/* NodeRail Design System v1.0 */
:root {
  --nr-dark: #0f0f1a;
  --nr-navy: #1a1a2e;
  --nr-teal: #2dd4bf;
  --nr-teal-dim: #0d9488;
  --nr-white: #ffffff;
  --nr-off: #f7f7fb;
  --nr-border: #e4e4ef;
  --nr-text: #1a1a2e;
  --nr-muted: #6b7280;
  --nr-light-muted: #9ca3af;
  --nr-font: -apple-system, BlinkMacSystemFont, 'Inter', 'Segoe UI', Roboto, sans-serif;
  --nr-mono: 'SF Mono', 'Fira Code', 'Cascadia Code', monospace;
  --nr-radius: 12px;
  --nr-radius-sm: 6px;
  --nr-shadow: 0 1px 3px rgba(0,0,0,0.08), 0 4px 16px rgba(0,0,0,0.06);
  --nr-shadow-lg: 0 8px 32px rgba(0,0,0,0.12);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
html, body { height: auto; overflow: auto; }

body {
  font-family: var(--nr-font);
  color: var(--nr-text);
  background: var(--nr-white);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }

/* ── Typography ── */
h1, h2, h3, h4 { line-height: 1.2; letter-spacing: -0.02em; }
h1 { font-size: clamp(2.2rem, 5vw, 3.6rem); font-weight: 800; }
h2 { font-size: clamp(1.5rem, 3vw, 2.2rem); font-weight: 700; }
h3 { font-size: 1.1rem; font-weight: 700; }
h4 { font-size: 0.95rem; font-weight: 700; }
p { color: var(--nr-muted); }

/* ── Layout ── */
.nr-container { max-width: 1080px; margin: 0 auto; padding: 0 2rem; }
.nr-container-sm { max-width: 760px; margin: 0 auto; padding: 0 2rem; }
.nr-section { padding: 5rem 0; }
.nr-section-alt { background: var(--nr-off); padding: 5rem 0; }

/* ── Nav ── */
.nr-nav {
  position: sticky; top: 0; z-index: 200;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--nr-border);
  height: 64px;
}
.nr-nav-inner {
  max-width: 1080px; margin: 0 auto; padding: 0 2rem;
  height: 100%; display: flex; align-items: center; justify-content: space-between;
}
.nr-nav-logo {
  display: flex; align-items: center; gap: 10px;
  font-weight: 800; font-size: 1.05rem; color: var(--nr-dark);
  text-decoration: none; flex-shrink: 0;
}
.nr-nav-logo img { width: 36px; height: 36px; object-fit: contain; flex-shrink: 0; }
.nr-nav-links {
  display: flex; align-items: center; gap: 0.25rem;
  font-size: 0.88rem;
}
.nr-nav-links a {
  color: var(--nr-muted); padding: 0.4rem 0.75rem; border-radius: var(--nr-radius-sm);
  transition: color 0.15s, background 0.15s; white-space: nowrap;
}
.nr-nav-links a:hover { color: var(--nr-dark); background: var(--nr-off); }
.nr-nav-links a.active { color: var(--nr-dark); font-weight: 600; }
.nr-nav-cta {
  background: var(--nr-dark) !important; color: var(--nr-white) !important;
  padding: 0.45rem 1.1rem !important; border-radius: var(--nr-radius-sm) !important;
  font-weight: 600 !important; font-size: 0.85rem !important;
  transition: background 0.15s !important;
}
.nr-nav-cta:hover { background: #2d2d4e !important; }

