A big part of the Wordpress theme development process is to asses what each possible HTML element will look like (images, tables, lists, paragraphs, etc). WPCandy.com has the right sample content for that.
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How to center divs within a page with CSS
Sometimes you may want to center a div element within a page, whether vertically, horizontally, or both (dead center). Here’s how you can accomplish all of that using CSS.