/* ============================================
   IO Technologies — Design System
   ============================================ */

:root {
  --bg: #FBFAF7;
  --bg-2: #F4F0E8;
  --ink: #1A1714;
  --ink-2: #2A2520;
  --muted: #6B655F;
  --muted-2: #8C857C;
  --line: #E8E2D7;
  --line-2: #D8D0C2;
  --accent: #C6452B;
  --accent-soft: #E5A693;
  --max: 1180px;
  --radius: 14px;
  --radius-sm: 8px;
}

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

html { scroll-behavior: smooth; }

/* anchor offsets behind sticky nav */
section[id], header[id], #main, #platform-data { scroll-margin-top: 88px; }

body {
  background: var(--bg);
  color: var(--ink);
  font-family: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

.serif {
  font-family: 'Instrument Serif', 'Iowan Old Style', Georgia, serif;
  font-weight: 400;
  letter-spacing: -0.01em;
}

.mono {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.78rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--muted);
}

a { color: var(--ink); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--accent); }

/* ── focus visibility (WCAG 2.2 AA) ── */
:focus { outline: none; }
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ── skip link ── */
.skip-link {
  position: absolute;
  left: 16px;
  top: -56px;
  background: var(--ink);
  color: var(--bg);
  padding: 12px 18px;
  border-radius: 8px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.82rem;
  z-index: 200;
  transition: top 200ms ease;
}
.skip-link:focus,
.skip-link:focus-visible {
  top: 16px;
  color: var(--bg);
  outline-offset: 4px;
}

.container {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 32px;
}

/* ============================================
   NAV
   ============================================ */
nav.top {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(251, 250, 247, 0.85);
  backdrop-filter: saturate(1.4) blur(12px);
  -webkit-backdrop-filter: saturate(1.4) blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 32px;
  max-width: var(--max);
  margin: 0 auto;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: 'Instrument Serif', serif;
  font-size: 1.3rem;
  letter-spacing: -0.01em;
}
.brand-mark {
  width: 22px;
  height: 22px;
  background: var(--ink);
  border-radius: 5px;
  position: relative;
}
.brand-mark::after {
  content: '';
  position: absolute;
  inset: 5px;
  background: var(--accent);
  border-radius: 2px;
}
.nav-links {
  display: flex;
  gap: 36px;
  font-size: 0.92rem;
  color: var(--muted);
}
.nav-links a:hover { color: var(--ink); }

/* ============================================
   HERO
   ============================================ */
.hero {
  padding: 110px 0 90px;
  position: relative;
  overflow: hidden;
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 60px;
  align-items: center;
}
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 6px 12px;
  border: 1px solid var(--line-2);
  border-radius: 100px;
  background: var(--bg);
  margin-bottom: 28px;
}
.eyebrow .dot {
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
  animation: pulse 2.4s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}
h1.display {
  font-family: 'Instrument Serif', serif;
  font-size: clamp(2.6rem, 6vw, 4.6rem);
  line-height: 1.02;
  letter-spacing: -0.025em;
  margin-bottom: 28px;
}
h1.display em {
  font-style: italic;
  color: var(--accent);
}
.lead {
  font-size: 1.18rem;
  color: var(--ink-2);
  max-width: 540px;
  line-height: 1.55;
  margin-bottom: 36px;
}
.cta-row { display: flex; gap: 14px; flex-wrap: wrap; }
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 22px;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 500;
  transition: all 0.2s;
  border: 1px solid transparent;
  cursor: pointer;
}
.btn-primary { background: var(--ink); color: var(--bg); }
.btn-primary:hover { background: var(--accent); color: var(--bg); }
.btn-ghost { border-color: var(--line-2); color: var(--ink); background: transparent; }
.btn-ghost:hover { background: var(--ink); color: var(--bg); border-color: var(--ink); }
.btn-sm { padding: 8px 16px; font-size: 0.88rem; }

/* Hero product mockup */
.mockup {
  background: var(--ink);
  border-radius: var(--radius);
  padding: 14px;
  box-shadow: 0 30px 60px -20px rgba(26, 23, 20, 0.25),
              0 12px 30px -8px rgba(26, 23, 20, 0.15);
  position: relative;
}
.mockup-bar {
  display: flex;
  gap: 6px;
  padding: 4px 8px 12px;
}
.mockup-bar span {
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: #3a342f;
}
.mockup-window {
  background: var(--bg);
  border-radius: 10px;
  overflow: hidden;
  display: grid;
  grid-template-columns: 130px 1fr;
  min-height: 380px;
}
.mockup-sidebar {
  background: var(--bg-2);
  padding: 16px 12px;
  border-right: 1px solid var(--line);
}
.mockup-channel {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 6px;
  border-radius: 6px;
  font-size: 0.78rem;
  color: var(--ink-2);
  margin-bottom: 4px;
}
.mockup-channel.active { background: var(--bg); font-weight: 500; }
.mockup-channel .ic {
  width: 18px; height: 18px;
  border-radius: 4px;
  display: grid;
  place-items: center;
  font-size: 0.6rem;
  color: white;
  font-weight: 600;
}
.ic-wa { background: #25D366; }
.ic-fb { background: #1877F2; }
.ic-ig { background: linear-gradient(45deg, #F58529, #DD2A7B); }
.ic-web {
  background: var(--ink);
  font-family: 'IBM Plex Mono', monospace;
  font-weight: 500;
}

