[Spec] 4.5 Reading System Overrides

[JayPanoz]

While implementing Readium CSS, I came across “4.5 Reading System Overrides”, especially the following:

the getOverrideStyle method [DOM2 Style]

There is currently an open issue about override declarations on CSSWG-draft. Apparently, it’s never been implemented and is very likely to be dropped in CSS Cascade.

[JayPanoz]

I was also wondering if an explicit link to CSS Cascading and Inheritance Level 3 would be useful as the order is way more complex than authors usually expect.

1. Transition declarations [CSS3-TRANSITIONS]
2. Important user agent declarations
3. Important user declarations
4. Important override declarations [DOM-LEVEL-2-STYLE]
5. Important author declarations
6. Animation declarations [CSS3-ANIMATIONS]
7. Normal override declarations [DOM-LEVEL-2-STYLE]
8. Normal author declarations
9. Normal user declarations
10. Normal user agent declarations

Indeed, !important completely changes the order or priority.