diff --git a/src/core/Form/Type/CollectionType.php b/src/core/Form/Type/CollectionType.php
index 3670c38..5c91d90 100644
--- a/src/core/Form/Type/CollectionType.php
+++ b/src/core/Form/Type/CollectionType.php
@@ -16,12 +16,23 @@ class CollectionType extends BaseCollectionType
     {
         parent::buildView($view, $form, $options);
 
+        $classes = [
+            'add_attr' => 'collection-add',
+            'delete_attr' => 'text-right',
+        ];
+
+        foreach ($classes as $key => $class) {
+            $options[$key]['class'] = $class.' '.($options[$key]['class'] ?? '');
+        }
+
         $view->vars = array_replace($view->vars, [
             'collection_name' => $options['collection_name'],
             'label_add' => $options['label_add'],
             'label_delete' => $options['label_delete'],
             'allow_add' => $options['allow_add'],
             'allow_delete' => $options['allow_delete'],
+            'add_attr' => $options['add_attr'],
+            'delete_attr' => $options['delete_attr'],
             'template_before_item' => $options['template_before_item'],
             'template_after_item' => $options['template_after_item'],
         ]);
@@ -37,6 +48,8 @@ class CollectionType extends BaseCollectionType
             'label_delete' => 'Delete',
             'template_before_item' => null,
             'template_after_item' => null,
+            'add_attr' => [],
+            'delete_attr' => [],
         ]);
     }
 
diff --git a/src/core/Resources/views/form/bootstrap_4_form_theme.html.twig b/src/core/Resources/views/form/bootstrap_4_form_theme.html.twig
index d937d6d..61dd5a3 100644
--- a/src/core/Resources/views/form/bootstrap_4_form_theme.html.twig
+++ b/src/core/Resources/views/form/bootstrap_4_form_theme.html.twig
@@ -78,6 +78,8 @@
 {% block collection_block_widget %}
     {% set allow_delete = allow_delete|default(false) %}
     {% set allow_add = allow_add|default(false) %}
+    {% set add_attr = allow_add|default({}) %}
+    {% set delete_attr = allow_add|default({}) %}
 
     <div data-collection="collection-{{ collection_name }}">
         {% for item in form.value %}
@@ -87,7 +89,7 @@
                 {% endfor %}
 
                 {% if allow_delete %}
-                    <div class="text-right">
+                    <div {% for k, v in delete_attr %}{{ k }}="{{ v }}">
                         <span data-collection-delete-container class="btn btn-sm btn-danger">
                             <span data-collection-delete="{{ loop.index }}">
                                 <span data-collection-delete="{{ loop.index }}" class="fa fa-trash"></span>
@@ -101,7 +103,7 @@
     </div>
 
     {% if allow_add %}
-        <div data-collection-add="collection-{{ collection_name }}" class="collection-add">
+        <div data-collection-add="collection-{{ collection_name }}" {% for k, v in add_attr %}{{ k }}="{{ v }}">
             <span class="btn btn-sm btn-primary" data-collection-add="collection-{{ collection_name }}">
                 <span data-collection-add="collection-{{ collection_name }}" class="fa fa-plus"></span>
                 {{ label_add|trans }}