.mockup-main { padding: 16px; }
.mockup-thread { font-size: 0.78rem; }
.mockup-msg {
  background: var(--bg-2);
  padding: 10px 12px;
  border-radius: 10px;
  margin-bottom: 10px;
  max-width: 75%;
}
.mockup-msg.mine {
  background: var(--ink);
  color: var(--bg);
  margin-left: auto;
}
.mockup-ai {
  margin-top: 14px;
  padding: 12px;
  border: 1px dashed var(--line-2);
  border-radius: 8px;
  background: var(--bg);
}
.mockup-ai-label {
  font-size: 0.65rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  margin-bottom: 6px;
  font-weight: 600;
}
.mockup-ai p { font-size: 0.78rem; color: var(--ink-2); }

/* ============================================
   SECTION
   ============================================ */
section {
  padding: 100px 0;
  border-top: 1px solid var(--line);
}
.section-head {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 60px;
  margin-bottom: 56px;
  align-items: start;
}
.section-head h2 {
  font-family: 'Instrument Serif', serif;
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.05;
  letter-spacing: -0.02em;
  font-weight: 400;
}
.section-head h2 em { font-style: italic; color: var(--accent); }
.section-head p {
  color: var(--muted);
  font-size: 1.05rem;
  max-width: 600px;
  margin-top: 14px;
}

/* Product feature cards */
.features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.feature {
  padding: 32px 28px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: all 0.3s;
}
.feature:hover {
  border-color: var(--ink);
  transform: translateY(-2px);
}
.feature-num {
  font-family: 'Instrument Serif', serif;
  font-size: 2.4rem;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 28px;
}
.feature h3 {
  font-family: 'Instrument Serif', serif;
  font-size: 1.5rem;
  font-weight: 400;
  margin-bottom: 12px;
  letter-spacing: -0.01em;
}
.feature p { color: var(--muted); font-size: 0.95rem; }

/* How it works — data flow */
.flow {
  background: var(--bg-2);
  border-radius: var(--radius);
  padding: 48px;
}
.flow-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  position: relative;
}
.flow-step {
  position: relative;
}
.flow-step::after {
  content: '→';
  position: absolute;
  right: -22px;
  top: 12px;
  color: var(--line-2);
  font-size: 1.2rem;
}
.flow-step:last-child::after { display: none; }
.flow-num {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.72rem;
  color: var(--accent);
  letter-spacing: 0.1em;
  margin-bottom: 14px;
  font-weight: 600;
}
.flow-step h4 {
  font-family: 'Instrument Serif', serif;
  font-size: 1.25rem;
  font-weight: 400;
  margin-bottom: 8px;
}
.flow-step p { font-size: 0.88rem; color: var(--muted); line-height: 1.5; }

/* Data table */
.data-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 32px;
}
.data-table th, .data-table td {
  text-align: left;
  padding: 18px 20px;
  border-bottom: 1px solid var(--line);
  font-size: 0.95rem;
  vertical-align: top;
}
.data-table th {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
  font-weight: 600;
  padding-bottom: 14px;
}
.data-table td:first-child {
  font-weight: 500;
  width: 28%;
}
.data-table td:nth-child(2) { color: var(--muted); }

/* About */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: start;
}
.about-grid p { color: var(--ink-2); font-size: 1.02rem; margin-bottom: 18px; }
.about-meta {
  background: var(--bg-2);
  border-radius: var(--radius);
  padding: 32px;
}
.about-meta dl { display: grid; grid-template-columns: 130px 1fr; gap: 16px 20px; }
.about-meta dt {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
  padding-top: 3px;
}
.about-meta dd { color: var(--ink); font-size: 0.95rem; }

/* Contact */
.contact-card {
  background: var(--ink);
  color: var(--bg);
  border-radius: var(--radius);
  padding: 60px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.contact-card h2 {
  font-family: 'Instrument Serif', serif;
  font-size: 2.6rem;
  font-weight: 400;
  line-height: 1.05;
  margin-bottom: 16px;
}
.contact-card h2 em { font-style: italic; color: var(--accent-soft); }
.contact-card p { color: rgba(251, 250, 247, 0.7); margin-bottom: 0; }
.contact-list { list-style: none; }
.contact-list li {
  padding: 18px 0;
  border-top: 1px solid rgba(251, 250, 247, 0.12);
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.contact-list li:last-child { border-bottom: 1px solid rgba(251, 250, 247, 0.12); }
.contact-list .label {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: rgba(251, 250, 247, 0.5);
}
.contact-list .value { color: var(--bg); }
.contact-list a.value:hover { color: var(--accent-soft); }
.contact-note {
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid rgba(251, 250, 247, 0.12);
  color: rgba(251, 250, 247, 0.55);
  font-size: 0.82rem;
  line-height: 1.55;
}
.contact-note em {
  font-family: 'IBM Plex Mono', monospace;
  font-style: normal;
  font-size: 0.78rem;
  color: var(--accent-soft);
  background: rgba(251, 250, 247, 0.06);
  padding: 1px 6px;
  border-radius: 4px;
}

