diff --git a/main/admin/access_url_edit_courses_to_url.php b/main/admin/access_url_edit_courses_to_url.php
index 9f0ffc0c69..cd6d2ff61b 100755
--- a/main/admin/access_url_edit_courses_to_url.php
+++ b/main/admin/access_url_edit_courses_to_url.php
@@ -224,13 +224,19 @@ $url_list = UrlManager::get_url_data();
 					<?php
 					if($ajax_search) {
 						?>
-						<button class="btn btn-default" type="button" onclick="remove_item(document.getElementById('destination_users'))" ></button>
+						<button class="btn btn-default" type="button" onclick="remove_item(document.getElementById('destination_users'))" >
+                            <i class="fa fa-arrow-left"></i>
+						</button>
 					<?php
 					} else {
 						?>
-						<button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('origin_users'), document.getElementById('destination_users'))" ><i class="fa fa-plus"></i></button>
+						<button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('origin_users'), document.getElementById('destination_users'))" >
+                            <i class="fa fa-arrow-right"></i>
+						</button>
 						<br /><br />
-						<button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('destination_users'), document.getElementById('origin_users'))" ><i class="fa fa-minus"></i></button>
+						<button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('destination_users'), document.getElementById('origin_users'))" >
+                            <i class="fa fa-arrow-left"></i>
+						</button>
 					<?php
 					}
 					?>
@@ -254,9 +260,9 @@ $url_list = UrlManager::get_url_data();
 					<br />
 					<?php
 					if(isset($_GET['add']))
-						echo '<button class="save" onclick="valide()" >'.get_lang('AddCoursesToURL').'</button>';
+						echo '<button class="btn btn-default" onclick="valide()" >'.get_lang('AddCoursesToURL').'</button>';
 					else
-						echo '<button class="save" onclick="valide()" >'.get_lang('EditCoursesToURL').'</button>';
+						echo '<button class="btn btn-default" onclick="valide()" >'.get_lang('EditCoursesToURL').'</button>';
 					?>
 				</td>
 			</tr>
diff --git a/main/admin/access_url_edit_usergroup_to_url.php b/main/admin/access_url_edit_usergroup_to_url.php
index 9dc2dc2f77..93f4622215 100755
--- a/main/admin/access_url_edit_usergroup_to_url.php
+++ b/main/admin/access_url_edit_usergroup_to_url.php
@@ -218,13 +218,19 @@ if (!empty($errorMsg)) {
   <?php
   if ($ajax_search) {
 	?>
-	<button class="arrowl" type="button" onclick="remove_item(document.getElementById('destination_users'))" ></button>
+	<button class="btn btn-default" type="button" onclick="remove_item(document.getElementById('destination_users'))" >
+        <i class="fa fa-arrow-left"></i>
+	</button>
   	<?php
   } else {
   	?>
-	<button class="arrowr" type="button" onclick="moveItem(document.getElementById('origin_users'), document.getElementById('destination_users'))" ></button>
+	<button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('origin_users'), document.getElementById('destination_users'))" >
+        <i class="fa fa-arrow-right"></i>
+	</button>
 	<br /><br />
-	<button class="arrowl" type="button" onclick="moveItem(document.getElementById('destination_users'), document.getElementById('origin_users'))" ></button>
+	<button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('destination_users'), document.getElementById('origin_users'))" >
+        <i class="fa fa-arrow-left"></i>
+	</button>
 	<?php
   }
   ?>
diff --git a/main/admin/access_url_edit_users_to_url.php b/main/admin/access_url_edit_users_to_url.php
index 8ed43baaad..a199d4c59d 100755
--- a/main/admin/access_url_edit_users_to_url.php
+++ b/main/admin/access_url_edit_users_to_url.php
@@ -272,11 +272,18 @@ if (!empty($errorMsg)) {
   </td>
   <td width="10%" valign="middle" align="center">
     <?php if ($ajax_search) { ?>
-        <button class="arrowl" type="button" onclick="remove_item(document.getElementById('destination_users'))"> </button>
+        <button class="btn btn-default" type="button" onclick="remove_item(document.getElementById('destination_users'))">
+            <i class="fa fa-arrow-left"></i>
+        </button>
     <?php } else { ?>
-        <button class="arrowr" type="button" onclick="moveItem(document.getElementById('origin_users'), document.getElementById('destination_users'))" ></button>
