Narrow right column

You have to make adjustments in your theme’s styles.css file. Each theme is different, but often the section for the sidebar will be called #sidebar Try adjusting the width setting. Again, each theme is coded in different ways so no guarantee that alone will achieve what you want. You may have to adjust other settings also.

Its always advised before messing with your stylesheet, to make a backup copy so you can go back to how it is now.