/* Footer */
footer {
  border-top: 1px solid var(--line);
  padding: 60px 0 40px;
  margin-top: 40px;
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 40px;
  flex-wrap: wrap;
}
.footer-brand p {
  color: var(--muted);
  font-size: 0.88rem;
  margin-top: 12px;
  max-width: 320px;
}
.footer-links {
  display: flex;
  gap: 48px;
}
.footer-col h5 {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
  margin-bottom: 16px;
  font-weight: 600;
}
.footer-col ul { list-style: none; }
.footer-col li { font-size: 0.92rem; }
.footer-col li a {
  display: inline-block;
  padding: 8px 0;
  min-height: 44px;
  line-height: 1.6;
  color: var(--ink-2);
}
.footer-col a:hover { color: var(--accent); }
.footer-bottom {
  margin-top: 50px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  font-size: 0.82rem;
  color: var(--muted);
  flex-wrap: wrap;
  gap: 16px;
}

/* ============================================
   LEGAL PAGES
   ============================================ */
.legal-hero {
  padding: 80px 0 40px;
}
.legal-hero .mono { margin-bottom: 14px; display: block; }
.legal-hero h1 {
  font-family: 'Instrument Serif', serif;
  font-size: clamp(2.4rem, 5vw, 3.6rem);
  font-weight: 400;
  letter-spacing: -0.02em;
  line-height: 1.05;
  margin-bottom: 16px;
}
.legal-hero .lead { font-size: 1.08rem; max-width: 720px; }
.legal-body {
  padding: 40px 0 100px;
  max-width: 760px;
  margin: 0 auto;
}
.legal-body h2 {
  font-family: 'Instrument Serif', serif;
  font-size: 1.7rem;
  font-weight: 400;
  letter-spacing: -0.01em;
  margin-top: 56px;
  margin-bottom: 18px;
}
.legal-body h3 {
  font-family: 'IBM Plex Sans', sans-serif;
  font-size: 1.05rem;
  font-weight: 600;
  margin-top: 32px;
  margin-bottom: 10px;
}
.legal-body p {
  color: var(--ink-2);
  margin-bottom: 16px;
  font-size: 1rem;
  line-height: 1.7;
}
.legal-body ul, .legal-body ol {
  margin: 0 0 18px 22px;
  color: var(--ink-2);
}
.legal-body li { margin-bottom: 8px; line-height: 1.6; }
.legal-body strong { color: var(--ink); font-weight: 600; }
.legal-body a { color: var(--accent); text-decoration: underline; text-underline-offset: 3px; }

.toc {
  background: var(--bg-2);
  border-radius: var(--radius);
  padding: 28px 32px;
  margin: 28px 0 40px;
}
.toc h4 {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
  margin-bottom: 14px;
  font-weight: 600;
}
.toc ol {
  margin: 0;
  padding-left: 24px;
  columns: 2;
  column-gap: 32px;
}
.toc li { font-size: 0.92rem; margin-bottom: 6px; }

/* ============================================
   RESPONSIVE
   ============================================ */
@media (max-width: 900px) {
  .container { padding: 0 22px; }
  .nav-inner { padding: 16px 22px; }
  .nav-links { gap: 22px; font-size: 0.85rem; }
  .nav-links a:not(.btn) { display: none; }
  .nav-links .btn { display: inline-flex; }
  .hero { padding: 70px 0 60px; }
  .hero-grid { grid-template-columns: 1fr; gap: 50px; }
  .section-head { grid-template-columns: 1fr; gap: 16px; margin-bottom: 40px; }
  .features { grid-template-columns: 1fr; }
  .flow { padding: 32px 24px; }
  .flow-steps { grid-template-columns: 1fr; gap: 32px; }
  .flow-step::after { display: none; }
  .about-grid { grid-template-columns: 1fr; gap: 32px; }
  .contact-card { grid-template-columns: 1fr; padding: 40px 28px; gap: 32px; }
  section { padding: 70px 0; }
  .footer-links { gap: 32px; flex-wrap: wrap; }
  .toc ol { columns: 1; }
}

/* ============================================
   SECTION-HEAD MODIFIERS
   ============================================ */
.section-head--platform { margin-top: 80px; }
@media (max-width: 900px) { .section-head--platform { margin-top: 56px; } }

/* ============================================
   REVEAL ON SCROLL (subtle)
   ============================================ */
.reveal {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 700ms ease, transform 700ms cubic-bezier(0.2, 0.8, 0.2, 1);
  will-change: opacity, transform;
}
.reveal.in {
  opacity: 1;
  transform: translateY(0);
}

/* Reduced-motion: kill all animations + transitions */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  .reveal { opacity: 1; transform: none; }
  .eyebrow .dot { animation: none; opacity: 1; }
}