MediaWiki:Common.css
.addthis_toolbox {
background: #f5f5f5 !important;
border: 1px solid #ddd !important;
margin-bottom: 15px !important;
outline: 5px solid #eee !important;
}
.addthis_separator {
border-color: #ddd !important;
}
.portal {
background: #f5f5f5 !important;
border: 1px solid #ddd;
border-radius: 10px;
display: inline-block;
margin: 20px;
padding: 20px;
width: 40%;
}