try adding.
#rt-sidebar-a div.article_anywhere {
background-color: white;
border: solid 3px #db4448;
padding: 10px;
margin: -15px;
}
even if you would use a module-class, your css can't work because the color-codes are invalid CSS.
Please note that the RT-folks moved to the Gitter-chat. They don't look at this group anymore.