Location of Theme files on Linux

[seth.feinberg]

I'm sorry that this is such a noobish question but what is the location of the Theme files in the Linux file hierarchy? I saw a brief snippet in the installation page that mentioned some files in /etc/default, but my Linux box (A Synology) doesn't have a /etc/default, just a /etc/defaults/ and just a rc.conf file in there. I found a number of files and folders in /volume1/@appstore/Subsonic but nothing that appeared to contain the themes. Can anybody shed some light on this for me please?