This CSS should do it.
Thank you, will try it.
But why? What's the size of your notebook screen? Can't you upgrade to other browsers like Google Chrome?
Here is a screenshot
of JGO from notebook. And I have to use such large fonts because of problems with my eyes. With fonts of this size some sites have horizontal scrolling and Opera 12 has a feature "Fit To Width" which allows to reflow text and get rid of horizontal scrolling.
But Opera 12 is almost abandonware so periodically I try to switch to Chrome or Firefox. But still feel uncomfortable with them...