Greetings,
I used your first fix and it worked perfectly but then I modified it to minimize the width of the primary sidebar to 200px from 260px:
.col-3cm .main-inner { padding-left: 200px; background-position: -140px 0; }
.col-3cm .s1 { margin-left: -200px; }
.s1 { width: 200px; }
@media only screen and (min-width: 479px) and (max-width: 960px) {
.s1-expand .s1 { width: 200px; }
.s1-expand .s1 .sidebar-content,
.s1-expand .s1 .post-nav { min-width: 200px; }
then I minimized the Website Max-width to minimum ( 1024px ) from the Theme Option and fixed the secondary sidebar to 200px width too:
.col-3cm .s2 { float: right; margin-right: -260px; /* ingenuity! */ position: relative; right: -100%; width: 200px;}
And here I am with another empty space but this time its between the content and the secondary sidebar..How to expand it ?