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diff --git a/assets/js/photo-utils.js b/assets/js/photo-utils.js
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+(function() {
+  'use strict';
+
+  // Internal state
+  let currentPhotoIndex = 0;
+  let photosData = [];
+  let isOpen = false;
+  let exifData = {};
+  let options = {
+    swipeEnabled: true,
+    keyboardEnabled: true,
+    extractEXIF: true,
+    onOpen: null,
+    onClose: null,
+  };
+
+  // Lightbox DOM elements (created on first init)
+  let lightboxModal = null;
+  let lightboxImage = null;
+  let lightboxCaption = null;
+  let lightboxSidebar = null;
+
+  /**
+   * Initialize lightbox for a photo collection
+   * @param {string} containerSelector - CSS selector for photo container
+   * @param {Array} photos - Array of photo objects: {src, alt, caption, location}
+   * @param {Object} opts - Options: {swipeEnabled, keyboardEnabled, extractEXIF, onOpen, onClose}
+   * @returns {Object} - {openLightbox, closeLightbox}
+   */
+  function initLightbox(containerSelector, photos, opts = {}) {
+    photosData = photos;
+    options = { ...options, ...opts };
+
+    // Merge options with defaults
+    const container = document.querySelector(containerSelector);
+    if (!container) {
+      console.error('Photo container not found:', containerSelector);
+      return { openLightbox: () => {}, closeLightbox: () => {} };
+    }
+
+    // Attach click listeners to all figures in the container
+    const figures = container.querySelectorAll('figure[data-photo-index]');
+    figures.forEach((figure) => {
+      figure.addEventListener('click', () => {
+        const index = parseInt(figure.dataset.photoIndex, 10);
+        openLightbox(index);
+      });
+    });
+
+    // Return public API
+    return {
+      openLightbox,
+      closeLightbox,
+    };
+  }
+
+  /**
+   * Open lightbox to a specific photo
+   * @param {number} photoIndex - 0-based index into photosData array
+   */
+  function openLightbox(photoIndex) {
+    if (photoIndex < 0 || photoIndex >= photosData.length) {
+      console.warn('Invalid photo index:', photoIndex);
+      return;
+    }
+
+    currentPhotoIndex = photoIndex;
+    isOpen = true;
+
+    // Create lightbox DOM if it doesn't exist
+    if (!lightboxModal) {
+      createLightboxDOM();
+    }
+
+    // Populate lightbox with current photo
+    updateLightboxContent();
+
+    // Show modal
+    lightboxModal.classList.add('visible');
+    document.body.style.overflow = 'hidden';
+
+    // Extract EXIF if enabled
+    if (options.extractEXIF) {
+      extractEXIFForCurrentPhoto();
+    }
+
+    // Attach event listeners
+    attachEventListeners();
+
+    // Callback
+    if (options.onOpen) {
+      options.onOpen(photoIndex);
+    }
+  }
+
+  /**
+   * Close lightbox
+   */
+  function closeLightbox() {
+    if (!isOpen || !lightboxModal) return;
+
+    isOpen = false;
+    lightboxModal.classList.remove('visible');
+    document.body.style.overflow = '';
+
+    // Detach event listeners
+    detachEventListeners();
+
+    // Callback
+    if (options.onClose) {
+      options.onClose();
+    }
+  }
+
+  /**
+   * Create lightbox HTML structure and inject into DOM
+   */
+  function createLightboxDOM() {
+    lightboxModal = document.createElement('div');
+    lightboxModal.className = 'photo-lightbox';
+
+    lightboxModal.innerHTML = `
+      <div class="photo-lightbox-backdrop"></div>
+      <div class="photo-lightbox-container">
+        <button class="photo-lightbox-close" aria-label="Close lightbox">×</button>
+
+        <button class="photo-lightbox-prev" aria-label="Previous photo">←</button>
+
+        <div class="photo-lightbox-content">
+          <img class="photo-lightbox-image" src="" alt="">
+          <div class="photo-lightbox-caption"></div>
+        </div>
+
+        <button class="photo-lightbox-next" aria-label="Next photo">→</button>
+
+        <div class="photo-lightbox-sidebar">
+          <div class="photo-lightbox-sidebar-content"></div>
+        </div>
+      </div>
+    `;
+
+    document.body.appendChild(lightboxModal);
+
+    // Cache element references
+    lightboxImage = lightboxModal.querySelector('.photo-lightbox-image');
+    lightboxCaption = lightboxModal.querySelector('.photo-lightbox-caption');
+    lightboxSidebar = lightboxModal.querySelector('.photo-lightbox-sidebar-content');
+
+    // Attach close button and backdrop click
+    lightboxModal.querySelector('.photo-lightbox-close').addEventListener('click', closeLightbox);
+    lightboxModal.querySelector('.photo-lightbox-backdrop').addEventListener('click', closeLightbox);
+
+    // Attach navigation buttons
