I must first confess that I am a beginner at web design but whenever I design my divs never sit flush against the browser window. What styles should I use?

Actually this is not your fault pal, Some browser doesn't support some of the features of HTML or any designing coding. If you want to see the effects then you have to consider all the browser and make your code. At the same time you also have to check the syntax of your coding because single spelling mistakes also can create the problem to whole designing.

I must first confess that I am a beginner at web design but whenever I design my divs never sit flush against the browser window. What styles should I use?

 

Do you have a browser reset stylesheet?

CSS reset...

 

http://meyerweb.com/eric/tools/css/reset/

in the css do this

 

body{
  top:0px;
  margin:0px;
}

 

This will make it site flush to the top

 

Hope this helps