.gridHeaderTr {
    background: #F9F9F9;
    cursor: pointer;
    border-bottom: 1px solid inherit;
    -webkit-transition: background 0.2s ease-in-out;
    transition: background 0.2s ease-in-out;
}
.gridHeading {
    background: #F9F9F9;
    position: relative;
    padding: .75rem;
}
.gridHeaderTrSpanColumnContentless, .gridHeaderTrSpanColumnNotLast, .gridHeaderTrSpanColumnNotLast.gridHeaderTrSpanColumnContentless{
    max-width: 30px;
    font-weight: bold;
    text-align: center;
    text-decoration: underline;
    border-bottom: 1px solid inherit;
    background: #eaeaea;
}

.gridHeaderTrSpanColumnContentless {
    border: none;
    text-decoration: none;
}

.gridHeadingInner {
    display: flex;
}

.verticalHeaderSpan {
    display: block;
    transform: rotate(-90deg);
    white-space: nowrap;
    margin-top: 25px;
}