diff --git a/static/js/auth.js b/static/js/auth.js
index b7f711cd..81bec312 100644
--- a/static/js/auth.js
+++ b/static/js/auth.js
@@ -58,7 +58,7 @@ class AuthManager {
 
     async login(username, password) {
         const errorElement = document.getElementById('login-error');
-        const loginBtn = document.querySelector('.login-btn');
+        const loginBtn = document.getElementById('login-btn');
         
         try {
             loginBtn.innerHTML = '<i class="fas fa-spinner fa-spin"></i> Authenticating...';