My solution will help you to do that
+ Go to Admin site -> Extensions -> Template Manager -> JA_Portfolio – Default -> Layouts tabs -> main-right
From
<blocks name="middle" colwidth="20">
<block name="content-mass-top" style="raw">content-mass-top</block>
<block name="inset1" style="jaxhtml">left</block>
<block name="right1" style="jaxhtml">right</block>
</blocks>
Change to
<blocks name="middle" colwidth="30">
<block name="content-mass-top" style="raw">content-mass-top</block>
<block name="inset1" style="jaxhtml">left</block>
<block name="right1" style="jaxhtml">right</block>
</blocks>
Don’t forget to clear cache from Admin area after making changes