Help with background command

Hi all, it’s been along time since i used CSS, but i am using again for a project, this is so basic, but can’t remember.

I have a background image that i want to stretch across the browser window, but none of the commands in Dreamweaver do what i want, here’s the code:

margin: 0;
padding: 0;
font-family: arial, helvetica, geneva, verdana, sans-serif;
font-size: 62.5%;
color: #636363;
background: #fff url(…/images/beach-background.jpg) repeat; /* Background wash */
text-align: justify;

It’s on repeat by default, if i choose center it puts the image in the center and repeats again behind???

This is an example of what i want to achieve - http://www.bmstravel.com/

Any help much appreciated