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

:root {
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --primary-light: #a5b4fc;
  --accent: #f59e0b;
  --accent-dark: #d97706;
  --success: #10b981;
  --danger: #ef4444;
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --bg-light: #f8fafc;
  --bg-card: #ffffff;
  --border: #e2e8f0;
  --shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.1);
  --radius: 12px;
  --cluster-a: #3b82f6;
  --cluster-b: #f97316;
  --cluster-c: #10b981;
  --ego-color: #8b5cf6;
  --redundant-color: #ef4444;
  --nonredundant-color: #3b82f6;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen,
    Ubuntu, Cantarell, sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background: linear-gradient(135deg, #312e81 0%, #4338ca 50%, #6366f1 100%);
  min-height: 100vh;
  padding: 20px;
}

.container {
  max-width: 1440px;
  margin: 0 auto;
  background: #fff;
  border-radius: 16px;
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}

/* Header */
header {
  background: linear-gradient(135deg, #312e81, #4f46e5);
  color: #fff;
  padding: 36px 30px;
  text-align: center;
}

header h1 {
  font-size: 2.1rem;
  font-weight: 700;
  margin-bottom: 8px;
}

header .subtitle {
  font-size: 1.05rem;
  opacity: 0.9;
  max-width: 700px;
  margin: 0 auto;
}

/* Main layout */
.main-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  gap: 24px;
  padding: 24px;
  align-items: start;
}

.canvas-section {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

.canvas-container {
  background: #fff;
  border-radius: var(--radius);
  padding: 12px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  width: 100%;
  max-width: 720px;
}

#networkCanvas {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 8px;
  cursor: default;
}

#networkCanvas.edge-mode {
  cursor: crosshair;
}

.canvas-legend {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  justify-content: center;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.82rem;
  color: var(--text-secondary);
}

.legend-dot {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  border: 2px solid rgba(0, 0, 0, 0.1);
}

.legend-dot.ego { background: var(--ego-color); }
.legend-dot.cluster-a { background: var(--cluster-a); }
.legend-dot.cluster-b { background: var(--cluster-b); }
.legend-dot.cluster-c { background: var(--cluster-c); }

.legend-line {
  width: 28px;
  height: 3px;
  border-radius: 2px;
}

.legend-line.redundant {
  background: var(--redundant-color);
  opacity: 0.7;
}

.legend-line.nonredundant {
  background: var(--nonredundant-color);
}

/* Comparison section */
.comparison-section {
  width: 100%;
  max-width: 720px;
}

.comparison-section h3 {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--primary-dark);
  margin-bottom: 12px;
  text-align: center;
}

.comparison-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.comparison-card {
  background: var(--bg-light);
  border-radius: var(--radius);
  padding: 16px;
  border: 1px solid var(--border);
  text-align: center;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.comparison-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.comparison-card.high-holes {
  border-top: 3px solid var(--success);
}

.comparison-card.low-holes {
  border-top: 3px solid var(--danger);
}

.comparison-header {
  margin-bottom: 8px;
}

.comparison-badge {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 600;
  color: #fff;
}

.comparison-badge.high { background: var(--success); }
.comparison-badge.low { background: var(--danger); }

.comparison-card canvas {
  display: block;
  margin: 0 auto;
  max-width: 100%;
}

.comparison-stats {
  display: flex;
  flex-direction: column;
  gap: 2px;
  font-size: 0.82rem;
  color: var(--text-secondary);
  margin-top: 8px;
}

.comparison-stats strong {
  color: var(--primary-dark);
}

/* Sidebar */
.sidebar {
  display: flex;
  flex-direction: column;
  gap: 16px;
  position: sticky;
  top: 24px;
}

.panel {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 18px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.panel h2 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--primary-dark);
  margin-bottom: 14px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--primary);
}

/* Controls */
.control-group {
  margin-bottom: 14px;
}

.control-group label {
  display: block;
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.preset-buttons {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 6px;
}

.btn {
  padding: 9px 14px;
  border: none;
  border-radius: 8px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  text-align: center;
}

.btn-preset {
  background: var(--bg-light);
  color: var(--text-secondary);
  border: 2px solid var(--border);
}

.btn-preset.active {
  background: var(--primary);
  color: #fff;
  border-color: var(--primary);
}

.btn-preset:hover:not(.active) {
  border-color: var(--primary-light);
  color: var(--primary-dark);
}