+        <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('origin_users'), document.getElementById('destination_users'))" >
+            <i class="fa fa-arrow-right"></i>
+        </button>
         <br /><br />
-        <button class="arrowl" type="button" onclick="moveItem(document.getElementById('destination_users'), document.getElementById('origin_users'))" ></button>
+        <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('destination_users'), document.getElementById('origin_users'))" >
+            <i class="fa fa-arrow-left"></i>
+
+        </button>
     <?php } ?>
 	<br /><br /><br /><br /><br /><br />
   </td>
diff --git a/main/admin/add_courses_to_usergroup.php b/main/admin/add_courses_to_usergroup.php
index f5bf4d13fb..2778dc56c0 100755
--- a/main/admin/add_courses_to_usergroup.php
+++ b/main/admin/add_courses_to_usergroup.php
@@ -271,13 +271,19 @@ if (!empty($errorMsg)) {
   <?php
   if ($ajax_search) {
   ?>
-    <button class="arrowl" type="button" onclick="remove_item(document.getElementById('elements_in'))" ></button>
+    <button class="btn bt-default" type="button" onclick="remove_item(document.getElementById('elements_in'))" >
+        <i class="fa fa-arrow-left"></i>
+    </button>
   <?php
   } else {
   ?>
-    <button class="arrowr" type="button" onclick="moveItem(document.getElementById('elements_not_in'), document.getElementById('elements_in'))" onclick="moveItem(document.getElementById('elements_not_in'), document.getElementById('elements_in'))"></button>
+    <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('elements_not_in'), document.getElementById('elements_in'))" onclick="moveItem(document.getElementById('elements_not_in'), document.getElementById('elements_in'))">
+        <i class="fa fa-arrow-right"></i>
+    </button>
     <br /><br />
-    <button class="arrowl" type="button" onclick="moveItem(document.getElementById('elements_in'), document.getElementById('elements_not_in'))" onclick="moveItem(document.getElementById('elements_in'), document.getElementById('elements_not_in'))"></button>
+    <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('elements_in'), document.getElementById('elements_not_in'))" onclick="moveItem(document.getElementById('elements_in'), document.getElementById('elements_not_in'))">
+        <i class="fa fa-arrow-left"></i>
+    </button>
     <?php
   }
   ?>
@@ -294,7 +300,7 @@ if (!empty($errorMsg)) {
     <td colspan="3" align="center">
         <br />
         <?php
-        echo '<button class="save" type="button" value="" onclick="valide()" >'.get_lang('SubscribeClassToCourses').'</button>';
+        echo '<button class="btn btn-primary" type="button" value="" onclick="valide()" >'.get_lang('SubscribeClassToCourses').'</button>';
         ?>
     </td>
 </tr>
diff --git a/main/admin/add_many_session_to_category.php b/main/admin/add_many_session_to_category.php
index 95f6879d61..adc47ec6b1 100755
--- a/main/admin/add_many_session_to_category.php
+++ b/main/admin/add_many_session_to_category.php
@@ -230,12 +230,16 @@ if(!empty($OkMsg)) {
 <?php unset($nosessionCourses); ?>
   </td>
   <td width="10%" valign="middle" align="center">
-  	<button class="arrowr" type="button" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))"></button>
+  	<button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))">
+        <i class="fa fa-arrow-left"></i>
+    </button>
 	<br /><br />
-	<button class="arrowl" type="button" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))"></button>
+	<button class="btn  btn-default" type="button" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))">
+        <i class="fa fa-arrow-right"></i>
+	</button>
 	<br /><br /><br /><br /><br /><br />
 	<?php
-		echo '<button class="save" type="button" value="" onclick="valide()" >'.get_lang('SubscribeSessionsToCategory').'</button>';
+		echo '<button class="btn btn-primary" type="button" value="" onclick="valide()" >'.get_lang('SubscribeSessionsToCategory').'</button>';
 	?>
   </td>
   <td width="45%" align="center">
diff --git a/main/admin/add_sessions_to_promotion.php b/main/admin/add_sessions_to_promotion.php
index d5ff7a8bfe..884da89011 100755
--- a/main/admin/add_sessions_to_promotion.php
+++ b/main/admin/add_sessions_to_promotion.php
@@ -231,13 +231,19 @@ if (!empty($errorMsg)) {
   <?php
   if ($ajax_search) {
   ?>
