Reply To: How do I change widths of sidebars and main content area

It seems that you are familiar with CSS. Please add the below CSS codes and maintain width with the help of commented info there.

//left sidebar and main content area width
.both-sidebar #primary-wrap {
    float: left;
    width: 76%;
}

//main content area width
.both-sidebar #primary-wrap #primary {
    float: right;
    width: 70%;
}

//left sidebar width
.both-sidebar #primary-wrap #secondary-left {
    float: left;
    width: 30%;
}

//right sidebar width
.both-sidebar #secondary-right {
    float: right;
    width: 24%;
}

If the design will not as good as you want, you can change the width % above and maintain the width.
Hope, this will solve the issues.

Warm Regards
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