Messy thame

Gosh! You’ve made a mess of that! But try this:

#bb_right .bbr_box {
  width: 240px;
}

You can either alter it directly in the style sheet (line 369 and following) if you must, or you can add this as a new rule at the bottom of the style sheet.

The best thing to do would be to create a child theme, but I guess it may be too late for that now.

HTH

PAE