feat: scroll top button

public/app.js

@@ -8,6 +8,7 @@ const searchInput = document.getElementById('searchInput');
 const linksContainer = document.getElementById('linksContainer');
 const toastContainer = document.getElementById('toastContainer');
 const archiveToggle = document.getElementById('archiveToggle');
+const scrollToTopBtn = document.getElementById('scrollToTopBtn');
 
 // State
 let allLinks = [];
@@ -18,6 +19,7 @@ let showArchived = false;
 document.addEventListener('DOMContentLoaded', () => {
     loadLinks();
     setupEventListeners();
+    setupScrollToTop();
 });
 
 // Event listeners
@@ -27,6 +29,26 @@ function setupEventListeners() {
     archiveToggle.addEventListener('click', handleToggleArchive);
 }
 
+// Setup scroll to top button
+function setupScrollToTop() {
+    // Show/hide button based on scroll position
+    window.addEventListener('scroll', () => {
+        if (window.pageYOffset > 300) {
+            scrollToTopBtn.classList.add('show');
+        } else {
+            scrollToTopBtn.classList.remove('show');
+        }
+    });
+
+    // Scroll to top when button is clicked
+    scrollToTopBtn.addEventListener('click', () => {
+        window.scrollTo({
+            top: 0,
+            behavior: 'smooth'
+        });
+    });
+}
+
 // Load all links
 async function loadLinks() {
     try {