:root {
  --bg-main: hsl(224, 71%, 4%);
  --bg-surface: hsl(222, 47%, 9%);
  --bg-card: hsl(222, 47%, 13%);
  --bg-card-hover: hsl(222, 47%, 17%);
  --border: hsl(217, 33%, 20%);
  --border-focus: hsl(158, 64%, 48%);
  --text-main: hsl(210, 40%, 98%);
  --text-muted: hsl(215, 20%, 65%);
  --text-dim: hsl(215, 16%, 45%);
  --accent-green: hsl(158, 64%, 48%);
  --accent-cyan: hsl(199, 89%, 48%);
  --accent-amber: hsl(43, 96%, 56%);
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, monospace;
}

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

body {
  background-color: var(--bg-main);
  color: var(--text-main);
  font-family: var(--font-sans);
  line-height: 1.6;
  letter-spacing: -0.011em;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

header {
  border-bottom: 1px solid var(--border);
  background: hsla(224, 71%, 4%, 0.85);
  backdrop-filter: blur(12px);
  position: sticky;
  top: 0;
  z-index: 50;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--text-main);
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: -0.02em;
}

.brand-badge {
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--accent-cyan);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.nav-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  transition: color 0.15s ease;
}

.nav-links a:hover, .nav-links a.active {
  color: var(--text-main);
}

.btn-primary {
  background: var(--accent-green);
  color: hsl(158, 90%, 8%);
  padding: 0.5rem 1rem;
  border-radius: 6px;
  font-weight: 600;
  font-size: 0.875rem;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  transition: opacity 0.15s ease, transform 0.1s ease;
}

.btn-primary:hover {
  opacity: 0.92;
  transform: translateY(-1px);
}

.btn-secondary {
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text-main);
  padding: 0.5rem 1rem;
  border-radius: 6px;
  font-weight: 600;
  font-size: 0.875rem;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  transition: background 0.15s ease;
}

.btn-secondary:hover {
  background: var(--bg-card-hover);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2.5rem 1.5rem;
  flex: 1;
}

.hero {
  padding: 3rem 0;
  text-align: center;
  max-width: 840px;
  margin: 0 auto;
}

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: hsla(199, 89%, 48%, 0.1);
  color: var(--accent-cyan);
  border: 1px solid hsla(199, 89%, 48%, 0.25);
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
  font-family: var(--font-mono);
}

.pulse-dot {
  width: 8px;
  height: 8px;
  background: var(--accent-green);
  border-radius: 50%;
  box-shadow: 0 0 10px var(--accent-green);
}

.hero h1 {
  font-size: 2.75rem;
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.035em;
  margin-bottom: 1.25rem;
}

.hero p {
  font-size: 1.1rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 2rem;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.telemetry-bar {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem 1.75rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1.5rem;
  margin-bottom: 3.5rem;
}

.telemetry-item {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.telemetry-label {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.telemetry-value {
  font-family: var(--font-mono);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.section-title {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.025em;
  margin-bottom: 0.5rem;
}

.section-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 1.75rem;
}

.grid-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.5rem;
  margin-bottom: 3.5rem;
}

.card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: border-color 0.15s ease, transform 0.15s ease;
}

.card:hover {
  border-color: hsl(217, 33%, 35%);
  transform: translateY(-2px);
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1rem;
}

.card-title {
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: -0.015em;
}

.status-badge {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.2rem 0.55rem;
  border-radius: 4px;
}

.badge-online {
  background: hsla(158, 64%, 48%, 0.15);
  color: var(--accent-green);
  border: 1px solid hsla(158, 64%, 48%, 0.3);
}

.badge-backbone {
  background: hsla(199, 89%, 48%, 0.15);
  color: var(--accent-cyan);
  border: 1px solid hsla(199, 89%, 48%, 0.3);
}

.card-metrics {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
  background: var(--bg-card);
  border-radius: 6px;
  padding: 0.85rem;
  margin: 1rem 0;
  font-family: var(--font-mono);
  font-size: 0.8rem;
}

.card-metric-val {
  font-weight: 700;
  color: var(--text-main);
}

.card-metric-lbl {
  color: var(--text-dim);
  font-size: 0.7rem;
}

.architecture-banner {
  background: linear-gradient(135deg, hsl(222, 47%, 11%) 0%, hsl(224, 71%, 6%) 100%);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 2.25rem;
  margin-bottom: 3.5rem;
}

.arch-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.arch-steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.arch-step {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.25rem;
}

.arch-step-num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-cyan);
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.arch-step h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.35rem;
}

.arch-step p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.5;
}

footer {
  border-top: 1px solid var(--border);
  background: var(--bg-surface);
  padding: 2rem 1.5rem;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}