Consider adding support for CSS breakpoing / media queries in ThemeBuilder.
https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_media_queries/Using_media_queries
https://www.w3schools.com/howto/howto_css_media_query_breakpoints.asp
This will enable users to create response design directly within the ThemeBuilder application.
Requested through t.1682156