-    <button class="arrowl" type="button" onclick="remove_item(document.getElementById('session_in_promotion'))" ></button>
+    <button class="btn btn-default" type="button" onclick="remove_item(document.getElementById('session_in_promotion'))" >
+        <i class="fa fa-arrow-left"></i>
+    </button>
   <?php
   } else {
   ?>
-    <button class="arrowr" type="button" onclick="moveItem(document.getElementById('session_not_in_promotion'), document.getElementById('session_in_promotion'))" onclick="moveItem(document.getElementById('session_not_in_promotion'), document.getElementById('session_in_promotion'))"></button>
+    <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('session_not_in_promotion'), document.getElementById('session_in_promotion'))" onclick="moveItem(document.getElementById('session_not_in_promotion'), document.getElementById('session_in_promotion'))">
+        <i class="fa fa-arrow-right"></i>
+    </button>
     <br /><br />
-    <button class="arrowl" type="button" onclick="moveItem(document.getElementById('session_in_promotion'), document.getElementById('session_not_in_promotion'))" onclick="moveItem(document.getElementById('session_in_promotion'), document.getElementById('session_not_in_promotion'))"></button>
+    <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('session_in_promotion'), document.getElementById('session_not_in_promotion'))" onclick="moveItem(document.getElementById('session_in_promotion'), document.getElementById('session_not_in_promotion'))">
+        <i class="fa fa-arrow-left"></i>
+    </button>
     <?php
   }
   ?>
@@ -260,7 +266,7 @@ if (!empty($errorMsg)) {
     <td colspan="3" align="center">
         <br />
         <?php
-        echo '<button class="save" type="button" value="" onclick="valide()" >'.get_lang('SubscribeSessionsToPromotion').'</button>';
+        echo '<button class="btn btn-primary" type="button" value="" onclick="valide()" >'.get_lang('SubscribeSessionsToPromotion').'</button>';
         ?>
     </td>
 </tr>
diff --git a/main/admin/add_sessions_to_usergroup.php b/main/admin/add_sessions_to_usergroup.php
index 2019aa0e54..d814845e16 100755
--- a/main/admin/add_sessions_to_usergroup.php
+++ b/main/admin/add_sessions_to_usergroup.php
@@ -276,13 +276,19 @@ if(!empty($errorMsg)) {
   <?php
   if ($ajax_search) {
   ?>
-    <button class="arrowl" type="button" onclick="remove_item(document.getElementById('elements_in'))" ></button>
+    <button class="btn btn-default" type="button" onclick="remove_item(document.getElementById('elements_in'))" >
+        <i class="fa fa-arrow-left"></i>
+    </button>
   <?php
   } else {
   ?>
-    <button class="arrowr" type="button" onclick="moveItem(document.getElementById('elements_not_in'), document.getElementById('elements_in'))" onclick="moveItem(document.getElementById('elements_not_in'), document.getElementById('elements_in'))"></button>
+    <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('elements_not_in'), document.getElementById('elements_in'))" onclick="moveItem(document.getElementById('elements_not_in'), document.getElementById('elements_in'))">
+        <i class="fa fa-arrow-right"></i>
+    </button>
     <br /><br />
-    <button class="arrowl" type="button" onclick="moveItem(document.getElementById('elements_in'), document.getElementById('elements_not_in'))" onclick="moveItem(document.getElementById('elements_in'), document.getElementById('elements_not_in'))"></button>
+    <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('elements_in'), document.getElementById('elements_not_in'))" onclick="moveItem(document.getElementById('elements_in'), document.getElementById('elements_not_in'))">
+        <i class="fa fa-arrow-left"></i>
+    </button>
     <?php
   }
   ?>
@@ -299,7 +305,7 @@ if(!empty($errorMsg)) {
     <td colspan="3" align="center">
         <br />
         <?php
-        echo '<button class="save" type="button" value="" onclick="valide()" >'.get_lang('SubscribeClassToSessions').'</button>';
+        echo '<button class="btn btn-primary" type="button" value="" onclick="valide()" >'.get_lang('SubscribeClassToSessions').'</button>';
         ?>
     </td>
 </tr>
diff --git a/main/admin/add_users_to_usergroup.php b/main/admin/add_users_to_usergroup.php
index be58bf505a..b337a2ed31 100755
--- a/main/admin/add_users_to_usergroup.php
+++ b/main/admin/add_users_to_usergroup.php
@@ -431,7 +431,7 @@ if (!empty($errorMsg)) {
 </div>
 
