Some like Magic User Interface for the Amiga, but across Operating Systems, and which provides the resulting stylesheet to the browser (with no ability for site

Some like Magic User Interface for the Amiga, but across Operating Systems, and which provides the resulting stylesheet to the browser (with no ability for sites to override it unless I allow it) would be my dream and a marketers nightmare. Just information and media, displayed how each person prefers them to be displayed (and obviously with a lot of user made themes for people to browse and try out). With sub-configs like super-compact, whimsical etc. that users can apply to individual apps and sites.