I was reading an article on the internet and have been using tables design my websites.

However this article advises not to use them. http://webdesign.about.com/od/layout/a/aa111102a.htm ( one of the reasons being, it doesnt support good SEO )

So how do I create a section such as A BOX WITH ROUNDED EDGES ??? e.g. this forums, are enclosed in a box/table like with rounded well formatted edges

In the past I used to add a table/table(s) and format it with css such as

width: 98%;
background-color: #FFFFFF;
margin: 20px auto 0px auto;
border: 1px solid #000066;
border-radius: 8px 8px 8px 8px;
vertical-align: 95%;
height: 90%;

But without tables, how do i achieve this ?

many thanks