diff --git a/Dockerfile b/Dockerfile
index abfff3e..f67bcc1 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,5 @@
 # Use the official Node.js image as a build stage
-FROM node:14 AS build
+FROM node:20-alpine AS build
 
 # Set the working directory
 WORKDIR /app
diff --git a/src/App.js b/src/App.js
index 1b34432..978a4d1 100644
--- a/src/App.js
+++ b/src/App.js
@@ -9,7 +9,7 @@ import Footer from './components/Footer';
 const App = () => {
     return (
         <Router>
-            <div>
+            <>
                 <Navbar />
                 <Routes>
                     <Route path="/" element={<Home />} />
@@ -17,7 +17,7 @@ const App = () => {
                     <Route path="/about" element={<About />} />
                 </Routes>
                 <Footer />
-            </div>
+            </>
         </Router>
     );
 };
diff --git a/src/App.test.js b/src/App.test.js
index 1f03afe..04c2c5f 100644
--- a/src/App.test.js
+++ b/src/App.test.js
@@ -1,8 +1,21 @@
 import { render, screen } from '@testing-library/react';
 import App from './App';
 
-test('renders learn react link', () => {
-  render(<App />);
-  const linkElement = screen.getByText(/learn react/i);
-  expect(linkElement).toBeInTheDocument();
+// masonry-layout requires DOM layout APIs not available in jsdom
+jest.mock('masonry-layout', () => {
+    return jest.fn().mockImplementation(() => ({
+        layout: jest.fn(),
+        destroy: jest.fn(),
+    }));
+});
+
+test('renders site title in navbar', () => {
+    render(<App />);
+    expect(screen.getByText(/Jake Runyan Photography/i)).toBeInTheDocument();
+});
+
+test('renders navigation links', () => {
+    render(<App />);
+    expect(screen.getByRole('link', { name: /contact/i })).toBeInTheDocument();
+    expect(screen.getByRole('link', { name: /about/i })).toBeInTheDocument();
 });
diff --git a/src/components/Footer.js b/src/components/Footer.js
index e5e534f..9718fb2 100644
--- a/src/components/Footer.js
+++ b/src/components/Footer.js
@@ -1,4 +1,5 @@
 import React from 'react';
+import { Link } from 'react-router-dom';
 import './Footer.css';
 
 const Footer = () => {
@@ -12,9 +13,9 @@ const Footer = () => {
                 <p>&copy; {new Date().getFullYear()} Jake Runyan</p>
             </div>
             <div className="footer-links right">
-                <a href="/">Home</a>
-                <a href="/contact">Contact</a>
-                <a href="/about">About</a>
+                <Link to="/">Home</Link>
+                <Link to="/contact">Contact</Link>
+                <Link to="/about">About</Link>
             </div>
         </footer>
     );
diff --git a/src/components/Home.js b/src/components/Home.js
index bf0ce05..02520ad 100644
--- a/src/components/Home.js
+++ b/src/components/Home.js
@@ -1,23 +1,24 @@
-import React, { useEffect, useRef } from 'react';
+import React, { useEffect, useMemo, useRef, useState } from 'react';
 import Masonry from 'masonry-layout';
-import images from '../data/Images'; // Import the image URLs
+import images from '../data/Images';
 import { Helmet } from 'react-helmet';
-import './Home.css'; // Ensure you have your CSS for styling
+import './Home.css';
+import Lightbox from './Lightbox';
 
-// Shuffle function to randomize the array
 const shuffleArray = (array) => {
     for (let i = array.length - 1; i > 0; i--) {
         const j = Math.floor(Math.random() * (i + 1));
-        [array[i], array[j]] = [array[j], array[i]]; // Swap elements
+        [array[i], array[j]] = [array[j], array[i]];
     }
     return array;
 };
 
 const Home = () => {
     const masonryRef = useRef(null);
-    
-    // Shuffle images on component mount
-    const shuffledImages = shuffleArray([...images]); // Create a copy and shuffle
+    const [focusedImage, setFocusedImage] = useState(null);
+
+    // Compute once on mount; avoids a re-shuffle on every render
+    const shuffledImages = useMemo(() => shuffleArray([...images]), []);
 
     useEffect(() => {
         const masonry = new Masonry(masonryRef.current, {
@@ -26,31 +27,27 @@ const Home = () => {
             percentPosition: true,
         });
 
-        // Layout Masonry after images have loaded
-        const imagesLoaded = () => {
-            masonry.layout();
-        };
+        const relayout = () => masonry.layout();
 
