/* StructaLink Group — pairing board
   Palette from the mark: brass gold #C8A060 on ink #303038, paper white. */

:root {
  --gold:        #C8A060;
  --gold-deep:   #A88848;
  --gold-soft:   #E0D0B0;
  --ink:         #303038;
  --ink-deep:    #1C1C24;
  --ink-2:       #3A3844;
  --ink-lift:    #4A4854;
  --paper:       #F6F4EE;
  --paper-2:     #EDE8DC;
  --white:       #FBFAF6;
  --line:        #D8D0C0;
  --line-strong: #C8A060;
  --text:        #303038;
  --muted:       #5A5864;
  --on-dark:     #F7F4EC;
  --on-dark-dim: #D8D0C0;
  --ease:        cubic-bezier(.22, .61, .36, 1);
  --maxw:        1120px;
  --header-h:    72px;
  --display:     "Teko", "Arial Narrow", system-ui, sans-serif;
  --body:        "Lora", Georgia, "Times New Roman", serif;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

html, body { overflow-x: hidden; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--text);
  font-family: var(--body);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, .brand-name, .eyebrow, .col-label, .plate-no, .method-mark,
.filter-chip, .nav, .btn, .stage-caption, .match-readout, cite, .faq-q {
  font-family: var(--display);
  letter-spacing: 0.04em;
  line-height: 1.08;
  margin: 0;
  font-weight: 600;
  text-transform: uppercase;
}

h1 { font-size: clamp(2.8rem, 7vw, 5.4rem); font-weight: 700; letter-spacing: 0.02em; }
h2 { font-size: clamp(2rem, 4.2vw, 3.2rem); font-weight: 600; }
h3 { font-size: 1.45rem; letter-spacing: 0.06em; }

p { margin: 0; }
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
button { font: inherit; color: inherit; }
ul { margin: 0; padding: 0; list-style: none; }

.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}

.gold { color: var(--gold); }

.skip-link {
  position: absolute; left: -999px; top: 0; z-index: 400;
  background: var(--gold); color: var(--ink-deep);
  padding: 10px 16px; font-weight: 700;
}
.skip-link:focus { left: 0; }

.eyebrow {
  color: var(--gold-deep);
  font-size: 0.95rem;
  letter-spacing: 0.22em;
  margin-bottom: 12px;
}

.lead {
  max-width: 54ch;
  color: var(--muted);
  font-size: 1.05rem;
}

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 12px 22px;
  border-radius: 2px;
  font-size: 1.05rem;
  letter-spacing: 0.14em;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform .25s var(--ease), box-shadow .25s var(--ease),
    background .25s var(--ease), color .25s var(--ease), border-color .25s var(--ease);
}
.btn-primary {
  background: var(--gold);
  color: var(--ink-deep);
  box-shadow: 0 10px 24px -12px rgba(168, 136, 72, .55);
}
.btn-ghost {
  background: transparent;
  color: var(--on-dark);
  border-color: var(--on-dark-dim);
}

/* Header */
.site-header {
  position: fixed; inset: 0 0 auto 0; z-index: 100;
  height: var(--header-h);
  transition: background .3s var(--ease), border-color .3s var(--ease), backdrop-filter .3s var(--ease);
  border-bottom: 1px solid transparent;
}
.site-header.scrolled {
  background: rgba(246, 244, 238, .94);
  backdrop-filter: saturate(140%) blur(12px);
  border-bottom-color: var(--line);
}
.header-inner {
  height: 100%;
  display: flex; align-items: center; justify-content: space-between;
  gap: 16px;
}
.brand { display: inline-flex; align-items: center; gap: 11px; color: var(--ink); }
.brand img {
  width: 42px; height: 42px;
  border: 1px solid var(--line);
  background: var(--white);
}
.brand-name { font-size: 1.45rem; letter-spacing: 0.18em; font-weight: 600; }

.nav { display: flex; align-items: center; gap: 26px; }
.nav a {
  font-size: 1.05rem;
  letter-spacing: 0.14em;
  color: var(--muted);
  transition: color .2s var(--ease);
}
.nav .nav-cta {
  color: var(--ink);
  border: 1px solid var(--ink);
  padding: 8px 14px;
  letter-spacing: 0.16em;
}

