Liferay minifies the css files and renders as one single main.css file. This improves the performance in production. However, while developing a theme a css specialist would want that liferay does not minify and club all the css files into one single main.css. This tutorials explains the entire concept surrounding css minification.
Friendly URLs are easy. But when the parameter values are not know at the time of loading the page and is expected to be provided by the end user then how do you get the friendly url working. I know the trick !