diff --git a/chat_window.php b/chat_window.php
index 326d01d..eb6e3ba 100644
--- a/chat_window.php
+++ b/chat_window.php
@@ -23,7 +23,8 @@ if (empty($user_id)) {
     <title>Chat WhatsApp - Usuario</title>
     <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css" rel="stylesheet">
     <link href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.0.0/css/all.min.css" rel="stylesheet">
-    <link href="assets/css/styles.css" rel="stylesheet">
+    <?php $asset_v = file_exists(__DIR__ . '/assets/css/styles.css') ? filemtime(__DIR__ . '/assets/css/styles.css') : time(); ?>
+    <link href="assets/css/styles.css?v=<?php echo $asset_v; ?>" rel="stylesheet">
     <style>
         /* Más compacto: reducir la escala base y espacios para interfaces pequeñas */
         body {
diff --git a/conversations.php b/conversations.php
index d7566d7..ddd1f69 100644
--- a/conversations.php
+++ b/conversations.php
@@ -630,7 +630,8 @@
     </div>
 
     <script src="https://cdnjs.cloudflare.com/ajax/libs/bootstrap/5.3.0/js/bootstrap.bundle.min.js"></script>
-    <script src="assets/js/chat-common.js"></script>
+    <?php $asset_v = file_exists(__DIR__ . '/assets/js/chat-common.js') ? filemtime(__DIR__ . '/assets/js/chat-common.js') : time(); ?>
+    <script src="assets/js/chat-common.js?v=<?php echo $asset_v; ?>"></script>
     <script>
         class WhatsAppChat {
             constructor() {