CSS has always been contextual,
with a Cascade & Normal Flow
that allow content & styles to adapt across browsers,
writing modes, device interfaces,
and user-defined preferences.
(part of the initial language proposal!)
kicked off a decade of Responsive Web Design –
with more explicit control for
adapting designs to different context.
there’s only one global context shared by every element on the page.
Container Queries are here to change that. We can define ‘containers’ that expose more localized context – and then query those containers in a variety of ways. Beyond just the highly anticipated size queries, we also get new container-relative units, and a road-map for querying container styles, states, and more.