I looked at your CSS and your index.html. I found some things. First, The wrapper element should be before the header element. I didn't see a closing tag for the wrapper. I like to add a comments to my closing div's that way I know what it's closing. When you get a lot of text and code between the opening and closing div's it can be confusing. A comment for html is different than CSS. <!-- closes the wrapper --> The browser doesn't display it. Give the wrapper a % for the width and auto for the margin. The auto will center the wrapper.

wrapper {

width: 90%;
margin: auto;
height: auto; 

}

In the nav you don't need the class="selected" in the li item. Are you trying to style the links for visited, hover etc?

You shouldn't need to float the header left. I like to give each different section a solid border and different color while I'm designing. It helps me see what going on. You can delete the borders when you are done. Like header { border: solid black; } nav { border: solid red; }

Start with those suggestions and see what happens.

Vicki