I don't do this for a living, and am just trying to get my own stuff sorted, so please excuse me if I'm asking dumb questions. Thanks.

Trying to better understand responsive design, I'm experimenting with a tutorial from http://www.netmagazine.com/tutorials...-site-css#null.

I notice that after increasing the body front size, when reducing the browser window to see the reflow, unwanted vertical space appears between the logo and the nav.

Here's a screenshot of 3 browser windows, the second of which shows the unwanted space:


Why is this and what's the fix?