/* ============================================================
   Relinq — landing page styles
   Dark, archival, infrastructure-grade aesthetic.
   ============================================================ */

:root {
  --bg: #07080a;
  --bg-raised: #0e1013;
  --text: #ecedef;
  --text-muted: #888e97;
  --text-faint: #565c65;
  --line: rgba(255, 255, 255, 0.075);
  --line-strong: rgba(255, 255, 255, 0.16);
  --accent: #79e6d8;
  --display: "Bricolage Grotesque", ui-sans-serif, system-ui, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, monospace;
  --maxw: 1180px;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  border-color: var(--line);
}

html {
  scroll-behavior: smooth;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--display);
  font-size: 16px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

h1, h2, h3 {
  letter-spacing: -0.025em;
  font-weight: 500;
}

a {
  color: inherit;
  text-decoration: none;
  -webkit-tap-highlight-color: transparent;
}

ul, ol {
  list-style: none;
}

::selection {
  background: rgba(121, 230, 216, 0.22);
  color: #fff;
}

:focus-visible {
  outline: 1px solid var(--accent);
  outline-offset: 3px;
}

section[id] {
  scroll-margin-top: 5rem;
}

/* ---- shared layout ---- */
.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding-left: clamp(1.5rem, 4vw, 4rem);
  padding-right: clamp(1.5rem, 4vw, 4rem);
  border-left: 1px solid var(--line);
  border-right: 1px solid var(--line);
}

.section {
  border-top: 1px solid var(--line);
  position: relative;
}

.section > .container {
  padding-top: clamp(5rem, 9vw, 8rem);
  padding-bottom: clamp(5rem, 9vw, 8rem);
}

/* ---- decorative backgrounds ---- */
.grain {
  position: fixed;
  inset: 0;
  z-index: 100;
  pointer-events: none;
  opacity: 0.022;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.82' numOctaves='3'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

.grid-backdrop {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, var(--line) 1px, transparent 1px),
    linear-gradient(to bottom, var(--line) 1px, transparent 1px);
  background-size: 68px 68px;
  -webkit-mask-image: radial-gradient(ellipse 75% 65% at 50% 28%, #000 0%, transparent 100%);
  mask-image: radial-gradient(ellipse 75% 65% at 50% 28%, #000 0%, transparent 100%);
}

.hero-glow {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(58% 40% at 50% 4%, rgba(121, 230, 216, 0.11), transparent 72%),
    radial-gradient(36% 30% at 84% 38%, rgba(121, 230, 216, 0.06), transparent 70%);
}

.cta-glow {
  position: absolute;
  inset: 0;
  background: radial-gradient(50% 70% at 50% 50%, rgba(121, 230, 216, 0.1), transparent 72%);
}

/* ============================================================
   HEADER
   ============================================================ */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 50;
  background: rgba(7, 8, 10, 0.72);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
  transition: border-color 0.3s ease;
}

.site-header.scrolled {
  border-bottom-color: var(--line-strong);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.brand-mark {
  height: 30px;
  width: auto;
  display: block;
}

.brand-name {
  font-size: 15px;
  font-weight: 500;
  letter-spacing: -0.02em;
}

.brand-tag {
  font-family: var(--mono);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.22em;
  color: var(--text-faint);
}

.site-nav {
  display: flex;
  gap: 2.25rem;
}

.site-nav a {
  font-family: var(--mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--text-muted);
  transition: color 0.25s ease;
}

.site-nav a:hover {
  color: var(--text);
}

.header-cta {
  font-family: var(--mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  padding: 0.55rem 1.25rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  transition: border-color 0.3s ease, color 0.3s ease;
}

.header-cta:hover {
  border-color: rgba(121, 230, 216, 0.5);
  color: var(--accent);
}

/* ============================================================
   BUTTONS
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.65rem;
  padding: 0.95rem 1.75rem;
  border-radius: 999px;
  font-family: var(--mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  border: 1px solid transparent;
  transition: all 0.3s ease;
}

.btn .ic-arrow {
  width: 14px;
  height: 14px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  transition: transform 0.3s ease;
}

.btn-primary {
  border-color: rgba(121, 230, 216, 0.3);
  background: rgba(121, 230, 216, 0.06);
  color: var(--accent);
}

.btn-primary:hover {
  border-color: rgba(121, 230, 216, 0.6);
  background: rgba(121, 230, 216, 0.1);
  box-shadow: 0 0 46px -10px rgba(121, 230, 216, 0.55);
}

.btn-primary:hover .ic-arrow {
  transform: translateX(4px);
}

.btn-ghost {
  border-color: var(--line);
  color: var(--text-muted);
}

.btn-ghost:hover {
  border-color: var(--line-strong);
  color: var(--text);
}

.btn-ghost:hover .ic-down {
  transform: translateY(3px);
}

/* ============================================================
   HERO
   ============================================================ */
.hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: -1;
}

