CSS counters are, in essence, variables maintained by CSS whose values may be incremented by CSS rules to track how many times they're used. This lets you adjust the appearance of content based on its placement in the document. CSS counters are an implementation of Automatic counters and numbering in CSS 2.1.
 Though value can be set, any modifications happening while there are automation events scheduled — that is, events scheduled using the methods of the AudioParam — are ignored, without raising any exception.