silverstripe-framework/scss/TreeDropdownField.scss

div.TreeDropdownField {
	width: 400px;
	background: #fff;
	border: 1px solid #aaa;
	cursor: pointer;
	overflow: visible;
	position:relative;

	input {
		border: none;
		background: none;
		padding: 0;
		margin: 0;
	}
	
	.treedropdownfield-title {
		float: left;
		padding: 7px;
		width: 90%;
		line-height: 16px;
		overflow:hidden;
		outline: none;
	}

	.treedropdownfield-panel {
		clear: left;
		position: absolute;
		overflow: auto;
		display: none;
		cursor: default;
		border: 1px solid #aaa;
		border-top: none;
		margin: 1px 0 0 -1px; /* account for border on container div */
		max-height:200px;
		background-color: #fff;
		z-index: 50;
		-webkit-box-shadow: 0 4px 5px rgba(0,0,0,.15);
		-moz-box-shadow   : 0 4px 5px rgba(0,0,0,.15);
		-o-box-shadow     : 0 4px 5px rgba(0,0,0,.15);
		box-shadow        : 0 4px 5px rgba(0,0,0,.15);

		&.loading {
			min-height: 16px /* icon */ + 14px /* padding */; // Ensure there's room for loading indicator
			background: #fff url("../images/network-save.gif") 7px 7px no-repeat; 
		}

		ul.tree {
			margin: 0;

			a {
				font-size: 12px;
			}
		}
	}
		
	.treedropdownfield-toggle-panel-link {
		border: none;
		margin: 0;
		z-index: 0;
		padding: 7px 3px;
		overflow: hidden;
		-webkit-border-radius: 0 4px 4px 0;
		-moz-border-radius: 0 4px 4px 0;
		border-radius: 0 4px 4px 0;
		-moz-background-clip : padding;
		-webkit-background-clip: padding-box;
		background-clip: padding-box;
		background: #ccc;
		background-image: -webkit-gradient(linear, left bottom, left top, color-stop(0, #ccc), color-stop(0.6, #eee));
		background-image: -webkit-linear-gradient(center bottom, #ccc 0%, #eee 60%);
		background-image: -moz-linear-gradient(center bottom, #ccc 0%, #eee 60%);
		background-image: -o-linear-gradient(bottom, #ccc 0%, #eee 60%);
		background-image: -ms-linear-gradient(top, #cccccc 0%,#eeeeee 60%);
		filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#cccccc', endColorstr='#eeeeee',GradientType=0 );
		
		background-image: linear-gradient(top, #cccccc 0%,#eeeeee 60%);
		border-left: 1px solid #aaa;

		&.treedropdownfield-open-tree {
			background: transparent;
			border: none;
		}
		
		a {
			text-decoration: none;
			display: block;
			border: 0;
			margin: 0;
			opacity: 0.5;
		}
	}
	
	a.jstree-loading .jstree-pageicon { 
		// Apply to .jstree-pageicon since .jstree-icon is hidden
		background: #fff url("../images/network-save.gif") center center no-repeat; 
	}
}