diff --git a/assets/css/style.css b/assets/css/style.css
index 507dc9e..7555e29 100644
--- a/assets/css/style.css
+++ b/assets/css/style.css
@@ -590,7 +590,11 @@ section h2 {
 
 /* Table des matières */
 #table-of-contents {
-  /* Comportement normal de scroll */
+  max-height: calc(100vh - 200px);
+  overflow-y: auto;
+  position: sticky;
+  top: 100px;
+  align-self: flex-start;
 }
 
 #toc-nav {
@@ -599,10 +603,12 @@ section h2 {
 
 #toc-nav ul {
   list-style: none;
+  padding-left: 0;
 }
 
 #toc-nav li {
   margin-bottom: 0.5rem;
+  list-style: none;
 }
 
 #toc-nav a {
@@ -621,8 +627,9 @@ section h2 {
 }
 
 #toc-nav ul ul {
-  margin-left: 1rem;
+  margin-left: 0;
   margin-top: 0.5rem;
+  padding-left: 0;
 }
 
 #toc-nav ul ul a {
@@ -633,6 +640,8 @@ section h2 {
 /* Zone d'écriture */
 #design-journal {
   min-height: 600px;
+  max-height: calc(100vh - 200px);
+  overflow-y: auto;
 }
 
 #journal-editor {
@@ -644,7 +653,6 @@ section h2 {
   border: none;
   background: var(--surface-color);
   color: var(--text-color);
-  resize: vertical;
   white-space: pre-wrap;
   word-wrap: break-word;
   overflow-wrap: break-word;
@@ -693,7 +701,10 @@ section h2 {
 #ai-assistant {
   display: flex;
   flex-direction: column;
-  /* Comportement normal de scroll */
+  max-height: calc(100vh - 200px);
+  position: sticky;
+  top: 100px;
+  align-self: flex-start;
 }
 
 /* Styles pour "Coming Soon" */
diff --git a/assets/js/app.js b/assets/js/app.js
index 4681ff9..3d0e755 100644
--- a/assets/js/app.js
+++ b/assets/js/app.js
@@ -434,7 +434,6 @@ class ConceptionAssistant {
     const content = this.editor.innerText;
     const lines = content.split('\n');
     const toc = [];
-    let tocHtml = '';
 
     // Remove existing anchors
     const existingAnchors = this.editor.querySelectorAll('.heading-anchor');
@@ -451,29 +450,42 @@ class ConceptionAssistant {
       }
     }
 
-    // Temporarily disabled to avoid disrupting typing
-    // this.addHeadingAnchors(lines, toc);
-
+    let tocHtml = '';
     if (toc.length > 0) {
-      tocHtml = '<ul>';
-      let currentLevel = 0;
+      // Nouvelle génération de TOC avec indentation correcte
+      let previousLevel = 0;
 
-      for (const item of toc) {
-        if (item.level > currentLevel) {
-          for (let i = currentLevel; i < item.level - 1; i++) {
+      for (let i = 0; i < toc.length; i++) {
+        const item = toc[i];
+
+        // Ouvrir les listes nécessaires
+        if (item.level > previousLevel) {
+          for (let j = previousLevel; j < item.level; j++) {
             tocHtml += '<ul>';
           }
-        } else if (item.level < currentLevel) {
-          for (let i = item.level; i < currentLevel; i++) {
-            tocHtml += '</ul>';
+        }
+        // Fermer les listes nécessaires
+        else if (item.level < previousLevel) {
+          for (let j = item.level; j < previousLevel; j++) {
+            tocHtml += '</ul></li>';
           }
         }
+        // Même niveau, fermer le li précédent
+        else if (i > 0) {
+          tocHtml += '</li>';
+        }
 
-        tocHtml += `<li><a href="#${item.id}" onclick="app.scrollToHeading('${item.title}'); return false;">${item.title}</a></li>`;
-        currentLevel = item.level;
+        // Ajouter l'élément avec indentation CSS
+        const indent = (item.level - 1) * 1; // 1rem par niveau
+        tocHtml += `<li style="margin-left: ${indent}rem;"><a href="#${item.id}" onclick="app.scrollToHeading('${item.title.replace(/'/g, "\\'")}'); return false;">${item.title}</a>`;
+
+        previousLevel = item.level;
       }
 
-      tocHtml += '</ul>';
+      // Fermer toutes les listes restantes
+      for (let j = 0; j < previousLevel; j++) {
+        tocHtml += '</li></ul>';
+      }
     } else {
       tocHtml = '<div class="toc-placeholder"><p>Add headings (# ## ###) to your journal to generate the table of contents.</p></div>';
     }
@@ -505,18 +517,21 @@ class ConceptionAssistant {
 
   scrollToHeading(title) {
     try {
-      // Simpler and more robust method: search text directly in editor
       const content = this.editor.innerText;
       const lines = content.split('\n');
 
