Reply To: Changing column width

If you search for this in your css (around line 888) –

.sidebar-secondary {
    float: left;
    width: 180px;
}

That is how you can adjust the left sidebar.

To adjust the main content area look for this in your css (around line 864) –

.content-sidebar-sidebar .content,
.sidebar-content-sidebar .content,
.sidebar-sidebar-content .content {
	width: 520px;
}