.chart-container {
            position: relative;
            width: 100%;
            max-width: 600px;
            margin-left: auto;
            margin-right: auto;
            height: 350px;
            max-height: 400px;
        }
        @media (max-width: 640px) {
            .chart-container {
                height: 300px;
            }
        }