diff --git a/modoboa/extensions/sievefilters/templates/sievefilters/index.html b/modoboa/extensions/sievefilters/templates/sievefilters/index.html
index 884040aa4..135647c1c 100644
--- a/modoboa/extensions/sievefilters/templates/sievefilters/index.html
+++ b/modoboa/extensions/sievefilters/templates/sievefilters/index.html
@@ -74,8 +74,8 @@ $(document).ready(function() {
 <div class="well sidebar-nav">
   <ul id="menu" class="nav nav-list">
     <li class="nav-header">{% trans "Filter sets" %}</li>
-    <li>
-      <select id="curfset" class="span12">
+    <li class="form-group">
+      <select id="curfset" class="col-sm-12 form-control">
         {% if active_script %}
         <option value="{{ active_script }}">{{ active_script }} ({% trans "active" %})</option>
         {% endif %}