feat: add footer

index.html

···
                     </div>
                 </main>
             </div>
+            <footer>
+                <p>
+                    <a
+                        href="https://tangled.org/julien.rbrt.fr/knotview"
+                        target="_blank"
+                        rel="noopener noreferrer"
+                    >
+                        Fork me on Tangled.
+                    </a>
+                </p>
+            </footer>
         </div>
     </body>
 </html>

styles.css

···
     border: 0;
 }
 
+footer {
+    padding: 20px;
+    text-align: center;
+    border-top: 1px solid var(--border-primary);
+    margin-top: 40px;
+}
+
+footer p {
+    margin: 0;
+    color: var(--text-secondary);
+    font-size: 0.9rem;
+}
+
+footer a {
+    color: var(--accent-primary);
+    text-decoration: none;
+    font-weight: 500;
+}
+
+footer a:hover {
+    text-decoration: underline;
+    color: var(--accent-hover);
+}
+
 @media (max-width: 768px) {
     .main-content {
         flex-direction: column;