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

body {
  font-family:
    "Segoe UI",
    system-ui,
    -apple-system,
    sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 20px;
}

.chart-container {
  background: white;
  border-radius: 16px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
  padding: 30px;
  max-width: 900px;
  width: 100%;
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.chart-header {
  text-align: center;
  margin-bottom: 30px;
}

.chart-title {
  font-size: 2rem;
  font-weight: 700;
  color: #2d3748;
  margin-bottom: 8px;
}

.chart-subtitle {
  font-size: 1rem;
  color: #718096;
  font-weight: 400;
}

#chart {
  width: 100%;
  height: 400px;
}

/* Custom C3.js styles */
.c3-chart-arcs-title {
  font-size: 16px;
  font-weight: 600;
}

.c3-axis text,
.c3-legend-item text {
  font-family: "Segoe UI", sans-serif;
  font-size: 12px;
  fill: #4a5568;
}

.c3-tooltip {
  background: rgba(255, 255, 255, 0.95);
  border: 1px solid #e2e8f0;
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  backdrop-filter: blur(10px);
}

.c3-tooltip td {
  font-family: "Segoe UI", sans-serif;
  color: #2d3748;
  font-size: 12px;
  padding: 4px 8px;
}

.c3-tooltip th {
  background: #4c51bf;
  color: white;
  border-radius: 4px 4px 0 0;
  font-weight: 600;
}

.chart-footer {
  text-align: center;
  margin-top: 20px;
  color: #718096;
  font-size: 0.875rem;
}

/* Responsive design */
@media (max-width: 768px) {
  .chart-container {
    padding: 20px;
    margin: 10px;
  }

  .chart-title {
    font-size: 1.5rem;
  }

  #chart {
    height: 300px;
  }
}