WebBuild/wwwroot/libs/frappe-gantt/css/frappe-gantt-custom.css

.gantt-container {
    width: auto;
    margin: 10px auto;
}

.chart-controls {
    text-align: center;
}

    .chart-controls > p {
        font-size: 1.2rem;
        font-weight: 500;
    }

.chart-label {
    font-size: 1.5rem;
    text-align: center;
    font-weight: 500;
}

.gantt-container .popup-wrapper {
    width: 300px;
    padding: 0 5px;
}

/*.popup-wrapper {
    border: 1px solid black;
    background-color: #F4F5F6;
}*/