CSS cascade / origin / layer / specificity
Do not decide a winner from specificity alone. Review origin, layer, source order and important separately with synthetic rules and no external stylesheet fetch.
Separate origin and importance, layer, specificity and source order to avoid adding unnecessary important declarations.
origin → layer → specificity → source order
!important is a separate boundary from ordinary rules| Axis | Review |
|---|---|
| origin | Do not mix author, user and UA origin. |
| layer | Separate layer order from unlayered rules. |
| specificity | Use it as a comparison within the same conditions. |
| source order | Check later order when other conditions match. |
| important | Review origin and layer before adding it. |
This page does not load an external stylesheet. Apply real CSS changes only through the existing review process.
| case | result |
|---|---|
origin-author | Author origin |
layer-order | Layer order |
specificity | Specificity |
source-order | Source order |
important-override | Important boundary |
unsupported-external-css | Reject |