/* ==========================================================================
   CHALKLINE — Industrial Field Instrument & Blueprint Design System
   Aesthetic: Cured Asphalt Slate + Safety Amber + Snap-Line Blue + Survey Grid
   WCAG AAA High-Contrast | Zero External JS Dependencies | Print-Ready Legal
   ========================================================================== */

:root {
  --bg-asphalt: #0d0f12;
  --bg-panel: #14181e;
  --bg-panel-elevated: #1b2028;
  --bg-paper: #f8fafc;
  --ink-primary: #f8fafc;
  --ink-secondary: #cbd5e1;
  --ink-muted: #94a3b8;
  --ink-dark: #0f172a;
  --chalk-amber: #f59e0b;
  --chalk-amber-bright: #fbbf24;
  --chalk-amber-dim: rgba(245, 158, 11, 0.14);
  --snap-blue: #38bdf8;
  --snap-blue-dim: rgba(56, 189, 248, 0.14);
  --jobsite-green: #22c55e;
  --jobsite-green-bg: rgba(34, 197, 94, 0.12);
  --cutout-crimson: #ef4444;
  --border-subtle: #262d37;
  --border-strong: #3b4454;
  --font-display: 'Barlow Condensed', 'Arial Narrow', 'Impact', sans-serif;
  --font-body: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'IBM Plex Mono', ui-monospace, 'SFMono-Regular', Menlo, monospace;
  --max-w: 1160px;
  --legal-w: 860px;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
}

*, *::before, *::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  background-color: var(--bg-asphalt);
  color: var(--ink-primary);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background-color: var(--bg-asphalt);
  background-image:
    linear-gradient(to right, rgba(148, 163, 184, 0.045) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(148, 163, 184, 0.045) 1px, transparent 1px),
    linear-gradient(to right, rgba(56, 189, 248, 0.07) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(56, 189, 248, 0.07) 1px, transparent 1px);
  background-size: 24px 24px, 24px 24px, 120px 120px, 120px 120px;
  background-position: -1px -1px;
}

a {
  color: var(--chalk-amber-bright);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: color 0.16s ease, background-color 0.16s ease;
}

a:hover, a:focus-visible {
  color: #ffffff;
}

a:focus-visible, button:focus-visible {
  outline: 2px solid var(--chalk-amber);
  outline-offset: 3px;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 8px;
  z-index: 100;
  padding: 10px 16px;
  background: var(--chalk-amber);
  color: var(--bg-asphalt);
  font-weight: 700;
  border-radius: var(--radius-sm);
  text-decoration: none;
}

.skip-link:focus {
  left: 12px;
}

/* Top Instrument Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(13, 15, 18, 0.94);
  backdrop-filter: blur(10px);
  border-bottom: 2px solid var(--border-strong);
}

.header-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.brand-lockup {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--ink-primary);
  min-height: 48px;
}

.brand-mark {
  width: 40px;
  height: 40px;
  flex-shrink: 0;
}

.brand-wordmark {
  display: flex;
  flex-direction: column;
  line-height: 1.05;
}

.brand-name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.55rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--ink-primary);
}

.brand-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--chalk-amber);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

.nav-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.84rem;
  font-weight: 500;
  color: var(--ink-secondary);
  text-decoration: none;
  border: 1px solid transparent;
}

.nav-link:hover {
  color: var(--ink-primary);
  background: var(--bg-panel-elevated);
  border-color: var(--border-strong);
}

.nav-link[aria-current="page"] {
  color: var(--bg-asphalt);
  background: var(--chalk-amber);
  border-color: var(--chalk-amber);
  font-weight: 600;
}

/* Chalk-Line Snap Divider */
.chalk-snap-rule {
  height: 3px;
  width: 100%;
  background: linear-gradient(90deg, var(--chalk-amber) 0%, var(--snap-blue) 55%, rgba(56, 189, 248, 0.15) 100%);
  transform-origin: left center;
  animation: snapReveal 0.55s cubic-bezier(0.16, 1, 0.3, 1) both;
}

@keyframes snapReveal {
  from { transform: scaleX(0); opacity: 0.4; }
  to { transform: scaleX(1); opacity: 1; }
}

@media (prefers-reduced-motion: reduce) {
  .chalk-snap-rule { animation: none; }
  html { scroll-behavior: auto; }
}

/* Layout Containers */
.container {
  width: 100%;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 20px;
}

.legal-container {
  width: 100%;
  max-width: var(--legal-w);
  margin: 0 auto;
  padding: 44px 20px 72px;
}

main {
  flex: 1;
}

/* Hero Section */
.hero {
  padding: 56px 0 48px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.12fr 0.88fr;
  gap: 36px;
  align-items: start;
}

.eyebrow-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--chalk-amber-dim);
  border: 1px solid rgba(245, 158, 11, 0.45);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--chalk-amber-bright);
  margin-bottom: 18px;
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.6rem, 5.2vw, 4.25rem);
  font-weight: 800;
  line-height: 0.98;
  letter-spacing: 0.01em;
  text-transform: uppercase;
  margin: 0 0 18px;
  color: var(--ink-primary);
}

