.tooltip
{
    position: relative;
    display: inline-block;
    border-bottom: 1px dotted black;
}

.tooltip .tooltiptext {
    visibility: hidden;
    width: 120px;
    background-color: black;
    color: #fff;
    text-align: center;
    border-radius: 6px;
    padding: 5px 0;
    /* Position the tooltip */
    position: absolute;
    z-index: 1;
    width: 120px;
    bottom: 100%;
    left: 50%;
    margin-left: -60px; /* Use half of the width (120/2 = 60), to center the tooltip */
}

.tooltip:hover .tooltiptext {
    visibility: visible;
}

    .tooltip .tooltiptext::after {
        content: " ";
        position: absolute;
        top: 100%; /* At the bottom of the tooltip */
        left: 50%;
        margin-left: -5px;
        border-width: 5px;
        border-style: solid;
        border-color: black transparent transparent transparent;
    }