+    lightboxModal.querySelector('.photo-lightbox-prev').addEventListener('click', () => navigate(-1));
+    lightboxModal.querySelector('.photo-lightbox-next').addEventListener('click', () => navigate(1));
+  }
+
+  /**
+   * Update lightbox content with current photo
+   */
+  function updateLightboxContent() {
+    const photo = photosData[currentPhotoIndex];
+    if (!photo) return;
+
+    lightboxImage.src = photo.src;
+    lightboxImage.alt = photo.alt || '';
+
+    // Caption
+    if (photo.caption) {
+      lightboxCaption.textContent = photo.caption;
+      lightboxCaption.style.display = 'block';
+    } else {
+      lightboxCaption.style.display = 'none';
+    }
+
+    // Update prev/next button states
+    const prevBtn = lightboxModal.querySelector('.photo-lightbox-prev');
+    const nextBtn = lightboxModal.querySelector('.photo-lightbox-next');
+    prevBtn.disabled = currentPhotoIndex === 0;
+    nextBtn.disabled = currentPhotoIndex === photosData.length - 1;
+  }
+
+  /**
+   * Navigate to previous or next photo
+   * @param {number} direction - -1 for prev, 1 for next
+   */
+  function navigate(direction) {
+    const newIndex = currentPhotoIndex + direction;
+    if (newIndex >= 0 && newIndex < photosData.length) {
+      currentPhotoIndex = newIndex;
+      updateLightboxContent();
+
+      // Reset EXIF data and re-extract if enabled
+      exifData = {};
+      if (options.extractEXIF) {
+        extractEXIFForCurrentPhoto();
+      }
+    }
+  }
+
+  /**
+   * Extract EXIF data from current photo image element
+   */
+  function extractEXIFForCurrentPhoto() {
+    extractEXIF(lightboxImage).then((data) => {
+      exifData = data;
+      updateSidebarContent();
+    });
+  }
+
+  /**
+   * Update sidebar with EXIF and location data
+   */
+  function updateSidebarContent() {
+    const photo = photosData[currentPhotoIndex];
+    let sidebarHTML = '';
+
+    // Always show location if provided
+    if (photo.location) {
+      sidebarHTML += `
+        <div class="photo-metadata-field">
+          <div class="photo-metadata-label">Location</div>
+          <div class="photo-metadata-value">${photo.location}</div>
+        </div>
+      `;
+    }
+
+    // Show EXIF fields if available
+    if (Object.keys(exifData).length > 0) {
+      sidebarHTML += `
+        <div class="photo-metadata-divider"></div>
+        <div class="photo-metadata-label">Camera</div>
+      `;
+
+      if (exifData.camera) {
+        sidebarHTML += `
+          <div class="photo-metadata-value">${exifData.camera}</div>
+        `;
+      }
+      if (exifData.lens) {
+        sidebarHTML += `
+          <div class="photo-metadata-field">
+            <div class="photo-metadata-label">Lens</div>
+            <div class="photo-metadata-value">${exifData.lens}</div>
+          </div>
+        `;
+      }
+      if (exifData.focalLength) {
+        sidebarHTML += `
+          <div class="photo-metadata-field">
+            <div class="photo-metadata-label">Focal Length</div>
+            <div class="photo-metadata-value">${exifData.focalLength}</div>
+          </div>
+        `;
+      }
+      if (exifData.aperture) {
+        sidebarHTML += `
+          <div class="photo-metadata-field">
+            <div class="photo-metadata-label">Aperture</div>
+            <div class="photo-metadata-value">${exifData.aperture}</div>
+          </div>
+        `;
+      }
+      if (exifData.shutterSpeed) {
+        sidebarHTML += `
+          <div class="photo-metadata-field">
+            <div class="photo-metadata-label">Shutter Speed</div>
+            <div class="photo-metadata-value">${exifData.shutterSpeed}</div>
+          </div>
+        `;
+      }
+      if (exifData.iso) {
+        sidebarHTML += `
+          <div class="photo-metadata-field">
+            <div class="photo-metadata-label">ISO</div>
+            <div class="photo-metadata-value">${exifData.iso}</div>
+          </div>
+        `;
+      }
+      if (exifData.dateTaken) {
+        sidebarHTML += `
+          <div class="photo-metadata-field">
+            <div class="photo-metadata-label">Date Taken</div>
+            <div class="photo-metadata-value">${exifData.dateTaken}</div>
+          </div>
+        `;
+      }
+    }
+
+    // Show or hide sidebar based on whether there's content
+    const sidebarContainer = lightboxModal.querySelector('.photo-lightbox-sidebar');
+    if (sidebarHTML) {
+      lightboxSidebar.innerHTML = sidebarHTML;
+      sidebarContainer.classList.add('visible');
+    } else {
+      sidebarContainer.classList.remove('visible');
+    }
+  }
+
+  /**
+   * Extract EXIF data from an image element using exif-js library