-        // Add event listener for image load
         const imgElements = masonryRef.current.querySelectorAll('img');
-        imgElements.forEach(img => {
-            img.addEventListener('load', imagesLoaded);
-        });
+        imgElements.forEach(img => img.addEventListener('load', relayout));
 
         return () => {
-            imgElements.forEach(img => {
-                img.removeEventListener('load', imagesLoaded);
-            });
+            imgElements.forEach(img => img.removeEventListener('load', relayout));
+            masonry.destroy();
         };
     }, []);
 
     return (
-        <div className="gallery" ref={masonryRef}>
-            <Helmet><title>Jake Runyan Photography</title></Helmet>
-            {shuffledImages.map((image, index) => (
-                <img key={index} src={image} alt={`© Jake Runyan ${index + 1}`} className="gallery-photo" />
-            ))}
-        </div>
+        <>
+            <div className="gallery" ref={masonryRef}>
+                <Helmet><title>Jake Runyan Photography</title></Helmet>
+                {shuffledImages.map((image) => (
+                    <img key={image} src={image} alt="© Jake Runyan" className="gallery-photo" style={{ cursor: 'pointer' }} onClick={() => setFocusedImage(image)} />
+                ))}
+            </div>
+            {focusedImage && <Lightbox src={focusedImage} onClose={() => setFocusedImage(null)} />}
+        </>
     );
 };
 
diff --git a/src/components/Lightbox.css b/src/components/Lightbox.css
new file mode 100644
index 0000000..ab6ba1b
--- /dev/null
+++ b/src/components/Lightbox.css
@@ -0,0 +1,50 @@
+@keyframes fadeIn {
+    from { opacity: 0; }
+    to   { opacity: 1; }
+}
+
+@keyframes fadeOut {
+    from { opacity: 1; }
+    to   { opacity: 0; }
+}
+
+.lightbox-overlay {
+    position: fixed;
+    inset: 0;
+    background: rgba(0, 0, 0, 0.88);
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    z-index: 1000;
+    cursor: zoom-out;
+    animation: fadeIn 0.2s ease;
+}
+
+.lightbox-overlay.closing {
+    animation: fadeOut 0.2s ease forwards;
+}
+
+.lightbox-image {
+    max-width: 90vw;
+    max-height: 90vh;
+    object-fit: contain;
+    border-radius: 4px;
+    cursor: zoom-out;
+}
+
+.lightbox-close {
+    position: absolute;
+    top: 1rem;
+    right: 1.25rem;
+    background: none;
+    border: none;
+    color: #fff;
+    font-size: 1.5rem;
+    cursor: pointer;
+    line-height: 1;
+    opacity: 0.7;
+}
+
+.lightbox-close:hover {
+    opacity: 1;
+}
diff --git a/src/components/Lightbox.js b/src/components/Lightbox.js
new file mode 100644
index 0000000..d48b929
--- /dev/null
+++ b/src/components/Lightbox.js
@@ -0,0 +1,42 @@
+import React, { useEffect, useState } from 'react';
+import './Lightbox.css';
+
+const Lightbox = ({ src, onClose }) => {
+    const [closing, setClosing] = useState(false);
+
+    useEffect(() => {
+        if (!closing) return;
+        const t = setTimeout(onClose, 200);
+        return () => clearTimeout(t);
+    }, [closing, onClose]);
+
+    useEffect(() => {
+        const onKey = (e) => { if (e.key === 'Escape') setClosing(true); };
+        document.addEventListener('keydown', onKey);
+        return () => document.removeEventListener('keydown', onKey);
+    }, []);
+
+    useEffect(() => {
+        document.body.style.overflow = 'hidden';
+        return () => { document.body.style.overflow = ''; };
+    }, []);
+
+    return (
+        <div
+            className={`lightbox-overlay${closing ? ' closing' : ''}`}
+            onClick={() => setClosing(true)}
+            role="dialog"
+            aria-modal="true"
+        >
+            <button className="lightbox-close" onClick={() => setClosing(true)} aria-label="Close">✕</button>
+            <img
+                className="lightbox-image"
+                src={src}
+                alt="Full size"
+                onClick={() => setClosing(true)}
+            />
+        </div>
+    );
+};
+
+export default Lightbox;
diff --git a/src/components/Navbar.js b/src/components/Navbar.js
index 8ab1d8c..4067172 100644
--- a/src/components/Navbar.js
+++ b/src/components/Navbar.js
@@ -1,4 +1,4 @@
-import React from 'react';
+import React, { useEffect, useState } from 'react';
 import { Link } from 'react-router-dom';
 import './Navbar.css';
 import logo from './static/navbar-logo.png';
@@ -7,8 +7,17 @@ import github_light from './static/github-light.png';
 import instagram_dark from './static/instagram-dark.png';
 import instagram_light from './static/instagram-light.png';
 
+const darkModeQuery = window.matchMedia('(prefers-color-scheme: dark)');
+
 const Navbar = () => {
-    const isDarkMode = window.matchMedia && window.matchMedia('(prefers-color-scheme: dark)').matches;
+    const [isDarkMode, setIsDarkMode] = useState(darkModeQuery.matches);
+
+    useEffect(() => {
+        const handler = (e) => setIsDarkMode(e.matches);
+        darkModeQuery.addEventListener('change', handler);
+        return () => darkModeQuery.removeEventListener('change', handler);
+    }, []);
+
     const githubIcon = isDarkMode ? github_light : github_dark;
     const instagramIcon = isDarkMode ? instagram_light : instagram_dark;