#chartContainer {
    width: 100%;
    height: 350px;
}

#barTooltip {
    position: absolute;
    background: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 4px 8px;
    border-radius: 4px;
    display: none;
    pointer-events: none;
    font-size: 12px;
}