Function timing_css_declarations 

pub fn timing_css_declarations() -> String

Emit the time axis as CSS declarations, no selector.

Intent::Debounce is emitted with the rest even though no stylesheet can use it. The point of the layer is that one document holds every duration in the system; a token that lives here for three of the four intents and in a JS constant for the fourth is the drift this crate exists to end, and a script can read the value back off the computed style.