Mailgraph contains a stylesheet inside the mailgraph.cgi perl script. But it would be much more convenient if the stylesheet would be external, and specific to one webapp installation.
I made a patch against mailgraph.cgi which removes the CSS code and instead links in an external stylesheet (mailgraph.css) which has to be in the MY_HTDOCSDIR. The patched ebuild copies over a default mailgraph.css which contains exactly the CSS that was in mailgraph.cgi before. Thus the default appearance of Mailgraph (as intended by the author) isn't being changed, but changing it by the user is now much easier. The user can now just copy his own CSS file over mailgraph.css or modify it.
Created attachment 120240 [details, diff]
Patch against mailgraph-1.13.ebuild
I hope I did that right...
Created attachment 120241 [details]
CSS extracted from mailgraph.cgi and stored in separate file
Created attachment 120242 [details, diff]
mailgraph-external-css.patch (which will be applied against mailgraph.cgi by the patched ebuild)
You should send this upstream, this is not a Gentoo-specific issue at all.
Ok, I sent a suggestion upstream...