diff --git a/.gitignore b/.gitignore
index 5dc86f1..d62c839 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,6 +2,8 @@
 dist/
 # generated types
 .astro/
+# generated original images for lightbox
+public/originals/
 
 # dependencies
 node_modules/
diff --git a/astro.config.mjs b/astro.config.mjs
index 67e3eef..3bc5ee0 100644
--- a/astro.config.mjs
+++ b/astro.config.mjs
@@ -2,6 +2,7 @@
 import { defineConfig } from 'astro/config';
 import tailwindcss from '@tailwindcss/vite';
 import sitemap from '@astrojs/sitemap';
+
 // https://astro.build/config
 export default defineConfig({
   site: 'https://www.codingwithcalvin.net',
diff --git a/package.json b/package.json
index f1c8a5e..cf29a18 100644
--- a/package.json
+++ b/package.json
@@ -3,12 +3,13 @@
   "type": "module",
   "version": "0.0.1",
   "scripts": {
-    "dev": "astro dev",
-    "build": "astro build",
+    "dev": "node scripts/copy-originals.js && astro dev",
+    "build": "node scripts/copy-originals.js && astro build",
     "preview": "astro preview",
     "astro": "astro",
     "new": "node scripts/new-post.js",
     "cover": "node scripts/generate-cover.js",
+    "copy-originals": "node scripts/copy-originals.js",
     "compress": "node scripts/compress-images.js"
   },
   "dependencies": {
diff --git a/scripts/copy-originals.js b/scripts/copy-originals.js
new file mode 100644
index 0000000..eb41a0c
--- /dev/null
+++ b/scripts/copy-originals.js
@@ -0,0 +1,55 @@
+import { readdir, copyFile, mkdir } from "fs/promises";
+import { existsSync } from "fs";
+import { join, extname } from "path";
+import { fileURLToPath } from "url";
+import { dirname } from "path";
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+const blogDir = join(__dirname, "..", "src", "content", "blog");
+const outputDir = join(__dirname, "..", "public", "originals");
+
+const IMAGE_EXTENSIONS = [".png", ".jpg", ".jpeg", ".gif", ".webp"];
+
+async function copyOriginals() {
+  console.log("Copying original images to public/originals...\n");
+
+  let copiedCount = 0;
+
+  // Get all years
+  const years = await readdir(blogDir, { withFileTypes: true });
+
+  for (const year of years.filter((d) => d.isDirectory())) {
+    const yearDir = join(blogDir, year.name);
+    const slugs = await readdir(yearDir, { withFileTypes: true });
+
+    for (const slug of slugs.filter((d) => d.isDirectory())) {
+      const postDir = join(yearDir, slug.name);
+      const files = await readdir(postDir, { withFileTypes: true });
+
+      const images = files.filter(
+        (f) =>
+          f.isFile() && IMAGE_EXTENSIONS.includes(extname(f.name).toLowerCase())
+      );
+
+      if (images.length === 0) continue;
+
+      // Create output directory for this post
+      const postOutputDir = join(outputDir, year.name, slug.name);
+      if (!existsSync(postOutputDir)) {
+        await mkdir(postOutputDir, { recursive: true });
+      }
+
+      // Copy each image
+      for (const image of images) {
+        const src = join(postDir, image.name);
+        const dest = join(postOutputDir, image.name);
+        await copyFile(src, dest);
+        copiedCount++;
+      }
+    }
+  }
+
+  console.log(`Copied ${copiedCount} original images.\n`);
+}
+
+copyOriginals().catch(console.error);
diff --git a/src/layouts/PostLayout.astro b/src/layouts/PostLayout.astro
index d54f2cd..5ceb1ba 100644
--- a/src/layouts/PostLayout.astro
+++ b/src/layouts/PostLayout.astro
@@ -86,6 +86,88 @@ const ogImageUrl = image?.src;
 
