diff --git a/index.php b/index.php
index e717e65..450fa80 100644
--- a/index.php
+++ b/index.php
@@ -82,27 +82,29 @@ $servers = get_user_servers($user_id);
 
         let activeServerId = null;
         let activeChannelId = null;
+        let messagePollingInterval = null;
 
         servers.forEach(server => {
             server.addEventListener('click', function() {
                 const serverId = this.dataset.serverId;
                 if (serverId === activeServerId) return;
 
-                // Update active state for server icons
                 servers.forEach(s => s.classList.remove('active'));
                 this.classList.add('active');
 
                 activeServerId = serverId;
-                activeChannelId = null; // Reset channel selection
+                activeChannelId = null;
+                if (messagePollingInterval) {
+                    clearInterval(messagePollingInterval);
+                    messagePollingInterval = null;
+                }
 
-                // Clear UI
                 serverNameEl.textContent = 'Chargement...';
                 channelsListEl.innerHTML = '';
                 messagesListEl.innerHTML = '<div style="text-align: center; color: var(--text-muted); margin-top: 20px;">Sélectionnez un canal.</div>';
                 channelNameEl.textContent = '';
                 messageForm.style.display = 'none';
 
-                // Fetch server data (channels)
                 fetch(`get_channels.php?server_id=${serverId}`)
                     .then(response => response.json())
                     .then(data => {
@@ -113,7 +115,7 @@ $servers = get_user_servers($user_id);
                         }
                         
                         serverNameEl.textContent = data.server_name;
-                        channelsListEl.innerHTML = ''; // Clear loading state
+                        channelsListEl.innerHTML = '';
                         if (data.channels.length > 0) {
                             data.channels.forEach(channel => {
                                 const channelEl = document.createElement('div');
@@ -123,7 +125,6 @@ $servers = get_user_servers($user_id);
                                 channelEl.addEventListener('click', () => selectChannel(channel.id, channel.name));
                                 channelsListEl.appendChild(channelEl);
                             });
-                            // Automatically select the first channel
                             selectChannel(data.channels[0].id, data.channels[0].name);
                         } else {
                             channelsListEl.innerHTML = '<p style="color: var(--text-muted); padding: 0 16px;">Aucun canal trouvé.</p>';
@@ -140,13 +141,12 @@ $servers = get_user_servers($user_id);
             if (channelId === activeChannelId) return;
             activeChannelId = channelId;
 
-            // Update active state for channel list
+            if (messagePollingInterval) {
+                clearInterval(messagePollingInterval);
+            }
+
             document.querySelectorAll('.channel').forEach(c => {
-                if (c.dataset.channelId === channelId.toString()) {
-                    c.classList.add('active');
-                } else {
-                    c.classList.remove('active');
-                }
+                c.classList.toggle('active', c.dataset.channelId === channelId.toString());
             });
 
             channelNameEl.textContent = channelName;
@@ -157,39 +157,47 @@ $servers = get_user_servers($user_id);
             messageInput.focus();
 
             fetchMessages(channelId);
+            messagePollingInterval = setInterval(() => fetchMessages(channelId), 3000);
         }
 
         function fetchMessages(channelId) {
+            const wasScrolledToBottom = messagesListEl.scrollHeight - messagesListEl.clientHeight <= messagesListEl.scrollTop + 1;
+
             fetch(`get_messages.php?channel_id=${channelId}`)
                 .then(response => response.json())
                 .then(data => {
-                    messagesListEl.innerHTML = '';
+                    let newHTML = '';
                     if (data.error) {
-                        messagesListEl.innerHTML = `<p style="color: #f04747; text-align:center;">${data.error}</p>`;
-                        return;
-                    }
-                    if (data.length > 0) {
+                        newHTML = `<p style="color: #f04747; text-align:center;">${data.error}</p>`;
+                    } else if (data.length > 0) {
                         data.forEach(msg => {
-                            const msgEl = document.createElement('div');
-                            msgEl.classList.add('message');
-                            msgEl.innerHTML = `
-                                <div class="message-avatar"></div>
-                                <div class="message-content">
-                                    <span class="message-author">${escapeHTML(msg.username)}</span>
-                                    <div class="message-text">${escapeHTML(msg.message)}</div>
+                            newHTML += `
+                                <div class="message">
+                                    <div class="message-avatar"></div>
+                                    <div class="message-content">
+                                        <span class="message-author">${escapeHTML(msg.username)}</span>
+                                        <div class="message-text">${escapeHTML(msg.message)}</div>
+                                    </div>
                                 </div>
                             `;
-                            messagesListEl.appendChild(msgEl);
                         });
                     } else {
-                        messagesListEl.innerHTML = '<p style="text-align:center; color: var(--text-muted);">Aucun message. Soyez le premier à en envoyer un !</p>';
+                        newHTML = '<p style="text-align:center; color: var(--text-muted);">Aucun message. Soyez le premier à en envoyer un !</p>';
+                    }
+
+                    if (messagesListEl.innerHTML !== newHTML) {
+                        messagesListEl.innerHTML = newHTML;
+                        if (wasScrolledToBottom) {
+                            messagesListEl.scrollTop = messagesListEl.scrollHeight;
+                        }
                     }
-                    // Scroll to bottom
-                    messagesListEl.scrollTop = messagesListEl.scrollHeight;
                 })
                 .catch(error => {
                     console.error('Error fetching messages:', error);
-                    messagesListEl.innerHTML = '<p style="color: #f04747; text-align:center;">Erreur de chargement des messages.</p>';
+                    // Avoid replacing content on intermittent network errors during polling
+                    if (messagesListEl.innerHTML.includes('Chargement des messages...')) {
+                         messagesListEl.innerHTML = '<p style="color: #f04747; text-align:center;">Erreur de chargement des messages.</p>';
+                    }
                 });
         }
 
@@ -210,7 +218,7 @@ $servers = get_user_servers($user_id);
             .then(data => {
                 if (data.success) {
                     messageInput.value = '';
-                    fetchMessages(activeChannelId); // Refresh messages
+                    fetchMessages(activeChannelId); // Refresh messages immediately
                 } else {
                     alert('Erreur lors de l'envoi du message: ' + data.error);
                 }
@@ -222,7 +230,7 @@ $servers = get_user_servers($user_id);
         });
 
         function escapeHTML(str) {
-            return str.replace(/[&<>'"/]/g, function(match) {
+            return str.replace(/[&<>"']/g, function(match) {
                 return {
                     '&': '&amp;',
                     '<': '&lt;',