BuddyPress.org

I add this to the css of my theme :

#content-sidebar {
float: left;
width: 100%;
-moz-border-radius-topleft: 6px;
-webkit-border-top-left-radius: 6px;
-moz-border-radius-bottomleft: 6px;
-webkit-border-bottom-left-radius: 6px;
}

#content-sidebar .padder {
margin-right: 350px;
border-right: 0px solid #ddd;
-moz-border-radius-topleft: 6px;
-webkit-border-top-left-radius: 6px;
-moz-border-radius-bottomleft: 6px;
-webkit-border-bottom-left-radius: 6px;
}

and i call