> cover fills the entire width and height of the node.
Does that work like the CSS background-size: cover; or background-size: 100% 100%;?
> ratio maintains the aspect ratio of the background image.
Does that mean CSS cover? contain? Something else?
Colors can be specified in hex format, e.g. "#FFFFFF". Six preset colors exist, mapped to the following numbers:
1 red
2 orange
3 yellow
4 green
5 cyan
6 purple
Maybe the file format isn't meant to reproduce the exact same look in different software, but merely communicate user intent. Your guess is as good as mine.