22. Specifying the type of counter created by list-style-type

A CSS rule such as:

ol[type="I"] {
    list-style-type: upper-roman;
}

implicitly creates a counter, but does not allow to give it a name or to parameterize it in any way.

Extension property list-item-counter may be used to specify the counter implicitly created by list-style-type. Example:

ol > li {
    list-item-counter: counter(list-item) ". ";
    counter-increment: list-item;
}