th.sortable {
    cursor: pointer;
    padding-right: 18px;
    position: relative;
}

th.sortable:before,
th.sortable:after {
    border: 4px solid transparent;
    content: "";
    display: block;
    height: 0;
    right: 5px;
    top: 75%;
    position: absolute;
    width: 0;
}

th.sortable-bottom:before,
th.sortable-bottom:after {
    top: 50% !important;
}

th.sortable:before {
    border-bottom-color: #666;
    margin-top: -9px;
}

th.sortable:after {
    border-top-color: #666;
    margin-top: 1px;
}