+container // header and footer are full-width by default. header, footer clear: both // nav spans 3 columns of total 12. nav +span-columns(3,12) .content // content spans the final (omega) 9 columns of 12. +span-columns(9 omega,12) // main content spans 6 of those 9 columns. .main +span-columns(6,9) // secondary content spans the final 3 (omega) of 9 columns. .secondary +span-columns(3 omega,9) • • • • • • •