/* ── Buttons ── */
.btn {
  display: inline-flex; align-items: center; gap: 0.4rem;
  padding: 0.75rem 1.6rem; border-radius: var(--nr-radius-sm);
  font-weight: 600; font-size: 0.9rem; transition: all 0.15s; cursor: pointer;
  text-decoration: none; border: none;
}
.btn-primary { background: var(--nr-dark); color: var(--nr-white); }
.btn-primary:hover { background: #2d2d4e; transform: translateY(-1px); box-shadow: var(--nr-shadow); }
.btn-outline { border: 1.5px solid var(--nr-border); color: var(--nr-text); background: transparent; }
.btn-outline:hover { border-color: var(--nr-dark); background: var(--nr-off); }
.btn-teal { background: var(--nr-teal); color: var(--nr-dark); }
.btn-teal:hover { background: #5eead4; }

/* ── Badge ── */
.nr-badge {
  display: inline-block; font-size: 0.72rem; font-weight: 700;
  letter-spacing: 0.06em; text-transform: uppercase;
  padding: 0.3rem 0.8rem; border-radius: 20px;
}
.nr-badge-live { background: #dcfce7; color: #166534; }
.nr-badge-draft { background: #fef3c7; color: #92400e; }
.nr-badge-version { background: var(--nr-off); color: var(--nr-muted); border: 1px solid var(--nr-border); }

/* ── Cards ── */
.nr-card {
  background: var(--nr-white); border: 1px solid var(--nr-border);
  border-radius: var(--nr-radius); padding: 1.75rem;
  transition: box-shadow 0.2s, transform 0.2s;
}
.nr-card:hover { box-shadow: var(--nr-shadow); transform: translateY(-2px); }
.nr-card-dark { background: var(--nr-dark); color: var(--nr-white); border: none; }
.nr-card-dark p { color: #9ca3af; }

/* ── Grid ── */
.nr-grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1.5rem; }
.nr-grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; }
.nr-grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.25rem; }
@media (max-width: 900px) {
  .nr-grid-3 { grid-template-columns: repeat(2, 1fr); }
  .nr-grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 600px) {
  .nr-grid-2, .nr-grid-3, .nr-grid-4 { grid-template-columns: 1fr; }
  .nr-nav-links { display: none; }
  .nr-container, .nr-container-sm { padding: 0 1.25rem; }
  .nr-section, .nr-section-alt { padding: 3.5rem 0; }
}

/* ── Divider ── */
.nr-divider { border: none; border-top: 1px solid var(--nr-border); }

/* ── Section label ── */
.nr-eyebrow {
  font-size: 0.72rem; font-weight: 700; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--nr-teal-dim); margin-bottom: 0.75rem;
}

/* ── Tag ── */
.nr-tag {
  display: inline-block; font-size: 0.75rem; font-weight: 700;
  padding: 0.2rem 0.65rem; border-radius: 4px;
  background: var(--nr-off); color: var(--nr-text); border: 1px solid var(--nr-border);
}
.nr-tag-teal { background: #ccfbf1; color: var(--nr-teal-dim); border-color: #99f6e4; }
.nr-tag-dark { background: var(--nr-dark); color: var(--nr-white); border-color: var(--nr-dark); }

/* ── Step indicator ── */
.nr-step-num {
  width: 40px; height: 40px; border-radius: 50%;
  background: var(--nr-dark); color: var(--nr-white);
  display: flex; align-items: center; justify-content: center;
  font-weight: 800; font-size: 0.9rem; flex-shrink: 0;
}

/* ── Stat ── */
.nr-stat-num { font-size: 2.5rem; font-weight: 800; color: var(--nr-dark); letter-spacing: -0.04em; }
.nr-stat-label { font-size: 0.85rem; color: var(--nr-muted); }

