ul {
    list-style: none;   
}

header {
    cursor: pointer;
}
header:before {
    content: '\f0da';
    font-family: FontAwesome;
    font-style: normal;
    font-weight: normal;
    text-decoration: inherit;
    /*--adjust as necessary--*/
    color: #000;
    font-size: 14px;
    padding-right: 0.5em;
}
header.open:before {
    content: '\f0d7';
    font-family: FontAwesome;
    font-style: normal;
    font-weight: normal;
    text-decoration: inherit;
    /*--adjust as necessary--*/
    color: #000;
    font-size: 14px;
    padding-right: 0.5em;
}

.selected {
  background-color: #F3F3F3;
  font-weight: bold;
}