[Mapcss] Bug in the mapcss introduction slieds of Maskim?

[Peter Wendorff]

Hi.
I have to give a short introduction to someone who should implement a 
mapcss renderer and looked into the docs availlable for that.
For that I especially looked into the sotm-eu presentation done by 
Maskim [1], and I fear there is a small bug on slide 7 (and the 
following pages).

The stylesheet presented does not contain any z-index or layer 
definitions. To quote the slide, it's defined as:

line[highway] {
     color: orange;
     width: 11;
}

area[building] {
     fill-color: gray;
}

line[waterway] {
     color: blue;
     width:3;
}

The image presented nearby shows a similar image, but the highway is 
rendered on top of the river.
Shouldn't that be the other way around (according to the mapcss code, 
not to "good maps")?

regards
Peter

[1] http://sotm-eu.org/slides/10_MaksimGurtovenko_MapCSS.pdf