в ББ-коды добавить не могу, поэтому сюда
bbcode tag = frbox
html replacement =
<div class="frbox">{text}</div>
css in extra/less: (change to suit)
CSS:
.frbox
{width:240px;
/* or you might want max-width*/
float:right;
margin-left:20px;
padding:10px;
background:#f1f1f1;
border-radius:15px}
@media (max-width: @xf-responsiveMedium)
{.frbox
{width:100%;
float:none;
margin-left:0px}
}