Improving CSS Architecture with Cascade Layers, Container Queries, Scope, by Miriam Suzanne
CSS is intentionally contextual, adapting to a range of user needs and interfaces – and the cascade makes that possible. But as the Web becomes more powerful, it’s clear that design engineers need more tools to organize and maintain larger code-bases across larger teams.
Cascade Layers will allow authors to manage their own internal cascade logic, without relying entirely on the specificity heuristic or source-order.
Container Queries will make it possible for individual elements to adapt based on more localized context, rather than relying on overall viewport dimensions.
Scope (still in the early design stage) will allow better targeting of selectors within a particular segment of the DOM, to help avoid naming conflicts across a larger project, or accidental overlap when nesting elements.