.nav-toggle {
  display: none; flex-direction: column; gap: 5px;
  background: none; border: 0; cursor: pointer; padding: 8px;
}
.nav-toggle span {
  width: 22px; height: 2px; background: var(--ink); border-radius: 1px;
  transition: transform .3s var(--ease), opacity .3s var(--ease);
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* Hero */
.hero {
  position: relative;
  background: var(--ink-deep);
  color: var(--on-dark);
  min-height: 100vh;
  padding: calc(var(--header-h) + 48px) 0 72px;
  overflow: hidden;
}
.hero-grid {
  position: absolute; inset: 0; pointer-events: none;
  background-image:
    linear-gradient(rgba(200, 160, 96, 0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(200, 160, 96, 0.07) 1px, transparent 1px);
  background-size: 48px 48px;
  animation: gridDrift 28s linear infinite;
}
@keyframes gridDrift {
  from { background-position: 0 0; }
  to { background-position: 48px 48px; }
}
.hero-layout {
  position: relative;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 48px;
  align-items: center;
}
.hero-copy .eyebrow { color: var(--gold-soft); }
.hero-sub {
  margin: 22px 0 28px;
  max-width: 46ch;
  color: var(--on-dark-dim);
  font-size: 1.08rem;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }

.hero-stage { position: relative; justify-self: center; width: min(100%, 420px); }
.joint { width: 100%; height: auto; overflow: visible; }
.plate {
  fill: rgba(58, 56, 68, 0.85);
  stroke: var(--gold);
  stroke-width: 2;
}
.plate-l { animation: plateInL 1.4s var(--ease) both; }
.plate-r { animation: plateInR 1.4s var(--ease) both; }
@keyframes plateInL {
  from { transform: translateX(-28px); opacity: 0; }
  to { transform: none; opacity: 1; }
}
@keyframes plateInR {
  from { transform: translateX(28px); opacity: 0; }
  to { transform: none; opacity: 1; }
}
.maze {
  fill: none;
  stroke: var(--gold-soft);
  stroke-width: 6;
  stroke-linejoin: miter;
  stroke-dasharray: 520;
  stroke-dashoffset: 520;
  animation: mazeDraw 2.8s var(--ease) .4s forwards;
}
.maze-r { animation-delay: .7s; }
@keyframes mazeDraw {
  to { stroke-dashoffset: 0; }
}
.pin {
  fill: url(#goldBar);
  transform-origin: 210px 210px;
  animation: pinSeat 1.6s var(--ease) 1.1s both, pinPulse 3.6s ease-in-out 2.8s infinite;
}
.pin-core {
  fill: var(--ink-deep);
  animation: pinSeat 1.6s var(--ease) 1.1s both;
}
@keyframes pinSeat {
  from { transform: scaleX(0.2); opacity: 0; }
  to { transform: none; opacity: 1; }
}
@keyframes pinPulse {
  0%, 100% { filter: drop-shadow(0 0 0 rgba(200, 160, 96, 0)); }
  50% { filter: drop-shadow(0 0 12px rgba(200, 160, 96, 0.7)); }
}
.bolts circle { animation: boltGlow 3.2s ease-in-out infinite; }
.bolts circle:nth-child(odd) { animation-delay: 1.2s; }
@keyframes boltGlow {
  0%, 100% { fill: #C8A060; }
  50% { fill: #E0D0B0; }
}
.stage-caption {
  margin-top: 14px;
  text-align: center;
  color: var(--on-dark-dim);
  font-size: 0.95rem;
  letter-spacing: 0.16em;
}

/* Pairing board */
.board-section {
  background: var(--paper);
  padding: 88px 0 80px;
}
.section-head { margin-bottom: 28px; }
.section-head h2 { margin-bottom: 12px; }

.chip-row {
  display: flex; flex-wrap: wrap; gap: 8px;
  margin-bottom: 32px;
}
.filter-chip {
  background: transparent;
  border: 1px solid var(--line);
  color: var(--muted);
  padding: 8px 16px;
  font-size: 1rem;
  letter-spacing: 0.12em;
  cursor: pointer;
  border-radius: 999px;
  transition: background .2s var(--ease), color .2s var(--ease), border-color .2s var(--ease), transform .25s var(--ease);
}
.filter-chip.is-on {
  background: var(--ink);
  color: var(--on-dark);
  border-color: var(--ink);
}

