1. CSS Cascade Layers

    The `@layer` at-rule allows authors to explicitly layer their styles in the cascade, before specificity and order of appearance are considered.

  2. cssimportrule api: layername

  3. csslayerblockrule api

  4. csslayerblockrule api: name

  5. csslayerstatementrule api

  6. csslayerstatementrule api: namelist

  7. css at-rule: `@import`: `layer()`

  8. css at-rule: `@layer`

  9. css selector: `:active`: observes top-layer ancestor matching boundary behavior

  10. css selector: `:focus-within`: observes top-layer ancestor matching boundary behavior

  11. css selector: `:hover`: observes top-layer ancestor matching boundary behavior

  12. types: global keywords: revert-layer