-      // Find the line index corresponding to the title
+      // Find the line index and calculate character position
       let targetLineIndex = -1;
+      let charPosition = 0;
+
       for (let i = 0; i < lines.length; i++) {
         const line = lines[i].trim();
         if (line.startsWith('#') && line.replace(/^#+\s*/, '') === title) {
           targetLineIndex = i;
           break;
         }
+        // Count characters including newlines
+        charPosition += lines[i].length + 1; // +1 for \n
       }
 
       if (targetLineIndex === -1) {
@@ -524,37 +539,56 @@ class ConceptionAssistant {
         return;
       }
 
-      // Calculate approximate line position
-      const editorStyles = window.getComputedStyle(this.editor);
-      const lineHeight = parseFloat(editorStyles.lineHeight) || 20;
-      const paddingTop = parseFloat(editorStyles.paddingTop) || 0;
+      // Create a range at the target position to get accurate coordinates
+      const selection = window.getSelection();
+      const range = document.createRange();
 
-      // Calculate scroll position based on line number
-      const targetScrollPosition = (targetLineIndex * lineHeight) + paddingTop;
+      // Find the text node at the character position
+      const walker = document.createTreeWalker(
+        this.editor,
+        NodeFilter.SHOW_TEXT,
+        null
+      );
 
-      // Determine if editor or window should be scrolled
-      const editorRect = this.editor.getBoundingClientRect();
-      const editorHasScroll = this.editor.scrollHeight > this.editor.clientHeight;
+      let currentChar = 0;
+      let targetNode = null;
+      let offsetInNode = 0;
 
-      if (editorHasScroll) {
-        // Scroll within editor
-        this.editor.scrollTo({
-          top: Math.max(0, targetScrollPosition - 60),
-          behavior: 'smooth'
-        });
-      } else {
-        // Scroll entire page
-        const editorTop = this.editor.offsetTop;
-        const windowScrollTarget = editorTop + targetScrollPosition - 100;
+      while (walker.nextNode()) {
+        const node = walker.currentNode;
+        const nodeLength = node.textContent.length;
 
-        window.scrollTo({
-          top: Math.max(0, windowScrollTarget),
-          behavior: 'smooth'
-        });
+        if (currentChar + nodeLength >= charPosition) {
+          targetNode = node;
+          offsetInNode = charPosition - currentChar;
+          break;
+        }
+        currentChar += nodeLength;
       }
 
-      // Optional: temporarily highlight the title
-      this.highlightHeading(title);
+      if (targetNode) {
+        // Set range at the target position
+        range.setStart(targetNode, Math.min(offsetInNode, targetNode.textContent.length));
+        range.setEnd(targetNode, Math.min(offsetInNode, targetNode.textContent.length));
+
+        // Get the bounding rectangle of the range
+        const rect = range.getBoundingClientRect();
+
+        // Scroll to the element - use the parent container (#design-journal)
+        const journalSection = document.getElementById('design-journal');
+        const sectionRect = journalSection.getBoundingClientRect();
+        const scrollOffset = rect.top - sectionRect.top + journalSection.scrollTop - 100;
+
+        journalSection.scrollTo({
+          top: Math.max(0, scrollOffset),
+          behavior: 'smooth'
+        });
+
+        // Temporarily highlight the heading
+        selection.removeAllRanges();
+        selection.addRange(range);
+        setTimeout(() => selection.removeAllRanges(), 1000);
+      }
 
       this.showNotification(`Navigating to: ${title}`, 'success');
 
@@ -1297,8 +1331,8 @@ class ConceptionAssistant {
     const mainElement = document.querySelector('main');
 
     if (!this.isPreviewMode) {
-      // Switch to preview mode
-      this.originalContent = this.editor.innerHTML;
+      // Switch to preview mode - Save innerText instead of innerHTML
+      this.originalContent = this.editor.innerText;
       const markdownContent = this.editor.innerText;
 
       // Add preview-mode class to main to adjust grid layout
@@ -1392,9 +1426,9 @@ class ConceptionAssistant {
       this.showNotification('Preview mode activated', 'success');
 
     } else {
-      // Return to edit mode
+      // Return to edit mode - Restore innerText instead of innerHTML
       this.editor.contentEditable = true;
-      this.editor.innerHTML = this.originalContent;
+      this.editor.innerText = this.originalContent;
       this.editor.style.background = '';
       this.editor.style.border = '';
       this.editor.style.borderRadius = '';
diff --git a/routes/ai.js b/routes/ai.js
index 0112c21..6529c37 100644
--- a/routes/ai.js
+++ b/routes/ai.js
@@ -1,5 +1,6 @@
 const express = require('express');
 const router = express.Router();
+const https = require('https');
 require('dotenv').config({ path: './config/.env' });
 
 // Mistral AI Configuration
@@ -27,8 +28,18 @@ function checkAIEnabled(req, res, next) {
   next();
 }
 
