src/manager/styles/subject-tree.css
/* SUBJECTS TREE */

.subjects .tree.jstree {
  font-size: 13px;
}

.hidden-icon {
  display: none !important;
}


.subject-search {
  float: left;
  position: relative;
  width: 248px;
  height: 30px;
  margin: 20px;
}

.subject-search .search {
  position: absolute;
  top: 50%;
  left: 6px;
  z-index: 1000;
  width: 10px;
  height: 20px;
  margin-top: -10px;
  -webkit-box-sizing: content-box;
  -moz-box-sizing: content-box;
  box-sizing: content-box;
}

.subject-search .search:before {
  position: absolute;
  top: 50%;
  left: 0;
  width: 6px;
  height: 6px;
  margin-top: -6px;
  background: 0 0;
  border: 3px solid gray;
  -webkit-border-radius: 12px;
  -moz-border-radius: 12px;
  border-radius: 12px;
  content: "";
  -webkit-box-sizing: content-box;
  -moz-box-sizing: content-box;
  box-sizing: content-box;
}

.subject-search  .search:after {
  position: absolute;
  top: 50%;
  left: 10px;
  width: 3px;
  height: 7px;
  margin-top: 2px;
  background-color: gray;
  content: "";
  -webkit-transform: rotate(-45deg);
  -moz-transform: rotate(-45deg);
  -ms-transform: rotate(-45deg);
  -o-transform: rotate(-45deg);
  transform: rotate(-45deg);
  -webkit-box-sizing: content-box;
  -moz-box-sizing: content-box;
  box-sizing: content-box;
}

.subjects #search_subject {
  outline: 0;
  -webkit-box-sizing: content-box;
  -moz-box-sizing: content-box;
  box-sizing: content-box;
  -webkit-appearance: none;
  position: absolute;
  display: inline-block;
  width: 206px;
  height: 20px;
  padding: 4px 18px 4px 22px;
  font-weight: 400;
  color: #555;
  vertical-align: middle;
  background-color: #fff;
  border: 1px solid #ccc;
  -webkit-border-radius: 4px;
  -moz-border-radius: 4px;
  border-radius: 4px;
  -webkit-box-shadow: inset 0 1px 1px rgba(0,0,0,.075);
  -moz-box-shadow: inset 0 1px 1px rgba(0,0,0,.075);
  box-shadow: inset 0 1px 1px rgba(0,0,0,.075);
  -webkit-transition: border linear .2s,box-shadow linear .2s;
  -moz-transition: border linear .2s,box-shadow linear .2s;
  -o-transition: border linear .2s,box-shadow linear .2s;
  transition: border linear .2s,box-shadow linear .2s;
  border-color: rgba(38,38,38,.3);
}

.subjects #search_subject:focus {
  border-color: rgba(38,38,38,.5);
}

.subjects li.not-empty > .jstree-wholerow {
  background: rgba(233, 255, 227, 0.5);
}

.subjects li.not-empty > .jstree-wholerow:hover {
  background-color: #e8eff7;
}

.subject-references-list {
  list-style-type: none;
}

.subject-references-list li {
  padding: 10px;
}