.hero h1 .accent {
  color: var(--chalk-amber);
}

.hero-lead {
  font-size: 1.14rem;
  color: var(--ink-secondary);
  margin: 0 0 26px;
  max-width: 60ch;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 24px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 52px;
  padding: 12px 22px;
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: 0.98rem;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
  border: 2px solid transparent;
  transition: transform 0.12s ease, background-color 0.15s ease, border-color 0.15s ease;
}

.btn:active {
  transform: translateY(1px);
}

.btn-primary {
  background: var(--chalk-amber);
  color: #0b0d10;
  border-color: var(--chalk-amber);
}

.btn-primary:hover {
  background: var(--chalk-amber-bright);
  border-color: var(--chalk-amber-bright);
  color: #0b0d10;
}

.btn-secondary {
  background: var(--bg-panel-elevated);
  color: var(--ink-primary);
  border-color: var(--border-strong);
}

.btn-secondary:hover {
  border-color: var(--snap-blue);
  color: #ffffff;
}

.guarantee-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
  padding: 14px 16px;
  background: var(--jobsite-green-bg);
  border: 1.5px solid rgba(34, 197, 94, 0.5);
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  font-weight: 600;
  color: #dcfce7;
}

.guarantee-strip span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

/* Field Instrument Preview Card */
.instrument-card {
  background: var(--bg-panel);
  border: 2px solid var(--border-strong);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: 0 24px 48px rgba(0, 0, 0, 0.55);
}

.instrument-topbar {
  background: #090b0e;
  padding: 14px 18px;
  border-bottom: 1.5px solid var(--border-strong);
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
}

.readout-main {
  font-family: var(--font-mono);
  font-size: 1.85rem;
  font-weight: 700;
  color: var(--chalk-amber);
  font-variant-numeric: tabular-nums;
}

.readout-sub {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--ink-secondary);
  font-variant-numeric: tabular-nums;
}

.trade-tabs {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 6px;
  padding: 12px 16px;
  background: var(--bg-panel-elevated);
  border-bottom: 1px solid var(--border-subtle);
}

.trade-tab {
  min-height: 44px;
  padding: 6px 8px;
  border-radius: var(--radius-sm);
  border: 1.5px solid var(--border-strong);
  background: var(--bg-asphalt);
  color: var(--ink-secondary);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
}

.trade-tab[aria-pressed="true"] {
  background: var(--chalk-amber);
  border-color: var(--chalk-amber);
  color: #0b0d10;
}

.diagram-viewport {
  position: relative;
  padding: 18px;
  background:
    radial-gradient(circle at 70% 30%, rgba(56, 189, 248, 0.12), transparent 60%),
    #10151c;
  border-bottom: 1.5px solid var(--border-subtle);
}

.pdf-mini-sheet {
  padding: 16px 18px;
  background: var(--bg-paper);
  color: var(--ink-dark);
}

.pdf-mini-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 2px solid #cbd5e1;
  padding-bottom: 8px;
  margin-bottom: 10px;
}

.pdf-mini-header strong {
  font-family: var(--font-display);
  font-size: 1.15rem;
  letter-spacing: 0.03em;
  text-transform: uppercase;
}

.pdf-badge {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 4px;
  background: #dbeafe;
  color: #1e3a8a;
}

.pdf-line-row {
  display: flex;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  padding: 4px 0;
  border-bottom: 1px dashed #cbd5e1;
  color: #1e293b;
  font-variant-numeric: tabular-nums;
}

.pdf-sig-box {
  margin-top: 10px;
  padding: 8px 10px;
  background: #f1f5f9;
  border: 1px solid #94a3b8;
  border-radius: 6px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: #0f172a;
}

/* Section Grid & Feature Blocks */
.section {
  padding: 52px 0;
  border-top: 1px solid var(--border-subtle);
}

.section-header {
  margin-bottom: 32px;
}

.section-kicker {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--snap-blue);
  display: block;
  margin-bottom: 6px;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 3.6vw, 2.75rem);
  font-weight: 800;
  text-transform: uppercase;
  margin: 0;
  line-height: 1.05;
}

.card-grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.card-grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
}

.spec-card {
  background: var(--bg-panel);
  border: 1.5px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 22px;
}

.spec-card h3 {
  font-family: var(--font-display);
  font-size: 1.38rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.02em;
  margin: 0 0 8px;
  color: var(--ink-primary);
}

.spec-card p {
  margin: 0;
  color: var(--ink-secondary);
  font-size: 0.96rem;
}

.spec-code {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--chalk-amber);
  background: var(--chalk-amber-dim);
  padding: 2px 8px;
  border-radius: 4px;
  margin-bottom: 10px;
}

/* Pricing & Fair Terms Table */
.plan-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.plan-card {
  background: var(--bg-panel);
  border: 1.5px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  flex-direction: column;
}

