Please do not use this issue tracker for support requests. Only for bug reports and feature requests. Regarding your question, the colours in the Web-UI can be changed in src/http/cervlet.c and recompile
sorry, for me it's a new feature request to load a customized CSS…
I will not recompile the software just to change a color! It would be ridiculous.
If my request of evolution can not be taken into account for a future version it is a pity ...