The priority of the rules depends on their relative specificity. Specificity is computed
as three numbers, a-b-c (in
a number system with a large base). The number of ID building blocks
in the selector gives the first number a,
the number of classes, pseudo-classes and attributes gives b,
and the number of element types gives c.
The examples in the following table are in priority order,
with the most specific first.
Priority Order Example
| Selector |
Specificity |
| #title > #author.full |
“2-1-0” |
| #title |
“1-0-0” |
| P.intro P.citation |
“0-2-2” |
| UL OL LI.red |
“0-1-3” |
When two rules give the same specificity number, the
order of appearance gives the priority (the last seen overrides previous
rules).
Priority is used as follows: first the declarations of
all rules that match the same objects are merged, and then the priority
is applied only if there is a conflict (same key value) within the
merged declaration block.