Remove "Padding" From Twenty-Eleven Template

I have been trying to do this for two entire days now with no luck.

My website is http://www.thewineymom.com

Basically, I want the area that is gray half of what it is now (on the sides) and completely gone from the top margin (above the header). I will eventually change the gray to white, but just have it there now for a visual.

I don’t know if I’m supposed to be removing padding or changing the widths of the post body & sidebar.

I have already created a child theme and I have tried inspecting the elements with firebug and still can’t seem to find the source that needs adjusted.

Feeling clueless at this point, please bare with me!