Question

I am styling a web application that I made with Java EE (using JSF and Primefaces) and I want to override the styling Primefaces gives to the components. Is it possible to set a whole stylesheet to be preferred? Like saying the whole document to be “important”?

Answer 1

If you can have your CSS declared after the Primefaces CSS, your CSS will take precedence.

Taken from the CSS spec:

6.4.1 Cascading order

To find the value for an element/property combination, user agents must apply the following sorting order:

Find all declarations that apply to the element and property in question, for the target media type. Declarations apply if the associated selector matches the element in question and the target medium matches the media list on all @media rules containing the declaration and on all links on the path through which the style sheet was reached.
Sort according to importance (normal or important) and origin (author, user, or user agent). In ascending order of precedence:

  1 user agent declarations  
  2 user normal declarations  
  3 author normal declarations  
  4 author important declarations  
  5 user important declarations   

Sort rules with the same importance and origin by specificity of selector: more specific selectors will override more general ones. Pseudo-elements and pseudo-classes are counted as normal elements and classes, respectively.

Finally, sort by order specified: if two declarations have the same weight, origin and specificity, the latter specified wins. Declarations in imported style sheets are considered to be before any declarations in the style sheet itself.

Otherwise, no, you’ll have to mark each element as !important I’m afraid.