Simple Machines Community Forum

I would like to change the size of the font for topic headers. To avoid confusion I have added an image and circled the part in question.

In the index.css file this is the section that changes that.
/* Styles for rounded headers.
------------------------------------------------------- */
h3.catbg, h3.catbg2, h3.titlebg, h4.titlebg, h4.catbg
{
    overflow: hidden;
    height: 31px;
    line-height: 31px;
    font-size: 1.3em;
    font-weight: bold;
}

It modifies all text in that header part though.