CCCCCc1c2nc(c(CCCCC)c3ccc([nH]3)c(CCCCC)c3nc(c(CCCCC)c4ccc1[nH]4)C=C3)C=C2
A rotatable bond is defined as any single non-ring bond, attached to a non-terminal, non-hydrogen atom. How many bonds in the molecule are rotatable?