added theme toggle button for dark and light theme

assets/main.js

@@ -51,3 +51,21 @@ function applyFilters() {
         gridEl.innerHTML = '<p>Failed to load projects list.</p>';
     }
 })();
+
+
+        const themeToggle = document.getElementById('themeToggle');
+        const body = document.body;
+
+
+        const currentTheme = localStorage.getItem('theme') || 'light';
+        if (currentTheme === 'dark') {
+            body.classList.add('dark-mode');
+        }
+
+        themeToggle.addEventListener('click', () => {
+            body.classList.toggle('dark-mode');
+
+
+            const theme = body.classList.contains('dark-mode') ? 'dark' : 'light';
+            localStorage.setItem('theme', theme);
+        });

assets/styles.css

@@ -7,6 +7,30 @@
     --accent-2: #93c5fd
 }
 
+
+body:not(.dark-mode) {
+    --bg: #f8f9fa;
+    --card: #ffffff;
+    --text: #1a1a1a;
+    --muted: #6b7280;
+    --bg-gradient-start: #f0f4f8;
+    --bg-gradient-end: #e2e8f0;
+    --border: #e5e7eb;
+    --input-bg: #ffffff;
+}
+
+
+body.dark-mode {
+    --bg: #0f0f12;
+    --card: #17171c;
+    --text: #eef1f8;
+    --muted: #a6adbb;
+    --bg-gradient-start: #0b0b0e;
+    --bg-gradient-end: #121217;
+    --border: #262631;
+    --input-bg: #0e0e13;
+}
+
 * {
     box-sizing: border-box
 }
@@ -19,13 +43,15 @@ body {
 
 body {
     font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, sans-serif;
-    background: linear-gradient(180deg, #0b0b0e, #121217);
-    color: var(--text)
+    background: linear-gradient(180deg, var(--bg-gradient-start, #0b0b0e), var(--bg-gradient-end, #121217));
+    color: var(--text);
+    transition: background 0.3s ease, color 0.3s ease;
 }
 
 .site-header {
     padding: 2rem 1rem;
-    text-align: center
+    text-align: center;
+    position: relative;
 }
 
 .site-header h1 {
@@ -42,16 +68,69 @@ body {
     display: flex;
     gap: .5rem;
     justify-content: center;
-    flex-wrap: wrap
+    flex-wrap: wrap;
+    align-items: center;
 }
 
 .controls input,
 .controls select {
     padding: .5rem .75rem;
     border-radius: .5rem;
-    border: 1px solid #2a2a33;
-    background: #0e0e13;
-    color: var(--text)
+    border: 1px solid var(--border, #2a2a33);
+    background: var(--input-bg, #0e0e13);
+    color: var(--text);
+    transition: background 0.3s ease, border-color 0.3s ease;
+}
+
+
+.theme-toggle {
+    background: var(--card);
+    border: 2px solid var(--border, #262631);
+    border-radius: 50%;
+    width: 50px;
+    height: 50px;
+    cursor: pointer;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    transition: all 0.3s ease;
+    position: fixed;
+    top: 1rem;
+    right: 1rem;
+    z-index: 1000;
+    color: var(--text);
+    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
+}
+
+.theme-toggle:hover {
+    transform: rotate(15deg) scale(1.1);
+    border-color: var(--accent);
+    box-shadow: 0 6px 16px rgba(110, 231, 183, 0.2);
+}
+
+.theme-toggle svg {
+    position: absolute;
+    transition: all 0.3s ease;
+}
+
+.theme-toggle .sun-icon {
+    opacity: 0;
+    transform: rotate(90deg);
+}
+
+.theme-toggle .moon-icon {
+    opacity: 1;
+    transform: rotate(0deg);
+}
+
+body:not(.dark-mode) .theme-toggle .sun-icon {
+    opacity: 1;
+    transform: rotate(0deg);
+}
+
+body:not(.dark-mode) .theme-toggle .moon-icon {
+    opacity: 0;
+    transform: rotate(-90deg);
 }
 
 .project-grid {
@@ -65,10 +144,11 @@ body {
 
 .card {
     background: var(--card);
-    border: 1px solid #262631;
+    border: 1px solid var(--border, #262631);
     border-radius: .75rem;
     padding: 1rem;
-    box-shadow: 0 0 0 1px rgba(255, 255, 255, .02) inset
+    box-shadow: 0 0 0 1px rgba(255, 255, 255, .02) inset;
+    transition: background 0.3s ease, border-color 0.3s ease;
 }
 
 .card h3 {
@@ -110,5 +190,15 @@ body {
     padding: 2rem 1rem;
     text-align: center;
     color: var(--muted);
-    border-top: 1px solid #22222b
+    border-top: 1px solid var(--border, #22222b);
+    transition: border-color 0.3s ease;
+}
+
+.site-footer a {
+    color: var(--accent);
+    text-decoration: none;
+}
+
+.site-footer a:hover {
+    text-decoration: underline;
 }

index.html

@@ -21,6 +21,22 @@ <h1>Vanilla Verse</h1>
                 <option value="visual">Fun UI / Visual</option>
                 <option value="data">Mini Data</option>
             </select>
+            <button id="themeToggle" class="theme-toggle" aria-label="Toggle theme">
+                <svg class="sun-icon" width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2">
+                    <circle cx="12" cy="12" r="5"/>
+                    <line x1="12" y1="1" x2="12" y2="3"/>
+                    <line x1="12" y1="21" x2="12" y2="23"/>
+                    <line x1="4.22" y1="4.22" x2="5.64" y2="5.64"/>
+                    <line x1="18.36" y1="18.36" x2="19.78" y2="19.78"/>
+                    <line x1="1" y1="12" x2="3" y2="12"/>
+                    <line x1="21" y1="12" x2="23" y2="12"/>
+                    <line x1="4.22" y1="19.78" x2="5.64" y2="18.36"/>
+                    <line x1="18.36" y1="5.64" x2="19.78" y2="4.22"/>
+                </svg>
+                <svg class="moon-icon" width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2">
+                    <path d="M21 12.79A9 9 0 1 1 11.21 3 7 7 0 0 0 21 12.79z"/>
+                </svg>
+            </button>
         </div>
     </header>
 
@@ -37,6 +53,7 @@ <h1>Vanilla Verse</h1>
     </footer>
 
     <script src="assets/main.js" type="module"></script>
+
 </body>
 
 </html>