For others reading this thread, this question was answered in another thread. For information purposes, this was the relevant part of the response:
Centering is a bit tricky with CSS.
There are multiple ways to accomplish it, but I think the simplest is to do the following:
div.TT_wrapper{ background-color: #FFF; width: 25%; margin-left: auto; margin-right: auto; }
div.TT_wrapper div.TT_Text{ font-size: 18pt; }
Notice the addition of the margin entries in the div.TT_wrapper line. In CSS, margins are the space around the outside of the element. So, it is surrounding the div.TT_wrapper. The default margin for <div> elements is 0, or, in other words, no margin. So, when you give the <div> a width, it aligns to the left since there’s nothing pushing it to the middle, and it can’t fill the whole space. By specifying margins of auto for the left and right, the web browser is then forced to make the left and right margins equal in size. Yielding a centered <div>.
I hope this has helped.
