I have v6, how can I change the font type in site title?
It would be the same as Serenity. Make a clone of the theme before making any changes or you can have issues with upgrades. Once you make a clone, you can then edit the Theme.css in the admin panel. Tutorials are in our Learning Center.
https://community.socialengine.com/blogs/597/62/theme-editor
This one is for Serenity (v5) but it is almost the same for Elpis. I haven't finished bringing that tutorial over. When I am working Monday, I'll have it done.
https://community.socialengine.com/blogs/597/70/serenity-theme
hopefully the above will help