1) If you want to use a CSS preprocessor with a custom build it's a fairly DIY process, meaning you should write another build step just for that task. You have to run the preprocessor prior to the other build steps so ngc can build with the compiled css for production.
concatMap( results => postCSS(options, context) ),
concatMap( results => ngc(options, context) ),
concatMap( results => closure(options, context) )
While the angular-rollup project doesn't conform to the Architect CLI yet, there are examples of how to use PostCSS and SASS respective API programmatically here. What I've done in the past is copy the src directory to a temporary directory, then run the css preprocessor, and then compile AOT for production. The compiler takes care of inlining the css in the AOT compiled code. It will inline whatever is in the css file each component is pointing to, minified or not.
We're a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.