Scoped CSS Screenshot from CanIUse.com Service Portal as a Content Management System has introduced something that now seems like an obvious oversight in all other CMS applications. In fact, its such a obvious, painful oversight that countless others have attempted some sort of solution. CSS Preprocessors, the HTML5 spec, and the recent CSS and JS specs all introduced scoped concepts such as a scoped attribute, scope pseudo selector, and scoping capability with Shadow DOM most of which was promptly ignored by browsers and removed from spec.