 <?php
-    echo '<button class="btn btn-primary" type="button" value="" onclick="valide()" ><i class="fa fa-plus"></i>'.
+    echo '<button class="btn btn-primary" type="button" value="" onclick="valide()" ><i class="fa fa-check"></i>'.
         get_lang('SubscribeUsersToClass').'</button>';
 ?>
 </form>
diff --git a/main/admin/dashboard_add_courses_to_user.php b/main/admin/dashboard_add_courses_to_user.php
index 9b0d76bf51..db4fbde051 100755
--- a/main/admin/dashboard_add_courses_to_user.php
+++ b/main/admin/dashboard_add_courses_to_user.php
@@ -265,12 +265,16 @@ if(!empty($msg)) {
   </td>
 
   <td width="10%" valign="middle" align="center">
-  	<button class="arrowr" type="button" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))"></button>
+  	<button class="btn-default" type="button" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))">
+        <i class="fa fa-arrow-right"></i>
+  	</button>
 	<br /><br />
-	<button class="arrowl" type="button" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))"></button>
+	<button class="btn-default" type="button" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))">
+        <i class="fa fa-arrow-left"></i>
+	</button>
 	<br /><br /><br /><br /><br /><br />
 	<?php
-		echo '<button class="save" type="button" value="" onclick="valide()" >'.$tool_name.'</button>';
+		echo '<button class="btn btn-primary" type="button" value="" onclick="valide()" >'.$tool_name.'</button>';
 	?>
   </td>
   <td width="45%" align="center">
diff --git a/main/admin/dashboard_add_sessions_to_user.php b/main/admin/dashboard_add_sessions_to_user.php
index 1f921c68b9..9d7c0234bb 100755
--- a/main/admin/dashboard_add_sessions_to_user.php
+++ b/main/admin/dashboard_add_sessions_to_user.php
@@ -263,21 +263,27 @@ $result	= Database::query($sql);
                     <?php
                     if ($ajax_search) {
                         ?>
-                        <button class="arrowl" type="button" onclick="remove_item(document.getElementById('destination'))"></button>
+                        <button class="btn btn-default" type="button" onclick="remove_item(document.getElementById('destination'))">
+                            <i class="fa fa-arrow-left"></i>
+                        </button>
                     <?php
                     }
                     else
                     {
                         ?>
-                        <button class="arrowr" type="button" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))"></button>
+                        <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))">
+                            <i class="fa fa-arrow-right"></i>
+                        </button>
                         <br /><br />
-                        <button class="arrowl" type="button" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))"></button>
+                        <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))">
+                            <i class="fa fa-arrow-left"></i>
+                        </button>
                     <?php
                     }
                     ?>
                     <br /><br /><br /><br /><br /><br />
                     <?php
-                    echo '<button class="save" type="button" value="" onclick="valide()" >'.$tool_name.'</button>';
+                    echo '<button class="btn btn-primary" type="button" value="" onclick="valide()" >'.$tool_name.'</button>';
                     ?>
                 </td>
                 <td width="45%" align="center">
diff --git a/main/admin/event_type.php b/main/admin/event_type.php
index da4721cc8e..0674597575 100755
--- a/main/admin/event_type.php
+++ b/main/admin/event_type.php
@@ -306,9 +306,9 @@ echo Display::actions($action_array);
 <form method="POST" onSubmit="return submitForm(); ">
     <div class="row">
 