.plan-card.featured {
  border: 2px solid var(--chalk-amber);
  background: linear-gradient(180deg, rgba(245, 158, 11, 0.08) 0%, var(--bg-panel) 45%);
}

.plan-price {
  font-family: var(--font-mono);
  font-size: 1.9rem;
  font-weight: 700;
  color: var(--ink-primary);
  margin: 8px 0 4px;
  font-variant-numeric: tabular-nums;
}

.plan-sub {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--ink-muted);
  margin-bottom: 16px;
}

.plan-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 8px;
  font-size: 0.94rem;
  color: var(--ink-secondary);
}

.plan-list li::before {
  content: "✓ ";
  color: var(--jobsite-green);
  font-weight: 700;
}

/* Legal & Support Document Typography */
.doc-header {
  padding-bottom: 24px;
  margin-bottom: 32px;
  border-bottom: 2px solid var(--border-strong);
}

.doc-header h1 {
  font-family: var(--font-display);
  font-size: clamp(2.2rem, 4.5vw, 3.2rem);
  font-weight: 800;
  text-transform: uppercase;
  line-height: 1.02;
  margin: 8px 0 12px;
}

.doc-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 20px;
  font-family: var(--font-mono);
  font-size: 0.83rem;
  color: var(--ink-muted);
}

.summary-callout {
  background: var(--bg-panel);
  border-left: 4px solid var(--chalk-amber);
  border-top: 1px solid var(--border-strong);
  border-right: 1px solid var(--border-strong);
  border-bottom: 1px solid var(--border-strong);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 18px 22px;
  margin-bottom: 32px;
}

.summary-callout strong {
  color: var(--chalk-amber-bright);
}

.legal-section {
  margin-bottom: 34px;
}

.legal-section h2 {
  font-family: var(--font-display);
  font-size: 1.55rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.02em;
  color: var(--ink-primary);
  margin: 0 0 12px;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--border-subtle);
}

.legal-section h3 {
  font-size: 1.06rem;
  font-weight: 700;
  color: var(--chalk-amber-bright);
  margin: 18px 0 8px;
}

.legal-section p, .legal-section li {
  color: var(--ink-secondary);
  font-size: 0.98rem;
}

.legal-section ul {
  padding-left: 20px;
  display: grid;
  gap: 8px;
}

.data-table-wrap {
  overflow-x: auto;
  margin: 16px 0;
  border: 1.5px solid var(--border-strong);
  border-radius: var(--radius-md);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-panel);
  font-size: 0.9rem;
}

.data-table th, .data-table td {
  text-align: left;
  padding: 12px 14px;
  border-bottom: 1px solid var(--border-subtle);
  vertical-align: top;
}

.data-table th {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--chalk-amber-bright);
  background: #0f1318;
}

.data-table tr:last-child td {
  border-bottom: none;
}

code {
  font-family: var(--font-mono);
  font-size: 0.86em;
  background: var(--bg-panel-elevated);
  border: 1px solid var(--border-subtle);
  padding: 1px 6px;
  border-radius: 4px;
  color: #e2e8f0;
}

/* FAQ Accordion Details */
details.faq-item {
  background: var(--bg-panel);
  border: 1.5px solid var(--border-strong);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
  padding: 4px 18px;
}

details.faq-item summary {
  min-height: 52px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  font-weight: 700;
  color: var(--ink-primary);
  list-style: none;
  padding: 10px 0;
}

details.faq-item summary::-webkit-details-marker {
  display: none;
}

details.faq-item summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 1.25rem;
  color: var(--chalk-amber);
  margin-left: 12px;
}

details.faq-item[open] summary::after {
  content: "−";
}

details.faq-item .faq-body {
  padding: 0 0 16px;
  color: var(--ink-secondary);
  border-top: 1px solid var(--border-subtle);
  padding-top: 12px;
}

/* Footer */
.site-footer {
  border-top: 2px solid var(--border-strong);
  background: #090b0e;
  padding: 36px 0;
  margin-top: auto;
}

.footer-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}

.footer-links {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
  font-family: var(--font-mono);
  font-size: 0.84rem;
}

.footer-copy {
  font-size: 0.86rem;
  color: var(--ink-muted);
}

/* Responsive */
@media (max-width: 920px) {
  .hero-grid, .card-grid-3, .plan-grid, .card-grid-2 {
    grid-template-columns: 1fr;
  }
  .hero {
    padding: 36px 0 32px;
  }
}

/* Print-Clean Styles for Legal Compliance Review */
@media print {
  body {
    background: #ffffff !important;
    color: #000000 !important;
  }
  .site-header, .site-footer, .skip-link, .chalk-snap-rule {
    display: none !important;
  }
  .legal-section p, .legal-section li, .legal-section h2, .doc-header h1, .data-table td, .data-table th {
    color: #000000 !important;
  }
  .summary-callout, .spec-card, .data-table {
    background: #ffffff !important;
    border-color: #64748b !important;
  }
}