diff --git a/static/js/app.js b/static/js/app.js
new file mode 100644
index 0000000..66cf1d2
--- /dev/null
+++ b/static/js/app.js
@@ -0,0 +1,61 @@
+/* =====================================================
+   Raccoon Timekeeper - JavaScript Utilities
+   ===================================================== */
+
+// Format minutes to H:MM
+function formatMinutes(totalMinutes) {
+    if (!totalMinutes) return '0:00';
+    const hours = Math.floor(totalMinutes / 60);
+    const mins = totalMinutes % 60;
+    return `${hours}:${mins.toString().padStart(2, '0')}`;
+}
+
+// Show toast notification
+function showToast(message, type = 'success') {
+    const container = document.getElementById('toastContainer');
+    if (!container) return;
+    
+    const toast = document.createElement('div');
+    toast.className = `toast toast-${type}`;
+    toast.textContent = message;
+    container.appendChild(toast);
+    
+    setTimeout(() => {
+        toast.style.opacity = '0';
+        setTimeout(() => toast.remove(), 300);
+    }, 3000);
+}
+
+// Toggle user dropdown menu
+function toggleUserMenu() {
+    const dropdown = document.getElementById('userDropdown');
+    if (dropdown) {
+        dropdown.classList.toggle('active');
+    }
+}
+
+// Close dropdown when clicking outside
+document.addEventListener('click', function(e) {
+    const userMenu = document.querySelector('.user-menu');
+    const dropdown = document.getElementById('userDropdown');
+    
+    if (userMenu && dropdown && !userMenu.contains(e.target)) {
+        dropdown.classList.remove('active');
+    }
+});
+
+// Close modals with Escape key
+document.addEventListener('keydown', function(e) {
+    if (e.key === 'Escape') {
+        document.querySelectorAll('.modal.active').forEach(modal => {
+            modal.classList.remove('active');
+        });
+    }
+});
+
+// Close modal when clicking backdrop
+document.addEventListener('click', function(e) {
+    if (e.target.classList.contains('modal')) {
+        e.target.classList.remove('active');
+    }
+});