diff --git a/js/gamutable.es6.js b/js/gamutable.es6.js
index 21a179d..d75708a 100644
--- a/js/gamutable.es6.js
+++ b/js/gamutable.es6.js
@@ -221,7 +221,9 @@ let monTableau = {
 					let config = data.shift();
 					this.header = config.header;
 					this.crayons = config.crayons;
-					this.classes = config.classes;
+					if (config.classes !== undefined) {
+						this.classes = config.classes;
+					}
 					this.table = data;
 					if (data.length && data[0].search) {
 						this.champ_search = 'search';
@@ -235,7 +237,9 @@ let monTableau = {
 					let config = data.shift();
 					this.header = config.header;
 					this.crayons = config.crayons;
-					this.classes = config.classes;
+					if (config.classes !== undefined) {
+						this.classes = config.classes;
+					}
 					if (parseInt(id) > 0) {
 						let i = this.table.findIndex((ligne) => ligne.html.id === parseInt(id));
 						Vue.set(this.table, i, data[0]);
diff --git a/js/gamutable.js b/js/gamutable.js
index 2a7cc40..e669403 100644
--- a/js/gamutable.js
+++ b/js/gamutable.js
@@ -259,7 +259,11 @@ var monTableau = {
           var config = data.shift();
           this.header = config.header;
           this.crayons = config.crayons;
-          this.classes = config.classes;
+
+          if (config.classes !== undefined) {
+            this.classes = config.classes;
+          }
+
           this.table = data;
 
           if (data.length && data[0].search) {
@@ -276,7 +280,10 @@ var monTableau = {
         var config = data.shift();
         _this2.header = config.header;
         _this2.crayons = config.crayons;
-        _this2.classes = config.classes;
+
+        if (config.classes !== undefined) {
+          _this2.classes = config.classes;
+        }
 
         if (parseInt(id) > 0) {
           var i = _this2.table.findIndex(function (ligne) {