           pre.replaceWith(div);
         });
+
+        // Create lightbox overlay
+        const lightbox = document.createElement('div');
+        lightbox.className = 'lightbox-overlay';
+        lightbox.innerHTML = `
+          <div class="lightbox-header">
+            <span class="lightbox-title">Full-size image</span>
+            <span class="lightbox-hint">Click outside or press Esc to close</span>
+          </div>
+          <div class="lightbox-container">
+            <img src="" alt="" />
+          </div>
+          <button class="lightbox-close" aria-label="Close">&times;</button>
+          <div class="lightbox-footer">
+            <span>Click anywhere outside the image to close</span>
+          </div>
+        `;
+        document.body.appendChild(lightbox);
+
+        const lightboxImg = lightbox.querySelector('.lightbox-container img');
+        const closeBtn = lightbox.querySelector('.lightbox-close');
+        const container = lightbox.querySelector('.lightbox-container');
+
+        // Close lightbox on overlay click (but not container), close button, or Escape key
+        lightbox.addEventListener('click', (e) => {
+          if (e.target === lightbox || e.target === closeBtn || e.target.closest('.lightbox-header') || e.target.closest('.lightbox-footer')) {
+            lightbox.classList.remove('active');
+          }
+        });
+        // Prevent closing when clicking the container
+        container.addEventListener('click', (e) => e.stopPropagation());
+        document.addEventListener('keydown', (e) => {
+          if (e.key === 'Escape') lightbox.classList.remove('active');
+        });
+
+        // Get the current post slug from the URL
+        const pathParts = window.location.pathname.split('/').filter(Boolean);
+        const slug = pathParts[pathParts.length - 1] || pathParts[pathParts.length - 2];
+
+        // Make prose images clickable to open lightbox with original
+        document.querySelectorAll('.prose img').forEach((img) => {
+          // Skip if already wrapped in a link
+          if (img.parentElement?.tagName === 'A') return;
+
+          img.addEventListener('click', () => {
+            // Extract the filename from the optimized src
+            const src = img.getAttribute('src') || '';
+            const alt = img.getAttribute('alt') || '';
+
+            // Try to find the original image
+            // The optimized path is like /_astro/filename.hash.webp
+            // We need to map it back to /originals/YEAR/SLUG/filename.png
+            const match = src.match(/\/_astro\/([^.]+)\./);
+            if (match) {
+              const baseName = match[1];
+              // Try common extensions
+              const year = window.location.pathname.match(/\/(\d{4})\//)?.[1];
+              if (year && slug) {
+                // Try to load the original
+                const originalPath = `/originals/${year}/${slug}/${baseName}.png`;
+                lightboxImg.src = originalPath;
+                lightboxImg.alt = alt;
+                lightbox.classList.add('active');
+
+                // Fallback to optimized if original fails
+                lightboxImg.onerror = () => {
+                  // Try jpg
+                  lightboxImg.src = `/originals/${year}/${slug}/${baseName}.jpg`;
+                  lightboxImg.onerror = () => {
+                    // Fall back to optimized version
+                    lightboxImg.src = src;
+                  };
+                };
+              }
+            } else {
+              // Use the src as-is if we can't parse it
+              lightboxImg.src = src;
+              lightboxImg.alt = alt;
+              lightbox.classList.add('active');
+            }
+          });
+        });
       </script>
 
       <blockquote class="mt-12 border-l-4 border-primary bg-background-2 rounded-r-lg p-6 text-center">
diff --git a/src/styles/global.css b/src/styles/global.css
index 8cbbde8..7267f77 100644
--- a/src/styles/global.css
+++ b/src/styles/global.css
@@ -95,6 +95,130 @@ code {
   margin-bottom: 1.5em;
 }
 
+/* Clickable images */
+.prose img {
+  cursor: zoom-in;
+  transition: transform 0.2s ease, box-shadow 0.2s ease;
+}
+
+.prose img:hover {
+  transform: scale(1.01);
+  box-shadow: 0 4px 20px rgba(51, 145, 203, 0.3);
+}
+
+/* Lightbox */
+.lightbox-overlay {
+  position: fixed;
+  inset: 0;
+  background: rgba(0, 0, 0, 0.9);
+  z-index: 9999;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  cursor: zoom-out;
+  opacity: 0;
+  visibility: hidden;
+  transition: opacity 0.3s ease, visibility 0.3s ease;
+  backdrop-filter: blur(8px);
+}
+
+.lightbox-overlay.active {
+  opacity: 1;
+  visibility: visible;
+}
+
+.lightbox-header {
+  position: absolute;
+  top: 0;
+  left: 0;
+  right: 0;
+  height: 4rem;
+  background: linear-gradient(to bottom, rgba(0, 0, 0, 0.8), transparent);
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  padding: 0 4.5rem 0 1.5rem;
+}
+
+.lightbox-title {
+  color: rgba(255, 255, 255, 0.9);
+  font-size: 0.875rem;
+  font-weight: 500;
+}
+
+.lightbox-hint {
+  color: rgba(255, 255, 255, 0.5);
+  font-size: 0.75rem;
+  margin-top: 0.5rem;
+}
+
+.lightbox-container {
+  position: relative;
+  padding: 1rem;
+  background: var(--color-background-2);
+  border-radius: 0.75rem;
+  border: 1px solid var(--color-primary);
+  box-shadow:
+    0 0 0 1px rgba(51, 145, 203, 0.3),
+    0 8px 32px rgba(0, 0, 0, 0.5),
+    0 0 80px rgba(51, 145, 203, 0.15);
+  max-width: 95vw;
+  max-height: 85vh;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+}
+
+.lightbox-container img {
+  max-width: 100%;
+  max-height: calc(85vh - 2rem);
+  object-fit: contain;
+  border-radius: 0.5rem;
+}
+
+.lightbox-close {
+  position: absolute;
+  top: 1rem;
+  right: 1rem;
+  background: var(--color-primary);
+  border: none;
+  color: white;
+  font-size: 1.5rem;
+  width: 2.5rem;
+  height: 2.5rem;
+  border-radius: 50%;
+  cursor: pointer;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  transition: background 0.2s ease, transform 0.2s ease;
+  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
+}
+
+.lightbox-close:hover {
+  background: var(--color-primary-hover);
+  transform: scale(1.1);
+}
+
+.lightbox-footer {
+  position: absolute;
+  bottom: 0;
+  left: 0;
+  right: 0;
+  height: 3rem;
+  background: linear-gradient(to top, rgba(0, 0, 0, 0.8), transparent);
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  padding: 0 1.5rem;
+}
+
+.lightbox-footer span {
+  color: rgba(255, 255, 255, 0.6);
+  font-size: 0.75rem;
+}
+
 .prose h2 {
   margin-top: 2em;
   margin-bottom: 1em;