.fc .fc-event { cursor: pointer; }
.fc-tooltip {
    display: none;
    position: absolute;
    background: #333;
    color: #fff;
    padding: 5px;
    font-size: 12px;
    border-radius: 3px;
    z-index: 1000;
}
.fc-event:hover .fc-tooltip {
    display: block;
}