-    <div class="span12" id="event_list_group">
+    <div class="col-md-12" id="event_list_group">
         <h4><?php echo get_lang('Events'); ?></h4>
-        <select class="span6" multiple="1" id="eventList" onchange="confirmMessage(this.name); return false;" name="eventList">
+        <select class="col-md-6" multiple="1" id="eventList" onchange="confirmMessage(this.name); return false;" name="eventList">
         <?php
         foreach ($event_config as $key => $config) {
             echo '<option value="' . $key . '">' . $config['name_lang_var'] . '</option>';
@@ -317,21 +317,21 @@ echo Display::actions($action_array);
         </select>
     </div>
 
-    <div class="span4">
+    <div class="col-md-4">
         <h4><?php echo get_lang('Users'); ?></h4>
         <select multiple="1" id="usersList" class="span3 registration_case"></select>
     </div>
-    <div class="span4">
+    <div class="col-md-4">
         <div class="registration_case">
-            <button class="arrowr" onclick='moveUsers($("#usersList"),$("#usersSubList")); return false;'></button>
+            <button class="btn btn-default" onclick='moveUsers($("#usersList"),$("#usersSubList")); return false;'><i class="fa fa-arrow-left"></i></button>
             <br />
             <br />
-            <button class="arrowl" onclick='moveUsers($("#usersSubList"),$("#usersList")); return false;'></button>
+            <button class="btn btn-default" onclick='moveUsers($("#usersSubList"),$("#usersList")); return false;'><i class="fa fa-arrow-right"></i></button>
         </div>
     </div>
-    <div class="span4">
+    <div class="col-md-4">
         <h4><?php echo get_lang('ToBeWarnedUserList'); ?></h4>
-        <select class="span3" multiple="1" id="usersSubList" class="registration_case"></select>
+        <select class="col-md-3" multiple="1" id="usersSubList" class="registration_case"></select>
     </div>
     </div>
 
@@ -362,7 +362,7 @@ echo Display::actions($action_array);
     <label for="eventSubject">
         <h4><?php echo get_lang('Subject'); ?></h4>
     </label>
-    <input class="span6" type="text" id="eventSubject" name="eventSubject" onchange="contentChanged(); return false;" />
+    <input class="col-md-6" type="text" id="eventSubject" name="eventSubject" onchange="contentChanged(); return false;" />
     <br /><br />
     <table>
         <tr>
@@ -375,7 +375,7 @@ echo Display::actions($action_array);
         </tr>
         <tr>
             <td>
-                <textarea class="span6" rows="10" name="eventMessage" id="eventMessage" onchange="contentChanged(); return false;">
+                <textarea class="col-md-6" rows="10" name="eventMessage" id="eventMessage" onchange="contentChanged(); return false;">
                 </textarea>
             </td>
             <td class="available_keys">
@@ -384,7 +384,7 @@ echo Display::actions($action_array);
         </tr>
     </table>
     <br /><br />
-    <input type="submit" value="<?php echo get_lang('Save'); ?>" />
+    <input class="btn btn-primary" type="submit" value="<?php echo get_lang('Save'); ?>" />
 
 </form>
 <?php
diff --git a/main/admin/session_course_user.php b/main/admin/session_course_user.php
index e9c604a1b8..1a712fbe4f 100755
--- a/main/admin/session_course_user.php
+++ b/main/admin/session_course_user.php
@@ -180,12 +180,16 @@ unset($Courses);
 
