.tooltip {
    position: relative;
    display: inline-block;
}

.tooltip::before {
    content: attr(data-tooltip);
    position: absolute;
    top: -30px;
    left: 0;
    background-color: #333;
    color: #fff;
    padding: 5px;
    border-radius: 3px;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s ease, visibility 0.2s ease;
}

.tooltip:hover::before {
    opacity: 1;
    visibility: visible;
}