.board {
  display: grid;
  grid-template-columns: 1fr 72px 1fr;
  gap: 8px 12px;
  align-items: start;
}
.board-col { display: grid; gap: 12px; min-width: 0; }
.col-label {
  font-size: 0.9rem;
  letter-spacing: 0.22em;
  color: var(--gold-deep);
  margin-bottom: 4px;
}

.type-card,
.method-card {
  position: relative;
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 14px;
  align-items: start;
  background: var(--white);
  border: 1px solid var(--line);
  padding: 18px 18px 18px 16px;
  transition: transform .25s var(--ease), box-shadow .25s var(--ease),
    border-color .25s var(--ease), background .25s var(--ease), opacity .25s var(--ease);
}
.type-card::before,
.method-card::before,
.type-card::after,
.method-card::after {
  content: "";
  position: absolute;
  width: 6px; height: 6px;
  border: 1px solid var(--gold);
  background: var(--paper);
  border-radius: 50%;
}
.type-card::before, .method-card::before { top: 8px; left: 8px; }
.type-card::after, .method-card::after { top: 8px; right: 8px; }
.type-card.is-dim, .method-card.is-dim { opacity: 0.38; }
.type-card.is-on, .method-card.is-paired {
  border-color: var(--gold);
  box-shadow: 0 0 0 1px var(--gold);
}
.plate-no, .method-mark {
  color: var(--gold-deep);
  font-size: 1.35rem;
  letter-spacing: 0.08em;
  padding-top: 2px;
}
.type-card h3, .method-card h3 { margin-bottom: 6px; }
.type-card p, .method-card p {
  color: var(--muted);
  font-size: 0.98rem;
}

.board-rail {
  position: relative;
  min-height: 100%;
  display: flex; flex-direction: column; align-items: center;
  padding-top: 36px;
}
.rail-label {
  font-family: var(--display);
  text-transform: uppercase;
  letter-spacing: 0.28em;
  font-size: 0.8rem;
  color: var(--gold);
  writing-mode: vertical-rl;
  transform: rotate(180deg);
  margin-bottom: 12px;
}
.rail-line {
  flex: 1;
  width: 2px;
  min-height: 280px;
  background: repeating-linear-gradient(
    to bottom,
    var(--gold) 0 10px,
    transparent 10px 18px
  );
  animation: railFlow 1.6s linear infinite;
  transform-origin: top;
}
@keyframes railFlow {
  from { background-position: 0 0; }
  to { background-position: 0 18px; }
}
.rail-tick {
  position: absolute;
  left: 50%;
  width: 56px; height: 2px;
  margin-left: -28px;
  background: var(--line);
  transform: scaleX(0.4);
  transform-origin: center;
  transition: background .25s var(--ease), transform .25s var(--ease), box-shadow .25s var(--ease);
}
.rail-tick.on {
  background: var(--gold);
  transform: scaleX(1);
  box-shadow: 0 0 10px rgba(200, 160, 96, .7);
}
.rail-tick.t1 { top: 18%; }
.rail-tick.t2 { top: 38%; }
.rail-tick.t3 { top: 58%; }
.rail-tick.t4 { top: 78%; }

.match-readout {
  margin-top: 28px;
  padding: 16px 18px;
  border-left: 3px solid var(--gold);
  background: var(--paper-2);
  font-size: 1.15rem;
  letter-spacing: 0.08em;
  color: var(--ink);
}

/* Practice (dark) */
.practice {
  background: var(--ink);
  color: var(--on-dark);
  padding: 88px 0;
}
.practice-layout {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 48px;
  align-items: start;
}
.practice-lead .eyebrow { color: var(--gold-soft); }
.practice-lead h2 { margin-bottom: 18px; max-width: 16ch; }
.practice-lead p { color: var(--on-dark-dim); max-width: 54ch; }
.practice-lead p + p { margin-top: 14px; }

.practice-facts {
  display: grid;
  gap: 0;
  border-top: 1px solid rgba(200, 160, 96, 0.28);
}
.practice-facts li {
  display: grid;
  grid-template-columns: 1fr;
  gap: 4px;
  padding: 18px 0;
  border-bottom: 1px solid rgba(200, 160, 96, 0.28);
  transition: transform .25s var(--ease), background .25s var(--ease), padding-left .25s var(--ease);
}
.practice-facts strong {
  font-family: var(--display);
  font-size: 1.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--gold);
}
.practice-facts span { color: var(--on-dark-dim); }

