I'd like my website to have an header as wide as the user's screen, and the rest of the page not wider than a fixed value.
In "Settings -> Standard Layout -> Set a max width" I know I can set this on a general basis, but what's the cleanest way to do such a separation between header and rest of content in AT_Subtheme?
My guess is:
1) remove max width from theme settings
2) add max-width attribute to the container (#columns) below the header
3) add "margin: 0 auto;" to the #columns div to center it
But I'm asking because it's the first time i'm trying to do a responsive layout, and i'm afraid of screwing up the great job made by AT!