-// Function to call Mistral API
+// Create a custom HTTPS agent with longer timeouts
+const httpsAgent = new https.Agent({
+  keepAlive: true,
+  timeout: 120000, // 120 seconds
+  maxSockets: 5
+});
+
+// Function to call Mistral API with timeout handling
 async function callMistralAPI(messages, temperature = null) {
+  const controller = new AbortController();
+  const timeoutId = setTimeout(() => controller.abort(), 120000); // 120 seconds timeout
+
   try {
     const response = await fetch(`${MISTRAL_BASE_URL}/chat/completions`, {
       method: 'POST',
@@ -42,9 +53,13 @@ async function callMistralAPI(messages, temperature = null) {
         temperature: temperature !== null ? temperature : parseFloat(process.env.AI_TEMPERATURE) || 0.3,
         max_tokens: parseInt(process.env.AI_MAX_TOKENS) || 35000,
         top_p: parseFloat(process.env.AI_TOP_P) || 0.85
-      })
+      }),
+      signal: controller.signal,
+      agent: httpsAgent
     });
 
+    clearTimeout(timeoutId);
+
     if (!response.ok) {
       const error = await response.text();
       throw new Error(`Mistral API Error: ${response.status} - ${error}`);
@@ -53,7 +68,20 @@ async function callMistralAPI(messages, temperature = null) {
     const data = await response.json();
     return data.choices[0].message.content;
   } catch (error) {
+    clearTimeout(timeoutId);
     console.error('Mistral API Error:', error);
+
+    // Better error messages
+    if (error.name === 'AbortError') {
+      throw new Error('Request timeout: The API took too long to respond (>120s)');
+    }
+    if (error.cause && error.cause.code === 'UND_ERR_HEADERS_TIMEOUT') {
+      throw new Error('Connection timeout: Unable to connect to Mistral API. Check your network or API endpoint.');
+    }
+    if (error.cause && error.cause.code === 'ECONNREFUSED') {
+      throw new Error('Connection refused: Cannot reach Mistral API endpoint.');
+    }
+
     throw error;
   }
 }
@@ -307,17 +335,22 @@ router.post('/liberty-mode', checkAIEnabled, async (req, res) => {
             3. Develop existing ideas with the allowed creativity
             4. Maintain logical structure
 
-            MANDATORY RESPONSE IN 2 PARTS SEPARATED BY "---SPLIT---":
+            MANDATORY RESPONSE FORMAT - Use code blocks with triple backticks:
 
-            ## Analysis (Iteration ${i + 1}/${maxIterations})
-            [Explain the improvements made, sections added, reasoning]
+            First, write your comment explaining the improvements inside a code block labeled "comment${i + 1}":
+            - What sections were added
+            - What was enhanced
+            - Reasoning behind changes
 
-            ---SPLIT---
+            Then, write the complete improved markdown document inside a code block labeled "document".
 
-            [THE COMPLETE AND IMPROVED MARKDOWN DOCUMENT - WITHOUT "## Document" TITLE - DIRECTLY THE CONTENT]
+            Example format:
+            First block: comment${i + 1}
+            Second block: document
 
             Focus: ${focus}
-            Precision: ${precisionPercent}%`
+            Precision: ${precisionPercent}%
+            Iteration: ${i + 1}/${maxIterations}`
           },
           {
             role: 'user',
@@ -330,20 +363,36 @@ router.post('/liberty-mode', checkAIEnabled, async (req, res) => {
 
         const result = await callMistralAPI(messages, temperature);
 
-        // Separate explanation from markdown
-        const parts = result.split('---SPLIT---');
+        // Extract code blocks
+        const commentRegex = /```comment\d+\s*([\s\S]*?)```/;
+        const documentRegex = /```document\s*([\s\S]*?)```/;
+
+        const commentMatch = result.match(commentRegex);
+        const documentMatch = result.match(documentRegex);
 
         let explanation = '';
         let newMarkdown = currentContent; // Default, keep old content
 
-        if (parts.length >= 2) {
-          explanation = parts[0].trim();
-          newMarkdown = parts[1].trim();
+        if (commentMatch && commentMatch[1]) {
+          explanation = commentMatch[1].trim();
+        }
+
+        if (documentMatch && documentMatch[1]) {
+          newMarkdown = documentMatch[1].trim();
           // Update for next iteration
           currentContent = newMarkdown;
-        } else {
-          // Fallback if no split found
-          explanation = result;
+        }
+
+        // Fallback: if no code blocks found, try old format for compatibility
+        if (!commentMatch && !documentMatch) {
+          const parts = result.split('---SPLIT---');
+          if (parts.length >= 2) {
+            explanation = parts[0].trim();
+            newMarkdown = parts[1].trim();
+            currentContent = newMarkdown;
+          } else {
+            explanation = result;
+          }
         }
 
         // Send this iteration's response