                 </select></td>
             <td width="10%" valign="middle" align="center">
-                <button class="arrowr" type="button" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))"></button>
+                <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))" onclick="moveItem(document.getElementById('origin'), document.getElementById('destination'))">
+                    <i class="fa fa-arrow-right"></i>
+                </button>
                 <br /><br />
-                <button class="arrowl" type="button" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))"></button>
+                <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))" onclick="moveItem(document.getElementById('destination'), document.getElementById('origin'))">
+                    <i class="fa fa-arrow-left"></i>
+                </button>
                 <br /><br /><br /><br /><br /><br />
                 <?php
-                echo '<button class="save" type="button" value="" onclick="valide()" >'.get_lang('EditSessionCourses').'</button>';
+                echo '<button class="btn btn-primary" type="button" value="" onclick="valide()" >'.get_lang('EditSessionCourses').'</button>';
                 ?>
             </td>
             <td width="45%" align="center"><select id='destination' name="SessionCoursesList[]" multiple="multiple" size="20" style="width:320px;">
diff --git a/main/inc/lib/AnnouncementManager.php b/main/inc/lib/AnnouncementManager.php
index 3748621eaf..e964c5b2bf 100755
--- a/main/inc/lib/AnnouncementManager.php
+++ b/main/inc/lib/AnnouncementManager.php
@@ -719,9 +719,9 @@ class AnnouncementManager
 
         // the buttons for adding or removing groups/users
         echo '<td valign="middle">';
-        echo '<button class="arrowr" type="button" onClick="javascript: move(this.form.elements[1], this.form.elements[4])" onClick="javascript: move(this.form.elements[1], this.form.elements[4])"></button>';
+        echo '<button class="btn btn-default" type="button" onClick="javascript: move(this.form.elements[1], this.form.elements[4])" onClick="javascript: move(this.form.elements[1], this.form.elements[4])"><i class="fa fa-arrow-right"></i></button>';
         echo '<br /> <br />';
-        echo '<button class="arrowl" type="button" onClick="javascript: move(this.form.elements[4], this.form.elements[1])" onClick="javascript: move(this.form.elements[4], this.form.elements[1])"></button>';
+        echo '<button class="btn btn-default" type="button" onClick="javascript: move(this.form.elements[4], this.form.elements[1])" onClick="javascript: move(this.form.elements[4], this.form.elements[1])"><i class="fa fa-arrow-left"></i></button>';
         echo "</td>";
 
         echo "<td>";
@@ -754,9 +754,9 @@ class AnnouncementManager
 
         // the buttons for adding or removing groups/users
         echo "<td valign=\"middle\">";
-        echo '<button class="arrowr" type="button" onClick="javascript: move(this.form.elements[1], this.form.elements[4])" onClick="javascript: move(this.form.elements[1], this.form.elements[4])"></button>';
+        echo '<button class="btn btn-default" type="button" onClick="javascript: move(this.form.elements[1], this.form.elements[4])" onClick="javascript: move(this.form.elements[1], this.form.elements[4])"><i class="fa fa-arrow-right"></i></button>';
         echo '<br /> <br />';
-        echo '<button class="arrowl" type="button" onClick="javascript: move(this.form.elements[4], this.form.elements[1])" onClick="javascript: move(this.form.elements[4], this.form.elements[1])"></button>';
+        echo '<button class="btn btn-default" type="button" onClick="javascript: move(this.form.elements[4], this.form.elements[1])" onClick="javascript: move(this.form.elements[4], this.form.elements[1])"><i class="fa fa-arrow-left"></i></button>';
         echo "</td>";
         echo "<td>";
 
diff --git a/main/social/group_invitation.php b/main/social/group_invitation.php
index c67a2e359b..e2bbaac7a5 100755
--- a/main/social/group_invitation.php
+++ b/main/social/group_invitation.php
@@ -446,11 +446,11 @@ $form .= '</div>';
 $form .= '</td><td width="10%" valign="middle" align="center">';
 