+   * @param {HTMLImageElement} imageElement - Image to read EXIF from
+   * @returns {Promise} - Resolves to {camera, lens, iso, aperture, shutterSpeed, focalLength, dateTaken}
+   */
+  function extractEXIF(imageElement) {
+    return new Promise((resolve) => {
+      // If exif-js is not loaded, return empty object
+      if (typeof EXIF === 'undefined') {
+        console.warn('exif-js library not loaded');
+        resolve({});
+        return;
+      }
+
+      EXIF.getData(imageElement, function() {
+        const data = {
+          camera: EXIF.getTag(this, 'Model'),
+          lens: EXIF.getTag(this, 'LensModel'),
+          iso: EXIF.getTag(this, 'ISOSpeedRatings'),
+          aperture: formatAperture(EXIF.getTag(this, 'FNumber')),
+          shutterSpeed: formatShutterSpeed(EXIF.getTag(this, 'ExposureTime')),
+          focalLength: formatFocalLength(EXIF.getTag(this, 'FocalLength')),
+          dateTaken: EXIF.getTag(this, 'DateTime'),
+        };
+
+        // Filter out undefined values
+        Object.keys(data).forEach(key => {
+          if (data[key] === undefined) {
+            delete data[key];
+          }
+        });
+
+        resolve(data);
+      });
+    });
+  }
+
+  /**
+   * Format aperture value (f-number)
+   */
+  function formatAperture(value) {
+    if (!value) return null;
+    if (typeof value === 'object' && value.numerator !== undefined) {
+      return `f/${(value.numerator / value.denominator).toFixed(1)}`;
+    }
+    return `f/${value}`;
+  }
+
+  /**
+   * Format shutter speed (exposure time)
+   */
+  function formatShutterSpeed(value) {
+    if (!value) return null;
+    if (typeof value === 'object' && value.numerator !== undefined) {
+      const speed = value.numerator / value.denominator;
+      if (speed >= 1) {
+        return `${speed.toFixed(1)}s`;
+      }
+      return `1/${Math.round(1 / speed)}`;
+    }
+    return value;
+  }
+
+  /**
+   * Format focal length
+   */
+  function formatFocalLength(value) {
+    if (!value) return null;
+    if (typeof value === 'object' && value.numerator !== undefined) {
+      return `${(value.numerator / value.denominator).toFixed(0)}mm`;
+    }
+    return `${value}mm`;
+  }
+
+  /**
+   * Attach event listeners (swipe, keyboard, etc.)
+   */
+  function attachEventListeners() {
+    if (options.swipeEnabled) {
+      attachSwipeListeners();
+    }
+    if (options.keyboardEnabled) {
+      attachKeyboardListeners();
+    }
+  }
+
+  /**
+   * Detach event listeners to prevent memory leaks
+   */
+  function detachEventListeners() {
+    if (options.swipeEnabled) {
+      detachSwipeListeners();
+    }
+    if (options.keyboardEnabled) {
+      detachKeyboardListeners();
+    }
+  }
+
+  /**
+   * Touch swipe event listeners
+   */
+  let swipeStartX = 0;
+  let swipeStartY = 0;
+
+  function onTouchStart(e) {
+    swipeStartX = e.touches[0].clientX;
+    swipeStartY = e.touches[0].clientY;
+  }
+
+  function onTouchEnd(e) {
+    const swipeEndX = e.changedTouches[0].clientX;
+    const swipeEndY = e.changedTouches[0].clientY;
+    const diffX = swipeEndX - swipeStartX;
+    const diffY = swipeEndY - swipeStartY;
+
+    // Only consider horizontal swipe if delta-x > delta-y
+    if (Math.abs(diffX) > Math.abs(diffY) && Math.abs(diffX) > 50) {
+      if (diffX > 0) {
+        // Swiped right: go to previous
+        navigate(-1);
+      } else {
+        // Swiped left: go to next
+        navigate(1);
+      }
+    }
+  }
+
+  function attachSwipeListeners() {
+    lightboxModal.addEventListener('touchstart', onTouchStart, false);
+    lightboxModal.addEventListener('touchend', onTouchEnd, false);
+  }
+
+  function detachSwipeListeners() {
+    lightboxModal.removeEventListener('touchstart', onTouchStart, false);
+    lightboxModal.removeEventListener('touchend', onTouchEnd, false);
+  }
+
+  /**
+   * Keyboard event listeners
+   */
+  function onKeyDown(e) {
+    if (!isOpen) return;
+
+    switch (e.key) {
+      case 'ArrowLeft':
+        navigate(-1);
+        e.preventDefault();
+        break;
+      case 'ArrowRight':
+        navigate(1);
+        e.preventDefault();
+        break;
+      case 'Escape':
+        closeLightbox();
+        e.preventDefault();
+        break;
+      default:
+        break;
+    }
+  }
+
+  function attachKeyboardListeners() {
+    document.addEventListener('keydown', onKeyDown);
+  }
+
+  function detachKeyboardListeners() {
+    document.removeEventListener('keydown', onKeyDown);
+  }
+
+  // Expose public API
+  window.PhotoUtils = {
+    initLightbox,
+    extractEXIF,
+    openLightbox,
+    closeLightbox,
+  };
+})();