For me it was understanding the differences between creating output by digging down from a root or by transforming a document by matching parts of it and lettin

For me it was understanding the differences between creating output by digging down from a root or by transforming a document by matching parts of it and letting the default rules handle the rest. Which is the basis of my stylesheet that turns an HTML file into its own formatted and highlighted source code: https://gist.github.com/spiralx/dcb7e5fa4e5dedd800e292848ed22aa9 https://gist.github.com/spiralx/dcb7e5fa4e5dedd800e292848ed2...