/* Quote */
.quote-band {
  background: var(--ink-2);
  color: var(--on-dark);
  padding: 80px 0;
  text-align: center;
  border-block: 1px solid rgba(200, 160, 96, 0.22);
}
.quote-band blockquote { margin: 0; }
.quote-band p {
  font-family: var(--display);
  font-size: clamp(1.8rem, 4.4vw, 3.1rem);
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  line-height: 1.12;
  max-width: 22ch;
  margin: 0 auto;
  color: var(--on-dark);
}
.quote-band cite {
  display: block;
  margin-top: 18px;
  font-style: normal;
  color: var(--gold-soft);
  font-size: 1rem;
  letter-spacing: 0.22em;
}

/* FAQ */
.faq-section {
  background: var(--white);
  padding: 88px 0;
}
.faq-layout {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 48px;
  align-items: start;
}
.faq-intro h2 { margin-bottom: 12px; }
.faq-intro p { color: var(--muted); max-width: 36ch; }

.faq-item { border-bottom: 1px solid var(--line); }
.faq-item:first-child { border-top: 1px solid var(--line); }
.faq-q {
  width: 100%;
  background: none;
  border: 0;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 20px 0;
  text-align: left;
  color: var(--ink);
  font-size: 1.35rem;
  letter-spacing: 0.06em;
  transition: color .2s var(--ease);
}
.faq-ico {
  width: 14px; height: 14px; position: relative; flex-shrink: 0;
}
.faq-ico::before, .faq-ico::after {
  content: ""; position: absolute; background: var(--ink);
  transition: transform .25s var(--ease), opacity .25s var(--ease);
}
.faq-ico::before { width: 14px; height: 2px; top: 6px; left: 0; }
.faq-ico::after { width: 2px; height: 14px; top: 0; left: 6px; }
.faq-item.open .faq-ico::after { transform: scaleY(0); }
.faq-a { display: none; padding: 0 0 20px; }
.faq-item.open .faq-a { display: block; }
.faq-a p { color: var(--muted); max-width: 52ch; }

/* Contact */
.contact-section {
  background: var(--paper-2);
  padding: 88px 0;
}
.contact-layout {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 40px;
  align-items: start;
}
.contact-copy h2 { margin-bottom: 14px; max-width: 16ch; }
.contact-copy p { color: var(--muted); max-width: 42ch; }
.contact-email {
  display: inline-block;
  margin-top: 26px;
  font-family: var(--display);
  font-size: clamp(1.5rem, 3vw, 2.2rem);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  font-weight: 600;
  color: var(--ink);
  border-bottom: 2px solid var(--gold);
  padding-bottom: 4px;
  transition: transform .25s var(--ease), border-color .25s var(--ease);
}
.contact-addr { margin-top: 12px; color: var(--muted); font-size: 0.98rem; }

.contact-card {
  background: var(--white);
  border: 1px solid var(--line);
  padding: 32px 28px;
  display: grid;
  gap: 12px;
  transition: transform .25s var(--ease), box-shadow .25s var(--ease);
}
.contact-card h3 { margin: 0; }
.contact-card p { color: var(--muted); }
.contact-card .btn { justify-self: start; }
.contact-card .btn-ghost {
  color: var(--ink);
  border-color: var(--line-strong);
}

/* Footer (dark, near-white) */
.site-footer {
  background: var(--ink-deep);
  color: var(--on-dark);
  padding: 48px 0 28px;
  border-top: 1px solid rgba(200, 160, 96, 0.22);
}
.footer-inner {
  display: flex; justify-content: space-between; align-items: flex-start;
  gap: 28px; flex-wrap: wrap;
  padding-bottom: 28px;
  border-bottom: 1px solid rgba(200, 160, 96, 0.22);
}
.site-footer .brand { color: var(--on-dark); }
.site-footer .brand img { border-color: var(--gold-deep); }
.footer-tag { color: var(--on-dark-dim); margin-top: 12px; font-size: 0.98rem; }
.footer-nav { display: flex; gap: 22px; flex-wrap: wrap; }
.footer-nav a {
  font-family: var(--display);
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--on-dark-dim);
  font-size: 1.05rem;
}
.footer-bottom {
  display: flex; justify-content: space-between; gap: 14px; flex-wrap: wrap;
  color: var(--on-dark-dim); font-size: 14px; padding-top: 20px;
}

