l1 l2 l3 l4 l5 l6 l7 l8 l9 l10
c1 c2 c3 c4 c5 c6 c7 c8 c9 c10.

For the center part to work, you must put in margins that force it out of the #left and #right areas.

That included the margins of those areas along with the text display areas.

If you don't put in these margins the center region will overlap the #left and #right areas.