https://source.netsurf-browser.org/libdom.git/tree/src/core/...
https://source.netsurf-browser.org/libdom.git/tree/src/core/...
https://source.netsurf-browser.org/libcss.git/tree/src/parse...
Looks like the authors have a severe case of goto-phobia that causes a quadratic explosion of copy-pasted code in the error-return paths. Some of the files also feel like they have been translated into C from C++ or some other OO language by some automated tool, resulting in some very long "namespaced"-looking identifiers.
Then again, I don't think Firefox or WebKit code is that much better either, so my impression of this codebase is neither great nor horrible. As "beautiful" is subjective, to give a reference for what I'd consider beautiful, look at BSD or early UNIX.