width and extra position

Hi there

Template:
t3_bs3_blank
Layout:
Home-2

1) Im looking for at way to make the default width of the right column 33% in staid of 25% and at the same time make the main-content 67% in staid of 75%. Both in big screen mode.
I tried to fix this with a custom.css, but it backfires on smaller screens.

css example:

.col-md-3 {
min-width:33%;
}

.col-md-9 {
max-width: 67%;
}

I can seem to find the Less file to make the prober fix.

2) I also need to add an extra position under the main content that uses the same css-style as the maincontent and keeps the right column on its right side.

Thank you for giving me a hand and thanks for a great framework.

MIkkel