Here is a collection of some tips and tricks we've learnt by using CCSS in production.
A common case is shorthands where you still want to be able to use number conversion and/or resolve mapped values:
border: '1px solid #000'
If you're passing an array value, CCSS will loop through each value, try to resolve, and concat.
This also works while resolving value maps, eg. using custom colors:
border: [1, 'solid', 'dark']