.hero-bg .grid-backdrop {
  opacity: 0.6;
}

.hero-inner {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding-top: 8rem;
  padding-bottom: 5rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  align-items: center;
  gap: 2.5rem;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  padding: 0.4rem 0.95rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-family: var(--mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--text-muted);
}

.badge-dot {
  position: relative;
  display: inline-flex;
  width: 6px;
  height: 6px;
}

.badge-dot .ping {
  position: absolute;
  inset: 0;
  border-radius: 999px;
  background: var(--accent);
  opacity: 0.6;
  animation: ping 2s cubic-bezier(0, 0, 0.2, 1) infinite;
}

.badge-dot .dot {
  position: relative;
  width: 6px;
  height: 6px;
  border-radius: 999px;
  background: var(--accent);
}

@keyframes ping {
  75%, 100% { transform: scale(2.4); opacity: 0; }
}

.hero-title {
  margin-top: 1.75rem;
  font-size: clamp(2.6rem, 6.4vw, 4.6rem);
  line-height: 1.02;
  font-weight: 500;
  text-wrap: balance;
}

.hero-sub {
  margin-top: 1.5rem;
  max-width: 36rem;
  font-size: clamp(0.95rem, 1.3vw, 1.05rem);
  line-height: 1.65;
  color: var(--text-muted);
  text-wrap: pretty;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 2.25rem;
}

.spec-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.5rem;
  margin-top: 2.5rem;
  font-family: var(--mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--text-faint);
}

.spec-strip li {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.spec-dot {
  width: 4px;
  height: 4px;
  border-radius: 999px;
  background: rgba(121, 230, 216, 0.7);
}

.hero-visual {
  display: flex;
  justify-content: flex-end;
}

/* ---- QR diagram ---- */
.qr-diagram {
  width: 100%;
  max-width: 540px;
  height: auto;
}

.dg-eyebrow {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 2px;
  fill: var(--text-faint);
}

.dg-caption {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 2.5px;
  fill: var(--text-muted);
}

.qr-card {
  fill: var(--bg-raised);
  stroke: var(--line-strong);
}

#qr-modules rect {
  fill: rgba(236, 237, 239, 0.92);
}

.conn {
  fill: none;
  stroke: var(--line-strong);
  stroke-width: 1;
  transition: stroke 0.6s ease, stroke-width 0.6s ease;
}

.conn.active {
  stroke: var(--accent);
  stroke-width: 1.6;
  filter: url(#glow);
}

.origin-dot {
  fill: var(--accent);
  filter: url(#glow);
}

.chip-box {
  fill: var(--bg-raised);
  stroke: var(--line);
  transition: fill 0.6s ease, stroke 0.6s ease;
}

.chip.active .chip-box {
  fill: rgba(121, 230, 216, 0.06);
  stroke: var(--accent);
}

.chip-dot {
  fill: var(--text-faint);
  transition: fill 0.6s ease;
}

.chip.active .chip-dot {
  fill: var(--accent);
  filter: url(#glow);
}

.chip-label {
  font-family: var(--mono);
  font-size: 12.5px;
  fill: var(--text-muted);
  transition: fill 0.6s ease;
}

.chip.active .chip-label {
  fill: var(--accent);
}

.chip-live {
  font-family: var(--mono);
  font-size: 9px;
  letter-spacing: 1.5px;
  fill: var(--accent);
  opacity: 0;
  transition: opacity 0.6s ease;
}

.chip.active .chip-live {
  opacity: 1;
}

/* ============================================================
   SECTION PRIMITIVES
   ============================================================ */
.label {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-family: var(--mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.24em;
  color: var(--text-faint);
}

.label-index {
  color: rgba(121, 230, 216, 0.8);
}

.label-tick {
  width: 2.5rem;
  height: 1px;
  background: var(--line-strong);
}

.section-title {
  margin-top: 3rem;
  max-width: 18ch;
  font-size: clamp(1.9rem, 3.6vw, 2.9rem);
  line-height: 1.1;
  text-wrap: balance;
}

.section-title.wide {
  max-width: 24ch;
}

.split {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 4rem;
}

.split .section-title {
  margin-top: 3rem;
}

.prose {
  margin-top: 3rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--text-muted);
}

.prose-strong {
  color: var(--text);
}

/* ---- problem status line ---- */
.status-line {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  margin-top: 3.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--line);
  font-family: var(--mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--text-muted);
}

.status-comment, .status-faint {
  color: var(--text-faint);
}

.status-chip {
  padding: 0.25rem 0.55rem;
  border: 1px solid var(--line);
  border-radius: 3px;
  color: var(--text-faint);
}

/* ============================================================
   SOLUTION — steps
   ============================================================ */
.step-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  margin-top: 4rem;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
}

.step {
  background: var(--bg);
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.step-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.step-n {
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--accent);
}

.step-tag {
  font-family: var(--mono);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--text-faint);
}

.step h3 {
  font-size: 1.125rem;
  line-height: 1.35;
}

.step p {
  font-size: 0.9rem;
  line-height: 1.65;
  color: var(--text-muted);
}

