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

:root {
  --primary-color: #475569;
  --primary-hover: #334155;
  --success-color: #059669;
  --success-light: #dcfce7;
  --error-color: #dc2626;
  --error-light: #fef2f2;
  --warning-color: #d97706;
  --warning-light: #fef3c7;
  --info-color: #0284c7;
  --info-light: #dbeafe;
  --bg-color: #f1f5f9;
  --sidebar-bg: #1e293b;
  --sidebar-text: #64748b;
  --sidebar-active: #94a3b8;
  --card-bg: #ffffff;
  --border-color: #e2e8f0;
  --text-primary: #334155;
  --text-secondary: #64748b;
  --text-light: #94a3b8;

  /* TC Colors */
  --tc0: #94a3b8;
  --tc1: #64748b;
  --tc2: #475569;
  --tc3: #334155;
  --tc4: #1e3a5f;
  --tc5: #1e40af;
  --tc6: #3730a3;
  --tc7: #4c1d95;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-primary);
  line-height: 1.6;
}

.app-container {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar {
  width: 260px;
  background-color: var(--sidebar-bg);
  color: var(--sidebar-text);
  padding: 20px 0;
  position: fixed;
  height: 100vh;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
}

.sidebar-header {
  padding: 0 20px 20px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  margin-bottom: 20px;
}

.sidebar-logo {
  height: 44px;
  margin-bottom: 12px;
  filter: brightness(0) invert(1);
  opacity: 0.95;
}

.sidebar-title {
  font-size: 0.9rem;
  font-weight: 600;
  color: rgba(255,255,255,0.85);
  letter-spacing: 0.02em;
}

.sidebar-subtitle {
  font-size: 0.7rem;
  color: var(--sidebar-text);
  margin-top: 4px;
}

.sidebar-footer {
  margin-top: auto;
  padding: 16px 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.sim-badge {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 4px;
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  background: rgba(234, 179, 8, 0.2);
  color: #fbbf24;
  border: 1px solid rgba(234, 179, 8, 0.3);
}

.nav-section {
  margin-bottom: 24px;
}

.nav-section-title {
  padding: 0 20px;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #64748b;
  margin-bottom: 8px;
}

.nav-item {
  display: flex;
  align-items: center;
  padding: 10px 20px;
  color: var(--sidebar-text);
  text-decoration: none;
  cursor: pointer;
  transition: all 0.2s;
  border-left: 3px solid transparent;
  font-size: 0.875rem;
}

.nav-item:hover {
  background-color: rgba(255, 255, 255, 0.05);
  color: #fff;
}

.nav-item.active {
  background-color: rgba(255, 255, 255, 0.08);
  color: #fff;
  border-left-color: #94a3b8;
}

.nav-item-icon {
  width: 20px;
  height: 20px;
  margin-right: 12px;
  opacity: 0.7;
}

.nav-item.active .nav-item-icon {
  opacity: 1;
}

/* Main Content */
.main-content {
  flex: 1;
  margin-left: 260px;
  padding: 24px;
  min-height: 100vh;
}

.page-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
}

.page-title {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--text-primary);
}

.page-description {
  color: var(--text-secondary);
  margin-top: 4px;
  font-size: 0.875rem;
}

.header-right {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* Cards */
.card {
  background: var(--card-bg);
  border-radius: 12px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  padding: 24px;
  margin-bottom: 24px;
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.card-title {
  font-size: 1rem;
  font-weight: 600;
}

.card-subtitle {
  font-size: 0.75rem;
  color: var(--text-secondary);
}

/* Grids */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.grid-6 {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 10px;
}

.metrics-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-bottom: 24px;
}

/* Stat Box */
.stat-box {
  padding: 12px 14px;
  background: var(--bg-color);
  border-radius: 6px;
  border: 1px solid var(--border-color);
}

.stat-label {
  font-size: 0.65rem;
  color: var(--text-secondary);
  margin-bottom: 4px;
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.stat-value {
  font-weight: 600;
  font-size: 0.95rem;
  font-family: ui-monospace, 'SF Mono', monospace;
  color: var(--text-primary);
}

.stat-value.success { color: var(--success-color); }
.stat-value.warning { color: var(--warning-color); }
.stat-value.error { color: var(--error-color); }

/* Metric Cards */
.metric-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  padding: 20px;
  text-align: center;
}

.metric-label {
  font-size: 0.7rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 8px;
}

.metric-value {
  font-size: 2rem;
  font-weight: 600;
  color: var(--text-primary);
  font-variant-numeric: tabular-nums;
}

.metric-value.success { color: var(--success-color); }
.metric-value.warning { color: var(--warning-color); }

.metric-unit {
  font-size: 0.7rem;
  color: var(--text-secondary);
  margin-top: 4px;
}

/* Status Badge */
.status-badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  border-radius: 9999px;
  font-size: 0.75rem;
  font-weight: 500;
}

