diff --git a/src/growlDirective.js b/src/growlDirective.js
index edad549..785db32 100644
--- a/src/growlDirective.js
+++ b/src/growlDirective.js
@@ -4,7 +4,7 @@ angular.module("angular-growl").directive("growl", ["$rootScope", function ($roo
 	return {
 		restrict: 'A',
 		template:   '<div class="growl">' +
-					'	<div class="growl-item alert" ng-repeat="message in messages" ng-class="computeClasses(message)">' +
+					'	<div ng-repeat="message in messages" ng-class="{{classes}}">' +
 					'		<button type="button" class="close" ng-click="deleteMessage(message)">&times;</button>' +
 					'       <div ng-switch="message.enableHtml">' +
 					'           <div ng-switch-when="true" ng-bind-html="message.text"></div>' +
@@ -18,7 +18,8 @@ angular.module("angular-growl").directive("growl", ["$rootScope", function ($roo
 			var onlyUnique = growl.onlyUnique();
 
 			$scope.messages = [];
-
+			$scope.classes = ['growl-item', 'alert'];
+			
 			function addMessage(message) {
 				$scope.messages.push(message);
 
@@ -30,6 +31,29 @@ angular.module("angular-growl").directive("growl", ["$rootScope", function ($roo
 			}
 			$rootScope.$on("growlMessage", function (event, message) {
 				var found;
+				
+				// Add classes based on message type
+				switch(message.severity){
+				case 'success':
+				    $scope.classes.push('alert-success');
+				    break;
+				case 'error':
+				    $scope.classes.push('alert-danger');
+				    break;
+				case 'info':
+				    $scope.classes.push('alert-info');
+				    break;
+				case 'warn':
+				    $scope.classes.push('alert-warning');
+				    break;
+				default:
+				    break;
+				}
+				
+				// Add any custom classes
+				if(message.classes)
+					$scope.classes.push(message.classes);
+
 				if (onlyUnique) {
 					angular.forEach($scope.messages, function(msg) {
 						if (message.text === msg.text && message.severity === msg.severity) {
@@ -52,16 +76,6 @@ angular.module("angular-growl").directive("growl", ["$rootScope", function ($roo
 				}
 
 			};
-
-			$scope.computeClasses = function (message) {
-				return {
-					'alert-success': message.severity === "success",
-					'alert-error': message.severity === "error", //bootstrap 2.3
-					'alert-danger': message.severity === "error", //bootstrap 3
-					'alert-info': message.severity === "info",
-					'alert-warning': message.severity === "warn" //bootstrap 3, no effect in bs 2.3
-				};
-			};
 		}]
 	};
 }]);