Template:HoverEffect/Styles.css

.hover-tooltip {
    position: relative;
    text-decoration: none;
    color: blue;
    cursor: pointer;
}

.hover-tooltip span {
    display: none;
    position: absolute;
    top: 1.5em;
    left: 0;
    background-color: white;
    border: 1px solid gray;
    border-radius: 5px;
    padding: 5px;
    box-shadow: 0px 4px 6px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    white-space: nowrap;
    font-size: 90%;
}

.hover-tooltip:hover span {
    display: block;
}