.status-badge.success {
  background-color: var(--success-light);
  color: #166534;
}

.status-badge.error {
  background-color: var(--error-light);
  color: #991b1b;
}

.status-badge.warning {
  background-color: var(--warning-light);
  color: #92400e;
}

.status-badge.info {
  background-color: var(--info-light);
  color: #1e40af;
}

.status-badge.neutral {
  background-color: var(--bg-color);
  color: var(--text-secondary);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 20px;
  border: none;
  border-radius: 8px;
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
}

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

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

.btn-primary:disabled {
  background-color: #94a3b8;
  cursor: not-allowed;
}

.btn-secondary {
  background-color: #f1f5f9;
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  background-color: #e2e8f0;
}

.btn-success {
  background-color: var(--success-color);
  color: #fff;
}

.btn-danger {
  background-color: var(--error-color);
  color: #fff;
}

.btn-block {
  width: 100%;
}

.btn-sm {
  padding: 6px 12px;
  font-size: 0.75rem;
}

/* Tables */
.table {
  width: 100%;
  border-collapse: collapse;
}

.table th,
.table td {
  padding: 12px;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

.table th {
  font-weight: 600;
  color: var(--text-secondary);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background: var(--bg-color);
}

.table tbody tr:hover {
  background-color: #f8fafc;
}

.table td {
  font-size: 0.875rem;
}

/* Forms */
.form-group {
  margin-bottom: 16px;
}

.form-label {
  display: block;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  font-size: 0.875rem;
  background: var(--card-bg);
  transition: border-color 0.2s, box-shadow 0.2s;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(71, 85, 105, 0.1);
}

.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 12px;
}

/* Progress */
.progress-container {
  margin-bottom: 16px;
}

.progress-header {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  margin-bottom: 6px;
}

.progress-bar {
  height: 6px;
  background: var(--bg-color);
  border-radius: 3px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: var(--primary-color);
  transition: width 0.1s;
  width: 0%;
  border-radius: 3px;
}

/* Traffic Classes */
.tc-badges {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.tc-badge {
  padding: 6px 12px;
  border-radius: 6px;
  color: #fff;
  font-size: 0.75rem;
  font-weight: 600;
}

.tc-btn {
  padding: 8px 14px;
  border-radius: 6px;
  border: 2px solid var(--border-color);
  background: #fff;
  color: var(--text-secondary);
  font-weight: 600;
  font-size: 0.75rem;
  cursor: pointer;
  transition: all 0.2s;
}

.tc-btn.active {
  background: var(--bg-color);
}

.tc-btn:disabled {
  cursor: not-allowed;
  opacity: 0.6;
}

.tc0 { background: var(--tc0); }
.tc1 { background: var(--tc1); }
.tc2 { background: var(--tc2); }
.tc3 { background: var(--tc3); }
.tc4 { background: var(--tc4); }
.tc5 { background: var(--tc5); }
.tc6 { background: var(--tc6); }
.tc7 { background: var(--tc7); }

.tc-btn.tc0.active { border-color: var(--tc0); color: var(--tc0); background: rgba(148,163,184,0.1); }
.tc-btn.tc1.active { border-color: var(--tc1); color: var(--tc1); background: rgba(100,116,139,0.1); }
.tc-btn.tc2.active { border-color: var(--tc2); color: var(--tc2); background: rgba(71,85,105,0.1); }
.tc-btn.tc3.active { border-color: var(--tc3); color: var(--tc3); background: rgba(51,65,85,0.1); }
.tc-btn.tc4.active { border-color: var(--tc4); color: var(--tc4); background: rgba(30,58,95,0.1); }
.tc-btn.tc5.active { border-color: var(--tc5); color: var(--tc5); background: rgba(30,64,175,0.1); }
.tc-btn.tc6.active { border-color: var(--tc6); color: var(--tc6); background: rgba(55,48,163,0.1); }
.tc-btn.tc7.active { border-color: var(--tc7); color: var(--tc7); background: rgba(76,29,149,0.1); }

/* GCL Heatmap */
.gcl-heatmap {
  display: grid;
  gap: 2px;
}

.gcl-cell {
  height: 28px;
  border-radius: 3px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.65rem;
  font-weight: 600;
  transition: all 0.2s;
}

.gcl-cell.open {
  color: #fff;
}

.gcl-cell.closed {
  background: var(--bg-color);
  color: var(--text-light);
  border: 1px solid var(--border-color);
}

/* Topology */
.topology {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  padding: 30px 20px;
  background: var(--bg-color);
  border-radius: 8px;
}

.topology-node {
  min-width: 100px;
  padding: 14px 18px;
  background: var(--card-bg);
  border: 2px solid var(--border-color);
  border-radius: 10px;
  text-align: center;
  position: relative;
}

.topology-node.gm {
  border-color: var(--success-color);
  min-width: 120px;
}

.topology-node.slave {
  border-color: var(--info-color);
}

.topology-type {
  font-size: 0.6rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 4px;
}

