Vega lite - Labels and background colour

[GeorgeRobbin]

1 - Im attempting to create a chart which displays 4 sections based on values on each axis (-x,-y)(-x,y)(-y,x)(xy), is there a way to set a separate background colour for each section?
2 - is there a way to add a permanent label to specific data points (text function i believe)
HOUSE_MORTGAGE.json

[jwoLondon]

The key here is to use layers – one for your background quadrants, one for the dots and one for the labels. Here's one approach that uses the rect mark to draw the quadrants each with a custom colour determined by inline data.