class is used in most of the Kendo widgets. In is present in all drop-downs and also in all complex widgets, that contain drop-downs. Therefore, using that class for applying custom styles on the Notification may cause considerable styling issues.
What I would recommend you to use instead is the custom class, that is appended to the <div> element of each Notification widget . You could get that class name from the instance of the widget:
The following Dojo
customClass = centered._guid;
demonstrates how to get the above class and inject a style rule, that would affect only that Notification widget element.
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