bbp-form style

Hi.
Im using motoblog theme from wolfthemes. After installing bbPress forum plugin i had issue with content wrapper. In the custom css section added fief lines:

#bbpress-forums {
    width: 92%;
    max-width: 1140px;
    margin: 0 auto 30px;

}

But i still have the problem with bbp-forum section image: http://imgur.com/2cGasYv
Can someone please help me with this problem? I zoomed out page to create image.