background: rgba(150,150,150,0.6);
  text-shadow: 1px 1px 1px white;
  border: 1px solid #999;
  position: absolute;
  cursor: pointer;
  top: 2px;
  left: 2px;
}

.thumb-bar img {
  display: block;
  width: 20%;
  float: left;
  cursor: pointer;
}
const displayedImage = document.querySelector('.displayed-img');
const thumbBar = document.querySelector('.thumb-bar');

const btn = document.querySelector('button');
const overlay = document.querySelector('.overlay');

/* Declaring the array of image filenames */

const pics = ["pic1.jpg", "pic2.jpg", "pic3.jpg", "pic4.jpg", "pic5.jpg"]

/* Looping through images */

for (let i = 0; i < pics.length; i++) {
    const newImage = document.createElement('img');
    newImage.setAttribute('src', "images/" + pics[i]);
    newImage.addEventListener('click', function () {
        displayedImage.src = newImage.src;
    })
    thumbBar.appendChild(newImage);
};

/* Wiring up the Darken/Lighten button */

btn.addEventListener('click', function() {
    if (btn.classList.contains('dark')) {
        this.setAttribute('class', 'light');
        btn.textContent = "Lighten";
        overlay.style.backgroundColor = "rgba(0,0,0,0.5)";
    } else {
        btn.setAttribute('class', 'dark');
        btn.textContent = "Darken";
        overlay.style.backgroundColor = "rgba(0,0,0,0)";
    }
})
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