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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: #333;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
}

header {
    text-align: center;
    color: white;
    margin-bottom: 40px;
}

header h1 {
    font-size: 3em;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.subtitle {
    font-size: 1.2em;
    opacity: 0.9;
}

.metrics-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.metric-card {
    background: white;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.metric-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 12px rgba(0,0,0,0.15);
}

.metric-card h3 {
    font-size: 0.9em;
    color: #666;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 15px;
}

.metric-value {
    font-size: 2em;
    font-weight: bold;
    color: #667eea;
    margin-bottom: 5px;
}

.metric-label {
    font-size: 0.85em;
    color: #999;
}

.chart-controls {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-bottom: 20px;
}

.tab-btn {
    padding: 12px 30px;
    border: none;
    background: white;
    color: #667eea;
    font-size: 1em;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.tab-btn:hover {
    background: #f0f0f0;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.15);
}

.tab-btn.active {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.chart-container {
    background: white;
    border-radius: 12px;
    padding: 30px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    margin-bottom: 30px;
}

footer {
    text-align: center;
    color: white;
    padding: 20px;
}

footer p {
    margin: 5px 0;
    opacity: 0.9;
}

.data-source {
    font-size: 0.9em;
    opacity: 0.7;
}

@media (max-width: 768px) {
    header h1 {
        font-size: 2em;
    }

    .metrics-cards {
        grid-template-columns: 1fr;
    }

    .tab-btn {
        padding: 10px 20px;
        font-size: 0.9em;
    }

    .chart-container {
        padding: 15px;
    }
}