File: engine/modules/core/manager/css/manager.css

.manager-tree li {
    display: block;
    padding-left: 20px;
    margin-left: 0;
    margin-top: 4px;
}
.manager-tree ul {
    padding: 0;
    margin: 0;
}
.manager-tree  li.expanded ul {
    margin-left: 4px;
    border-bottom: 1px solid #dedede;
}
.manager-tree li a {
    display: inline-block;
    padding: 3px;
    border-radius: 8px;
}
.manager-tree li a:hover {
    background-color: #ddd;
}

.manager-tree li a {
    text-decoration: none;
    padding-left: 18px;
}


.manager-tree li > a.has-children {
    background-image: url('plus.gif');
    background-repeat: no-repeat;
    background-position: center left;

}

.manager-tree li.expanded > a.has-children {
    border: 1px solid #ddd;
    background-image: url('minus.gif');
}

.manager-tree li.expanded > ul > li {
    border-left: 1px solid #ddd;
}

.manager-main-category {
    font-weight: bold;
}