server/core/css/multiselect.css

/* Copyright (c) 2011, Jan-Christoph Borchardt, http://jancborchardt.net
 This file is licensed under the Affero General Public License version 3 or later.
 See the COPYING-README file. */

 ul.multiselectoptions {
 	background-color:#fff;
 	border:1px solid #ddd;
 	border-top:none;
 	box-shadow:0 1px 1px #ddd;
 	padding-top:.5em;
 	position:absolute;
	max-height: 20em;
	overflow-y: auto;
 	z-index:49;
 }

 ul.multiselectoptions.down {
 	border-bottom-left-radius:.5em;
 	border-bottom-right-radius:.5em;
 }

 ul.multiselectoptions.up {
 	border-top-left-radius:.5em;
 	border-top-right-radius:.5em;
 }

 ul.multiselectoptions>li {
 	overflow:hidden;
 	white-space:nowrap;
 }

 ul.multiselectoptions>li>label {
	margin-left: 5px;
 }

 div.multiselect {
 	display:inline-block;
 	max-width:400px;
 	min-width:100px;
 	padding-right:.6em;
 	position:relative;
 	vertical-align:bottom;
 }

 div.multiselect.active {
 	background-color:#fff;
 	position:relative;
 	z-index:50;
 }

 div.multiselect.up {
 	border-top:0 none;
 	border-top-left-radius:0;
 	border-top-right-radius:0;
 }

 div.multiselect.down {
 	border-bottom:none;
 	border-bottom-left-radius:0;
 	border-bottom-right-radius:0;
 }

 div.multiselect>span:first-child {
 	float:left;
 	margin-right:2em;
 	overflow:hidden;
 	text-overflow:ellipsis;
 	width:90%;
 }

 div.multiselect>span:last-child {
 	position:absolute;
 	right:.8em;
 }

 ul.multiselectoptions input.new {
 	border-top-left-radius:0;
 	border-top-right-radius:0;
 	padding-bottom:.2em;
 	padding-top:.2em;
 	margin:0;
 }