table.tablesorter thead tr .header {
    background-image: none !important;
    cursor: pointer;
    position: relative;
    padding-right: 18px !important;
    user-select: none;
}

table.tablesorter thead tr .header::after {
    content: '⇅';
    position: absolute;
    right: 4px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 11px;
    line-height: 1;
    opacity: 0.35;
}

table.tablesorter thead tr .headerSortUp::after {
    content: '▲';
    opacity: 1;
}

table.tablesorter thead tr .headerSortDown::after {
    content: '▼';
    opacity: 1;
}

table.tablesorter thead tr .headerSortUp,
table.tablesorter thead tr .headerSortDown {
    background-color: #d9e8f7 !important;
}