* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    background: aliceblue;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    color: #333;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 16px 20px;
}

h2 {
    text-align: center;
    color: #3F51B5;
    margin-bottom: 8px;
    font-size: 1.3rem;
}

#sankey-chart {
    width: 100%;
    min-height: 440px;
}

.source {
    text-align: center;
    font-size: 0.8rem;
    color: #888;
    margin-top: 4px;
}