diff --git a/declarationtva_view.php b/declarationtva_view.php
index f390ac8..ec15d50 100644
--- a/declarationtva_view.php
+++ b/declarationtva_view.php
@@ -560,30 +560,69 @@ function loadLineDetails(line) {
 }
 
 function confirmValidation(declarationId) {
-    // Create confirmation dialog
+    // Create a proper Dolibarr-style modal dialog
     var dialog = document.createElement("div");
-    dialog.style.cssText = "position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.5); z-index: 10000; display: flex; align-items: center; justify-content: center;";
+    dialog.id = "validationModal";
+    dialog.style.cssText = "position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.6); z-index: 10000; display: flex; align-items: center; justify-content: center; font-family: Arial, sans-serif;";
     
     var dialogContent = document.createElement("div");
-    dialogContent.style.cssText = "background: white; padding: 20px; border-radius: 5px; box-shadow: 0 4px 6px rgba(0,0,0,0.1); max-width: 500px; text-align: center;";
+    dialogContent.style.cssText = "background: white; border-radius: 8px; box-shadow: 0 10px 30px rgba(0,0,0,0.3); max-width: 500px; width: 90%; max-height: 90%; overflow: hidden;";
     
-    dialogContent.innerHTML = `
-        <h3>' . $langs->trans("ConfirmValidation") . '</h3>
-        <p>' . $langs->trans("ValidationConfirmationMessage") . '</p>
-        <div style="margin-top: 20px;">
-            <button onclick="proceedValidation(' . $id . '); this.parentElement.parentElement.parentElement.remove();" 
-                    style="background: #28a745; color: white; border: none; padding: 10px 20px; margin: 0 10px; border-radius: 3px; cursor: pointer;">
-                ' . $langs->trans("YesValidate") . '
-            </button>
-            <button onclick="this.parentElement.parentElement.parentElement.remove();" 
-                    style="background: #6c757d; color: white; border: none; padding: 10px 20px; margin: 0 10px; border-radius: 3px; cursor: pointer;">
-                ' . $langs->trans("Cancel") . '
-            </button>
+    // Header
+    var header = document.createElement("div");
+    header.style.cssText = "background: #f8f9fa; padding: 20px; border-bottom: 1px solid #dee2e6; display: flex; align-items: center;";
+    header.innerHTML = `
+        <div style="flex: 1;">
+            <h3 style="margin: 0; color: #495057; font-size: 18px; font-weight: 600;">' . $langs->trans("ConfirmValidation") . '</h3>
+        </div>
+        <button onclick="closeValidationModal()" style="background: none; border: none; font-size: 24px; color: #6c757d; cursor: pointer; padding: 0; width: 30px; height: 30px; display: flex; align-items: center; justify-content: center;">&times;</button>
+    `;
+    
+    // Body
+    var body = document.createElement("div");
+    body.style.cssText = "padding: 20px;";
+    body.innerHTML = `
+        <div style="display: flex; align-items: flex-start; margin-bottom: 20px;">
+            <div style="background: #fff3cd; border: 1px solid #ffeaa7; border-radius: 50%; width: 40px; height: 40px; display: flex; align-items: center; justify-content: center; margin-right: 15px; flex-shrink: 0;">
+                <span style="color: #856404; font-size: 18px; font-weight: bold;">!</span>
+            </div>
+            <div style="flex: 1;">
+                <p style="margin: 0; color: #495057; line-height: 1.5; font-size: 14px;">' . $langs->trans("ValidationConfirmationMessage") . '</p>
+            </div>
         </div>
     `;
     
+    // Footer
+    var footer = document.createElement("div");
+    footer.style.cssText = "background: #f8f9fa; padding: 15px 20px; border-top: 1px solid #dee2e6; display: flex; justify-content: flex-end; gap: 10px;";
+    footer.innerHTML = `
+        <button onclick="closeValidationModal()" style="background: #6c757d; color: white; border: none; padding: 8px 16px; border-radius: 4px; cursor: pointer; font-size: 14px; font-weight: 500;">
+            ' . $langs->trans("Cancel") . '
+        </button>
+        <button onclick="proceedValidation(' . $id . ')" style="background: #28a745; color: white; border: none; padding: 8px 16px; border-radius: 4px; cursor: pointer; font-size: 14px; font-weight: 500;">
+            ' . $langs->trans("YesValidate") . '
+        </button>
+    `;
+    
+    dialogContent.appendChild(header);
+    dialogContent.appendChild(body);
+    dialogContent.appendChild(footer);
     dialog.appendChild(dialogContent);
     document.body.appendChild(dialog);
+    
+    // Add escape key handler
+    document.addEventListener("keydown", function(e) {
+        if (e.key === "Escape") {
+            closeValidationModal();
+        }
+    });
+}
+
+function closeValidationModal() {
+    var modal = document.getElementById("validationModal");
+    if (modal) {
+        modal.remove();
+    }
 }
 
 function proceedValidation(declarationId) {