/* Reveal must sit before hover transforms */
.js .reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity .7s var(--ease), transform .7s var(--ease);
}
.js .reveal.in { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  .js .reveal { opacity: 1; transform: none; transition: none; }
  .hero-grid, .plate-l, .plate-r, .maze, .pin, .pin-core, .bolts circle, .rail-line {
    animation: none !important;
  }
  .maze { stroke-dashoffset: 0; }
}

/* Hover AFTER .reveal.in so lift is not overwritten */
@media (hover: hover) and (pointer: fine) {
  .btn-primary:hover {
    transform: translateY(-3px);
    background: #D4B070;
    box-shadow: 0 16px 32px -12px rgba(168, 136, 72, .7);
  }
  .btn-ghost:hover {
    transform: translateY(-3px);
    border-color: var(--gold);
    color: var(--gold-soft);
  }
  .nav a:hover { color: var(--ink); }
  .nav .nav-cta:hover {
    background: var(--ink);
    color: var(--on-dark);
  }
  .filter-chip:hover {
    transform: translateY(-2px);
    border-color: var(--gold);
    color: var(--ink);
  }
  .type-card.reveal.in:hover,
  .type-card:hover,
  .method-card.reveal.in:hover,
  .method-card:hover {
    transform: translateY(-5px);
    border-color: var(--gold);
    box-shadow: 0 18px 36px -22px rgba(48, 48, 56, .45);
  }
  .practice-facts li.reveal.in:hover,
  .practice-facts li:hover {
    transform: translateY(-3px);
    padding-left: 8px;
  }
  .faq-q:hover { color: var(--gold-deep); }
  .faq-item:hover { background: var(--paper); }
  .contact-email:hover {
    border-bottom-color: var(--ink);
    transform: translateY(-2px);
  }
  .contact-card.reveal.in:hover,
  .contact-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 22px 40px -24px rgba(48, 48, 56, .4);
  }
  .footer-nav a:hover { color: var(--on-dark); }
}

/* Tablet */
@media (max-width: 980px) {
  .nav-toggle { display: flex; }
  .nav {
    position: fixed; inset: var(--header-h) 0 auto 0;
    flex-direction: column; gap: 4px; align-items: stretch;
    background: rgba(246, 244, 238, .98);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--line);
    padding: 16px 24px 24px;
    transform: translateY(-120%);
    transition: transform .35s var(--ease);
    z-index: 90;
  }
  .nav.open { transform: translateY(0); }
  .nav a {
    padding: 12px 4px;
    font-size: 1.2rem;
    color: var(--ink);
    border-bottom: 1px solid var(--line);
  }
  .nav .nav-cta {
    text-align: center;
    margin-top: 10px;
    border: 1px solid var(--ink);
  }
  .hero-layout,
  .practice-layout,
  .faq-layout,
  .contact-layout { grid-template-columns: 1fr; }
  .board {
    grid-template-columns: 1fr;
  }
  .board-rail { display: none; }
  .hero { padding-bottom: 56px; }
  .hero-stage { width: min(100%, 340px); }
}

/* Phone ~390px */
@media (max-width: 640px) {
  .container { padding: 0 18px; }
  h1 { font-size: clamp(2.4rem, 12vw, 3.2rem); }
  .hero { padding: calc(var(--header-h) + 28px) 0 48px; min-height: auto; }
  .hero-sub { margin: 16px 0 22px; }
  .hero-actions { gap: 10px; }
  .btn { width: 100%; }
  .board-section, .practice, .faq-section, .contact-section { padding: 56px 0; }
  .quote-band { padding: 56px 0; }
  .chip-row { gap: 8px; }
  .filter-chip { font-size: 0.95rem; padding: 8px 12px; }
  .type-card, .method-card {
    grid-template-columns: 36px 1fr;
    padding: 16px 14px;
  }
  .practice-facts li { padding: 16px 0; }
  .contact-card { padding: 24px 20px; }
  .footer-inner, .footer-bottom { flex-direction: column; gap: 12px; }
  .match-readout { font-size: 1.05rem; }
}