 if ($ajax_search) {
-    $form .= '<button class="arrowl" type="button" onclick="remove_item(document.getElementById(\'destination_users\'))" ></button>';
+    $form .= '<button class="btn btn-default" type="button" onclick="remove_item(document.getElementById(\'destination_users\'))" ><i class="fa fa-arrow-right"></i></button>';
 } else {
-    $form .= '<button class="arrowr" type="button" onclick="moveItem(document.getElementById(\'origin_users\'), document.getElementById(\'destination_users\'))" ></button>
+    $form .= '<button class="btn btn-default" type="button" onclick="moveItem(document.getElementById(\'origin_users\'), document.getElementById(\'destination_users\'))" ><i class="fa fa-arrow-left"></i></button>
     <br /><br />
-    <button class="arrowl" type="button" onclick="moveItem(document.getElementById(\'destination_users\'), document.getElementById(\'origin_users\'))" ></button>
+    <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById(\'destination_users\'), document.getElementById(\'origin_users\'))" ><i class="fa fa-arrow-right"></i></button>
     <br /><br />';
 }
 
@@ -470,7 +470,7 @@ $form .= '</select></td>
 <tr>
 	<td colspan="3" align="center">
 		<br />
-		<button class="save" type="button" value="" onclick="valide()" >' . get_lang(
+		<button class="btn btn-primary" type="button" value="" onclick="valide()" >' . get_lang(
         'InviteUsersToGroup'
     ) . '</button>
 	</td>
diff --git a/main/user/add_users_to_session.php b/main/user/add_users_to_session.php
index 9125d68c3d..e511cee49b 100755
--- a/main/user/add_users_to_session.php
+++ b/main/user/add_users_to_session.php
@@ -515,13 +515,17 @@ if($_configuration['allow_tutors_to_assign_students_to_session'] == 'true') {
             <?php
                 if ($ajax_search) {
                 ?>
-                  <button class="arrowl" type="button" onclick="remove_item(document.getElementById('destination_users'))" ></button>
+                  <button class="btn btn-default" type="button" onclick="remove_item(document.getElementById('destination_users'))" ><i class="fa fa-arrow-left"></i></button>
                 <?php
             } else {
                 ?>
-                    <button class="arrowr" type="button" onclick="moveItem(document.getElementById('origin_users'), document.getElementById('destination_users'))" onclick="moveItem(document.getElementById('origin_users'), document.getElementById('destination_users'))"></button>
+                    <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('origin_users'), document.getElementById('destination_users'))" onclick="moveItem(document.getElementById('origin_users'), document.getElementById('destination_users'))">
+                        <i class="fa fa-arrow-right"></i>
+                    </button>
                     <br /><br />
-                    <button class="arrowl" type="button" onclick="moveItem(document.getElementById('destination_users'), document.getElementById('origin_users'))" onclick="moveItem(document.getElementById('destination_users'), document.getElementById('origin_users'))"></button>
+                    <button class="btn btn-default" type="button" onclick="moveItem(document.getElementById('destination_users'), document.getElementById('origin_users'))" onclick="moveItem(document.getElementById('destination_users'), document.getElementById('origin_users'))">
+                        <i class="fa fa-arrow-left"></i>
+                    </button>
     
                   <?php
                 }
@@ -531,7 +535,7 @@ if($_configuration['allow_tutors_to_assign_students_to_session'] == 'true') {
             <br />
     		<?php
     		if (isset($_GET['add'])) {
-    			echo '<button class="save" type="button" value="" onclick="valide()" >'.get_lang('FinishSessionCreation').'</button>';
+    			echo '<button class="btn btn-primary" type="button" value="" onclick="valide()" >'.get_lang('FinishSessionCreation').'</button>';
             } else {
                 //@todo see that the call to "valide()" doesn't duplicate the onsubmit of the form (necessary to avoid delete on "enter" key pressed)
     			echo '<button class="save" type="button" value="" onclick="valide()" >'.get_lang('SubscribeUsersToSession').'</button>';