.topology-name {
  font-weight: 600;
  font-size: 0.9rem;
  margin-bottom: 4px;
}

.topology-mac {
  font-size: 0.6rem;
  color: var(--text-secondary);
  font-family: monospace;
}

.topology-role {
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  padding: 2px 10px;
  border-radius: 4px;
  font-size: 0.6rem;
  font-weight: 700;
  color: #fff;
  white-space: nowrap;
}

.topology-role.gm { background: var(--success-color); }
.topology-role.slave { background: var(--info-color); }

.topology-link {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.topology-line {
  width: 50px;
  height: 2px;
  background: var(--border-color);
}

.topology-line.connected {
  background: var(--success-color);
}

.topology-port {
  font-size: 0.6rem;
  color: var(--text-secondary);
}

/* Canvas / SVG */
canvas, svg.graph {
  width: 100%;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  background: #fff;
}

/* Link Status */
.link-status {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  border-radius: 4px;
  font-size: 0.7rem;
  font-weight: 500;
}

.link-status.up {
  background: var(--success-light);
  color: #166534;
}

.link-status.down {
  background: var(--bg-color);
  color: var(--text-secondary);
}

.link-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
}

.link-status.up .link-dot { background: #166534; }
.link-status.down .link-dot { background: #999; }

/* Timeline */
.timeline-container {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.timeline-row {
  display: flex;
  align-items: center;
  gap: 12px;
}

.timeline-label {
  width: 50px;
  font-size: 0.75rem;
  font-weight: 600;
}

.timeline-bar {
  flex: 1;
  display: flex;
  height: 26px;
  border-radius: 4px;
  overflow: hidden;
  border: 1px solid var(--border-color);
}

.timeline-slot {
  height: 100%;
  border-right: 1px solid rgba(255,255,255,0.3);
}

.timeline-slot:last-child {
  border-right: none;
}

.timeline-name {
  width: 60px;
  font-size: 0.65rem;
  color: var(--text-secondary);
  text-align: right;
}

.timeline-labels {
  display: flex;
  justify-content: space-between;
  margin-top: 8px;
  padding-left: 62px;
  padding-right: 72px;
  font-size: 0.65rem;
  color: var(--text-secondary);
}

/* Alert */
.alert {
  padding: 12px 16px;
  border-radius: 8px;
  margin-bottom: 16px;
  font-size: 0.875rem;
}

.alert-error {
  background-color: var(--error-light);
  color: #991b1b;
  border: 1px solid #fecaca;
}

.alert-success {
  background-color: var(--success-light);
  color: #166534;
  border: 1px solid #bbf7d0;
}

.alert-info {
  background-color: var(--info-light);
  color: #1e40af;
  border: 1px solid #bfdbfe;
}

.alert-warning {
  background-color: var(--warning-light);
  color: #92400e;
  border: 1px solid #fde68a;
}

/* Section */
.section {
  margin-bottom: 24px;
}

.section-header {
  margin-bottom: 12px;
}

.section-title {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.section-desc {
  font-size: 0.75rem;
  color: var(--text-secondary);
  line-height: 1.4;
}

.section-note {
  margin-top: 8px;
  padding: 8px 12px;
  background: var(--bg-color);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  font-size: 0.7rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* Result Analysis */
.result-analysis {
  margin-top: 16px;
  padding: 14px;
  background: var(--bg-color);
  border-radius: 8px;
  font-size: 0.8rem;
  color: var(--text-secondary);
}

/* Legend */
.legend {
  display: flex;
  gap: 16px;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.75rem;
  color: var(--text-secondary);
}

.legend-color {
  width: 12px;
  height: 12px;
  border-radius: 2px;
}

/* Packet Table */
.packet-table {
  font-size: 0.7rem;
  font-family: ui-monospace, monospace;
  max-height: 200px;
  overflow-y: auto;
  background: var(--bg-color);
  border-radius: 6px;
  padding: 10px;
}

.packet-table table {
  width: 100%;
  border-collapse: collapse;
}

.packet-table th,
.packet-table td {
  padding: 4px 8px;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

.packet-table th {
  color: var(--text-secondary);
  font-weight: 600;
}

/* Responsive */
@media (max-width: 1400px) {
  .grid-6 { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 1200px) {
  .grid-2 { grid-template-columns: 1fr; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .metrics-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .sidebar {
    width: 60px;
    padding: 10px 0;
  }
  .sidebar-logo,
  .sidebar-title,
  .sidebar-subtitle,
  .nav-section-title,
  .nav-item span,
  .sim-badge {
    display: none;
  }
  .nav-item {
    justify-content: center;
    padding: 12px;
  }
  .nav-item-icon {
    margin-right: 0;
  }
  .main-content {
    margin-left: 60px;
  }
  .metrics-grid,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }
}