.atp-tooltip {
    position: relative;
    cursor: pointer;
    border-bottom: 5px solid #F00;
}

.atp-tooltip:hover::after {
    content: attr(data-tooltip);
    position: absolute;
    background: #333;
    color: #fff;
    padding: 5px;
    border-radius: 5px;
    white-space: nowrap;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    z-index: 1000;
}