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CSS

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <h1>Image Gallery</h1>

    <div class="gallery" onclick="openLightbox(event)">
        <img src="https://assets.codepen.io/210284/flower-6.jpg"
            alt="Image 1">
        <img src="https://assets.codepen.io/210284/flower-7.jpg"
            alt="Image 2">
        <img src="https://assets.codepen.io/210284/flower-8.jpg"
            alt="Image 3">
        <img src="https://assets.codepen.io/210284/flower-9.jpg"
            alt="Image 4">
    </div>

    <!-- Lightbox container -->
    <div id="lightbox">
        <!-- Close button -->
        <span id="close-btn" onclick="closeLightbox()">&times;</span>

        <!-- Main lightbox image -->
        <img id="lightbox-img" src="" alt="lightbox image">

        <!-- Thumbnails container -->
        <div id="thumbnail-container">
            <!-- Thumbnails will be added dynamically using JavaScript -->
        </div>

        <!-- Previous and Next buttons -->
        <button id="prev-btn" onclick="changeImage(-1)">&lt; Prev</button>
        <button id="next-btn" onclick="changeImage(1)">Next &gt;</button>
    </div>
!

CSS 

              
                @import url('https://fonts.googleapis.com/css2?family=Cormorant+Garamond&family=DM+Mono:wght@400;500&display=swap');


/* Basic styling for the gallery */
        body {
            font-family: 'Cormorant Garamond', sans-serif;
            margin: 0;
            padding: 0;  
            background: #131212;
        }

        h1 {
            text-align: center;
            padding: 40px;
            margin: 0;
            color: beige;
            font-size: 3em;
        }

        .gallery {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            padding: 20px;
        }

        .gallery img {
            margin: 10px;
            cursor: pointer;
            max-width: 300px;
            width: 50%;
            height: 50%;
          border-radius: 10px;
        }

        /* Lightbox styles */
        #lightbox {
            display: none;
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(0, 0, 0, 0.8);
            justify-content: center;
            align-items: center;
            overflow: hidden;
            flex-direction: column;
        }

        #lightbox img {
            max-width: 80%;
            max-height: 60vh;
            box-shadow: 0 0 25px rgba(0, 0, 0, 0.8);
          border-radius: 10px;
        }

        #close-btn {
            position: absolute;
            top: 10px;
            right: 10px;
            font-size: 24px;
            color: #fff;
            cursor: pointer;
            z-index: 2;
        }

        /* Style for navigation buttons */
        #prev-btn,
        #next-btn {
            position: absolute;
            top: 50%;
            transform: translateY(-50%);
            font-size: 20px;
            color: #fff;
            background-color: rgba(0, 0, 0, 0.5);
            border: none;
            padding: 10px;
            cursor: pointer;
            transition: background-color 0.3s;
        }

        #prev-btn {
            left: 10px;
        }

        #next-btn {
            right: 10px;
        }

        #prev-btn:hover,
        #next-btn:hover {
            background-color: rgba(0, 0, 0, 0.8);
        }

        /* Styles for thumbnails */
        .thumbnail-container {
            display: flex;
            flex-direction: row;
            flex-wrap: wrap;
            justify-content: center;
        }
        .thumbnail {
            max-width: 50px;
            width: 100px;
            cursor: pointer;
            margin-top: 40px;
            margin-left: 5px;
            margin-right: 5px;
            border: 2px solid #fff;
            transition: opacity 0.3s;
        }

        .thumbnail:hover,
        .thumbnail.active-thumbnail {
            opacity: 0.7;
        }
!

JS 

              
                let currentIndex = 0;
        const images = document.querySelectorAll('.gallery img');
        const totalImages = images.length;

        // Open the lightbox
        function openLightbox(event) {
            if (event.target.tagName === 'IMG') {
                const clickedIndex = Array.from(images).indexOf(event.target);
                currentIndex = clickedIndex;
                updateLightboxImage();
                document.getElementById('lightbox').style.display = 'flex';
            }
        }

        // Close the lightbox
        function closeLightbox() {
            document.getElementById('lightbox').style.display = 'none';
        }

        // Change the lightbox image based on direction (1 for next, -1 for prev)
        function changeImage(direction) {
            currentIndex += direction;
            if (currentIndex >= totalImages) {
                currentIndex = 0;
            } else if (currentIndex < 0) {
                currentIndex = totalImages - 1;
            }
            updateLightboxImage();
        }

        // Update the lightbox image and thumbnails
        function updateLightboxImage() {
            const lightboxImg = document.getElementById('lightbox-img');
            const thumbnailContainer = document.getElementById('thumbnail-container');

            // Update the main lightbox image
            lightboxImg.src = images[currentIndex].src;

            // Clear existing thumbnails
            thumbnailContainer.innerHTML = '';

            // Add new thumbnails
            images.forEach((image, index) => {
                const thumbnail = document.createElement('img');
                thumbnail.src = image.src;
                thumbnail.alt = `Thumbnail ${index + 1}`;
                thumbnail.classList.add('thumbnail');
                thumbnail.addEventListener('click', () => updateMainImage(index));
                thumbnailContainer.appendChild(thumbnail);
            });

            // Highlight the current thumbnail
            const thumbnails = document.querySelectorAll('.thumbnail');
            thumbnails[currentIndex].classList.add('active-thumbnail');
        }

        // Update the main lightbox image when a thumbnail is clicked
        function updateMainImage(index) {
            currentIndex = index;
            updateLightboxImage();
        }

        // Add initial thumbnails
        updateLightboxImage();


        // To add keyboard navigation (left/right arrow keys)
        document.addEventListener('keydown', function (e) {
            if (document.getElementById('lightbox').style.display === 'flex') {
                if (e.key === 'ArrowLeft') {
                    changeImage(-1);
                } else if (e.key === 'ArrowRight') {
                    changeImage(1);
                }
            }
        });
!
999px

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