Revert "Update nav.html"

This reverts commit 3d0256f65cdc2141bbd8c499a11a6e39c3bf88a1.
Revert "maybe cosmo instead"

This reverts commit 334f7eb31a6a890e34fa8b19d32ce3fbbbec7ecc.
Revert "bootswatch cyborg :-)"

This reverts commit 44ead7ecffa10502d8eb8c4aff2cffe9258cffd5.