OpenCart Community

Hi, guys!
I dont want use any additional module or themplate, but want to personalize my Homepage header.
I hope somebody could help me.

1. I want to "extend" main menu bar and slider, like on the adjusted image.
You see the right side? This is a default theme with margin.
I want it be as on the left side of the image.
I know the header is not inside wrapper that limited to 1140 pixel wide, so it is possible to extend it.
But where and how?
http://data.awardspace.com/website_header.jpg

2. The mobile version of the main menu appears if @media (max-width: 767px)
I have a "logn" menu so I want it be mobile from 900px, I change the .css code but nothing happens.
Where should I also edit to make it work?

@media (min-width: 901px) {
#menu .dropdown:hover .dropdown-menu {
display: block;
}
}
@media (max-width: 900px) {
#menu {
border-radius: 4px;
}
... more code...
}

Thanks