@ngdoc overview @name Templates: Working With CSS in Angular @description Angular sets these CSS classes. It is up to your application to provide useful styling. # CSS classes used by angular * `ng-scope` - **Usage:** angular applies this class to any element that where a new {@link ng.$rootScope.Scope scope} is defined. (see {@link guide/scope scope} guide for more information about scopes) * `ng-binding` - **Usage:** angular applies this class to any element that is attached to a data binding, via `ng-bind` or `{{}}` curly braces, for example. (see {@link guide/databinding databinding} guide) * `ng-invalid`, `ng-valid` - **Usage:** angular applies this class to an input widget element if that element's input does not pass validation. (see {@link ng.directive:input input} directive) * `ng-pristine`, `ng-dirty` - **Usage:** angular {@link ng.directive:input input} directive applies `ng-pristine` class to a new input widget element which did not have user interaction. Once the user interacts with the input widget the class is changed to `ng-dirty`. ## Related Topics * {@link guide/templates Angular Templates} * {@link guide/forms Angular Forms}