/* ── Accordion / FAQ ── */
.nr-accordion { border: 1px solid var(--nr-border); border-radius: var(--nr-radius); overflow: hidden; }
.nr-accordion-item { border-bottom: 1px solid var(--nr-border); }
.nr-accordion-item:last-child { border-bottom: none; }
.nr-accordion-trigger {
  width: 100%; text-align: left; padding: 1.25rem 1.5rem;
  background: none; border: none; cursor: pointer;
  font-family: var(--nr-font); font-size: 0.95rem; font-weight: 600;
  color: var(--nr-text); display: flex; justify-content: space-between; align-items: center;
  transition: background 0.15s;
}
.nr-accordion-trigger:hover { background: var(--nr-off); }
.nr-accordion-trigger .icon { font-size: 1.2rem; color: var(--nr-muted); transition: transform 0.2s; flex-shrink: 0; }
.nr-accordion-trigger[aria-expanded="true"] .icon { transform: rotate(45deg); }
.nr-accordion-body { display: none; padding: 0 1.5rem 1.25rem; }
.nr-accordion-body p { font-size: 0.9rem; }
.nr-accordion-trigger[aria-expanded="true"] + .nr-accordion-body { display: block; }

/* ── Table ── */
.nr-table { width: 100%; border-collapse: collapse; font-size: 0.9rem; }
.nr-table th {
  text-align: left; padding: 0.75rem 1rem;
  background: var(--nr-dark); color: var(--nr-white); font-weight: 600;
}
.nr-table th:first-child { border-radius: 8px 0 0 0; }
.nr-table th:last-child { border-radius: 0 8px 0 0; }
.nr-table td { padding: 0.85rem 1rem; border-bottom: 1px solid var(--nr-border); vertical-align: top; color: var(--nr-muted); }
.nr-table td:first-child { color: var(--nr-text); font-weight: 600; }
.nr-table tr:last-child td { border-bottom: none; }
.nr-table tr:hover td { background: var(--nr-off); }

/* ── Code ── */
.nr-code {
  background: var(--nr-dark); color: #e2e8f0;
  border-radius: var(--nr-radius); padding: 1.5rem;
  font-family: var(--nr-mono); font-size: 0.85rem; line-height: 1.7;
  overflow-x: auto;
}
.nr-code .key { color: var(--nr-teal); }
.nr-code .val { color: #fbbf24; }
.nr-code .comment { color: #6b7280; }

/* ── Footer ── */
.nr-footer {
  border-top: 1px solid var(--nr-border);
  padding: 3rem 0 2rem;
  font-size: 0.82rem; color: var(--nr-muted);
}
.nr-footer-inner {
  max-width: 1080px; margin: 0 auto; padding: 0 2rem;
  display: grid; grid-template-columns: 1fr auto; gap: 2rem; align-items: start;
}
.nr-footer-logo { font-weight: 800; font-size: 1rem; color: var(--nr-dark); margin-bottom: 0.5rem; }
.nr-footer-links { display: flex; gap: 1.5rem; flex-wrap: wrap; }
.nr-footer-links a { color: var(--nr-muted); transition: color 0.15s; }
.nr-footer-links a:hover { color: var(--nr-dark); }
@media (max-width: 600px) {
  .nr-footer-inner { grid-template-columns: 1fr; }
}

/* ── Dot status ── */
.nr-dot { width: 8px; height: 8px; border-radius: 50%; display: inline-block; flex-shrink: 0; }
.nr-dot-live { background: #22c55e; }
.nr-dot-draft { background: #f59e0b; }
.nr-dot-soon { background: #94a3b8; }

/* ── Highlight bar ── */
.nr-highlight-bar { border-left: 3px solid var(--nr-teal); padding: 0.75rem 1.25rem; background: #f0fdfa; border-radius: 0 8px 8px 0; }
.nr-highlight-bar p { color: var(--nr-text); font-size: 0.9rem; }

/* ── Problem item ── */
.nr-problem-item { border-left: 3px solid var(--nr-dark); padding: 1rem 1.25rem; background: var(--nr-white); border-radius: 0 8px 8px 0; }
.nr-problem-item h4 { margin-bottom: 0.3rem; }
.nr-problem-item p { font-size: 0.85rem; }

/* ── Animated counter placeholder ── */
.nr-counter-row { display: flex; gap: 3rem; flex-wrap: wrap; }