- border, border-collapse, border-width
- box-sizing
- float
- font, font-family, font-size, font-weight, line-height
- height
- letter-spacing
- margin
- max-height
tl;dr Developers would like the idea to style components based on a parent's width rather than depend solely on the viewport media query. This would allow modular components to style themselves while being agnostic to the viewport.
There is currently a lot of developer interest in getting a feature like Container Queries (née "Element Queryies") shipped in a browser.
Here are official'ish documents to outline the developer community's desires.