.custom-thead thead th {
    background-color: #CCCCCC;
    font-weight: normal;
    line-height: 1;
}

.sort-icon {
    display: inline-block;
    width: 1em;
    height: 1em;
    vertical-align: middle;
    margin-left: 2px;
    background-repeat: no-repeat;
    background-size: contain;
}

.sort-icon.invisible-icon {
    opacity: 0;
    pointer-events: none;
}

.sort-icon.asc {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='currentColor' viewBox='0 0 16 16'%3E%3Cpath fill-rule='evenodd' d='M8 15a.5.5 0 0 0 .5-.5V2.707l3.146 3.147a.5.5 0 0 0 .708-.708l-4-4a.5.5 0 0 0-.708 0l-4 4a.5.5 0 1 0 .708.708L7.5 2.707V14.5a.5.5 0 0 0 .5.5'/%3E%3C/svg%3E");
}

.sort-icon.desc {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='currentColor' viewBox='0 0 16 16'%3E%3Cpath fill-rule='evenodd' d='M8 1a.5.5 0 0 1 .5.5v11.793l3.146-3.147a.5.5 0 0 1 .708.708l-4 4a.5.5 0 0 1-.708 0l-4-4a.5.5 0 0 1 .708-.708L7.5 13.293V1.5A.5.5 0 0 1 8 1'/%3E%3C/svg%3E");
}