Angular: Empty Fiddle
http://angularjs.org/
HTML
<script src="http://code.angularjs.org/angular-1.0.1.js"></script>
<div ng-controller="MyCtrl">
var1 = {{var1}}, var2 = {{var2}}
<div ng-class="{'red': (var1 && var2)}">
Hello!
</div>
</div>
CSS
.red {
background: red;
}
JavaScript
var myApp = angular.module('myApp',[]);
//myApp.directive('myDirective', function() {});
//myApp.factory('myService', function() {});
function MyCtrl($scope) {
$scope.var1 = true;
$scope.var2 = true;
}