.toggle-row {
  display: flex;
  gap: 8px;
}

.btn-toggle {
  background: var(--bg-light);
  color: var(--text-secondary);
  border: 2px solid var(--border);
  width: 100%;
}

.btn-toggle.active {
  background: var(--primary);
  color: #fff;
  border-color: var(--primary);
}

.button-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-top: 12px;
}

.btn-secondary {
  background: #fff;
  color: var(--primary);
  border: 2px solid var(--primary);
}

.btn-secondary:hover {
  background: var(--primary);
  color: #fff;
}

.btn-secondary.active {
  background: var(--primary-dark);
  color: #fff;
}

.help-text {
  font-size: 0.78rem;
  color: var(--accent-dark);
  margin-top: 6px;
  min-height: 1.2em;
  text-align: center;
}

/* Metrics */
.metric-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}

.metric-item {
  background: var(--bg-light);
  padding: 10px;
  border-radius: 8px;
  text-align: center;
}

.metric-item.highlight {
  background: #eef2ff;
  border: 1px solid var(--primary-light);
}

.metric-label {
  display: block;
  font-size: 0.7rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.3px;
  margin-bottom: 4px;
}

.metric-value {
  display: block;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.metric-item.highlight .metric-value {
  color: var(--primary-dark);
}

/* Brokerage Gauge */
.brokerage-gauge {
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px solid var(--border);
}

.gauge-label {
  display: block;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

.gauge-bar {
  height: 14px;
  background: var(--bg-light);
  border-radius: 7px;
  overflow: hidden;
  border: 1px solid var(--border);
}

.gauge-fill {
  height: 100%;
  border-radius: 7px;
  background: linear-gradient(90deg, var(--danger), var(--accent), var(--success));
  transition: width 0.5s ease;
  width: 0%;
}

.gauge-value {
  display: block;
  text-align: right;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--primary-dark);
  margin-top: 4px;
}

/* Formulas */
.formula-item {
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 8px;
}

.formula-item:last-child {
  border-bottom: none;
}

.formula-name {
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-secondary);
  white-space: nowrap;
}

.formula-expr {
  font-family: "Cambria Math", "Latin Modern Math", Georgia, serif;
  font-size: 0.88rem;
  color: var(--text-primary);
}

/* Education section */
.education-section {
  padding: 30px;
  border-top: 1px solid var(--border);
}

.info-box {
  background: linear-gradient(135deg, #eef2ff, #e0e7ff);
  padding: 24px;
  border-radius: var(--radius);
  border-left: 4px solid var(--primary);
  margin-bottom: 24px;
}

.info-box h3 {
  color: var(--primary-dark);
  margin-bottom: 10px;
  font-size: 1.15rem;
}

.info-box p {
  color: var(--text-primary);
  line-height: 1.8;
}

.insight-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 18px;
}

.insight-card {
  background: #fff;
  padding: 20px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  border-top: 3px solid var(--accent);
  transition: transform 0.2s ease;
}

.insight-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

.insight-card h4 {
  color: var(--accent-dark);
  margin-bottom: 10px;
  font-size: 1rem;
}

.insight-card p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.7;
}

/* Footer */
footer {
  background: var(--bg-light);
  padding: 18px 30px;
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.85rem;
  border-top: 1px solid var(--border);
}

/* Responsive */
@media (max-width: 1024px) {
  .main-layout {
    grid-template-columns: 1fr;
    gap: 0;
    padding: 0;
  }

  .sidebar {
    border-top: 1px solid var(--border);
    background: var(--bg-light);
    position: static;
    flex-direction: row;
    flex-wrap: wrap;
    padding: 20px;
    gap: 12px;
  }

  .sidebar .panel {
    flex: 1;
    min-width: 280px;
  }

  .canvas-section {
    padding: 16px;
  }
}

@media (max-width: 640px) {
  body {
    padding: 8px;
  }

  header {
    padding: 24px 16px;
  }

  header h1 {
    font-size: 1.5rem;
  }

  header .subtitle {
    font-size: 0.9rem;
  }

  .canvas-section {
    padding: 12px;
  }

  .comparison-grid {
    grid-template-columns: 1fr;
  }

  .sidebar {
    flex-direction: column;
    padding: 12px;
  }

  .sidebar .panel {
    min-width: auto;
  }

  .metric-grid {
    grid-template-columns: 1fr 1fr;
    gap: 6px;
  }

  .preset-buttons {
    grid-template-columns: 1fr;
  }

  .education-section {
    padding: 16px;
  }
}