diff --git a/app/views/archetype.html b/app/views/archetype.html
index d86f456..13238df 100644
--- a/app/views/archetype.html
+++ b/app/views/archetype.html
@@ -2,7 +2,7 @@
     <textarea class="archetypeDeveloperModel" ng-show="model.config.developerMode" ng-model="model.value"></textarea>
     <ul ui-sortable="sortableOptions" ng-model="model.value.fieldsets" ng-show="!showAddButton()">
         <li ng-repeat="fieldset in model.value.fieldsets">
-            <fieldset class="ng-class:fieldset.alias" ng-class="{archetypeFieldsetError: !fieldset.isValid}" ng-init="fieldsetConfigModel = getConfigFieldsetByAlias(fieldset.alias)">
+            <fieldset ng-class="[fieldset.alias, (!fieldset.isValid ? 'archetypeFieldsetError' : '')]" ng-init="fieldsetConfigModel = getConfigFieldsetByAlias(fieldset.alias)">
                 <div class="archetypeFieldsetLabel" ng-class="{enableCollapsing: model.config.enableCollapsing}">
                     <div ng-click="focusFieldset(fieldset)" class="label-sub module-label">
                         <span class="caret" ng-hide="fieldset.collapse || !model.config.enableCollapsing"></span>
@@ -28,7 +28,7 @@
                 </div>
                 <div class="archetypeCollapser animate-hide" ng-hide="isCollapsed(fieldset)">
                     <form class="form-inline">
-                        <div ng-class="{archetypePropertyError: getPropertyValidity($parent.$index, property.alias) === false}" class="archetypeProperty control-group ng-class:property.alias" ng-repeat="property in fieldsetConfigModel.properties">
+                        <div ng-class="[property.alias, (getPropertyValidity($parent.$index, property.alias) === false ? 'archetypePropertyError' : '')]" class="archetypeProperty control-group" ng-repeat="property in fieldsetConfigModel.properties">
                             <label ng-hide="archetypeConfig.hidePropertyLabels == '1'" class="control-label" for="archetype-property-{{model.alias}}-{{$parent.$index}}-{{$index}}">
                                 <span>{{property.label}}</span>
                                 <div class="archetypeFieldsetHelpText" ng-show="property.helpText">