/* ============================================================
   FEATURE + USE CASE GRIDS
   ============================================================ */
.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  margin-top: 4rem;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
}

.feature-card {
  background: var(--bg);
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  transition: background 0.3s ease;
}

.feature-card:hover {
  background: var(--bg-raised);
}

.feature-card .ic {
  width: 20px;
  height: 20px;
  fill: none;
  stroke: var(--accent);
  stroke-width: 1.6;
  stroke-linecap: round;
  stroke-linejoin: round;
  transition: transform 0.3s ease;
}

.feature-card:hover .ic {
  transform: translateY(-2px);
}

.feature-card h3 {
  font-size: 0.95rem;
}

.feature-card p {
  font-size: 0.875rem;
  line-height: 1.65;
  color: var(--text-muted);
}

.case-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  margin-top: 4rem;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
}

.case-card {
  background: var(--bg);
  padding: 1.75rem;
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  transition: background 0.3s ease;
}

.case-card:hover {
  background: var(--bg-raised);
}

.case-card h3 {
  font-size: 0.95rem;
}

.case-card p {
  margin-top: 0.4rem;
  font-size: 0.875rem;
  color: var(--text-muted);
}

.case-index {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--text-faint);
  transition: color 0.3s ease;
}

.case-card:hover .case-index {
  color: var(--accent);
}

/* ============================================================
   TRUST
   ============================================================ */
.trust-list {
  margin-top: 3rem;
  display: flex;
  flex-direction: column;
}

.trust-item {
  display: flex;
  gap: 1.25rem;
  padding: 1.5rem 0;
  border-top: 1px solid var(--line);
}

.trust-item:first-child {
  border-top: none;
  padding-top: 0;
}

.trust-mark {
  flex-shrink: 0;
  margin-top: 0.35rem;
  width: 18px;
  height: 18px;
  display: grid;
  place-items: center;
  border: 1px solid rgba(121, 230, 216, 0.35);
  border-radius: 4px;
}

.trust-mark::before {
  content: "";
  width: 5px;
  height: 5px;
  border-radius: 999px;
  background: var(--accent);
}

.trust-item h3 {
  font-size: 0.95rem;
}

.trust-item p {
  margin-top: 0.35rem;
  font-size: 0.875rem;
  line-height: 1.65;
  color: var(--text-muted);
}

/* ============================================================
   FINAL CTA
   ============================================================ */
.final-cta {
  position: relative;
  isolation: isolate;
  overflow: hidden;
}

.final-bg {
  position: absolute;
  inset: 0;
  z-index: -1;
}

.final-bg .grid-backdrop {
  opacity: 0.5;
}

.final-inner {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.final-title {
  font-size: clamp(2.2rem, 5vw, 3.6rem);
  line-height: 1.05;
}

.final-sub {
  margin-top: 1.25rem;
  max-width: 34rem;
  font-size: 0.95rem;
  line-height: 1.65;
  color: var(--text-muted);
}

.final-inner .btn {
  margin-top: 2.25rem;
}

/* ============================================================
   FOOTER
   ============================================================ */
.site-footer {
  border-top: 1px solid var(--line);
}

.footer-top {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 3rem;
  padding-top: 4rem;
  padding-bottom: 4rem;
}

.footer-lockup {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.footer-mark {
  height: 28px;
  width: auto;
  display: block;
}

.footer-brand p {
  margin-top: 0.85rem;
  max-width: 16rem;
  font-size: 0.875rem;
  color: var(--text-muted);
}

.footer-col {
  display: flex;
  flex-direction: column;
  gap: 0.7rem;
}

.footer-heading {
  font-family: var(--mono);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.22em;
  color: var(--text-faint);
  margin-bottom: 0.4rem;
}

.footer-col a {
  font-size: 0.875rem;
  color: var(--text-muted);
  transition: color 0.25s ease;
}

.footer-col a:hover {
  color: var(--text);
}

.footer-meta {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 1.5rem;
  padding-bottom: 1.5rem;
  border-top: 1px solid var(--line);
  font-family: var(--mono);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--text-faint);
}

.footer-wordmark {
  border-top: 1px solid var(--line);
  overflow: hidden;
}

.footer-wordmark span {
  display: block;
  padding: 1.5rem 0;
  text-align: center;
  font-size: 18vw;
  font-weight: 600;
  line-height: 1;
  letter-spacing: -0.04em;
  color: rgba(255, 255, 255, 0.025);
  user-select: none;
}

/* ============================================================
   COMING SOON MODAL
   ============================================================ */
.modal[hidden] {
  display: none;
}

.modal {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: grid;
  place-items: center;
  padding: 1.5rem;
}

.modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(4, 5, 6, 0.78);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  animation: modal-fade 0.25s ease;
}

.modal-card {
  position: relative;
  width: 100%;
  max-width: 30rem;
  padding: 2.5rem 2.25rem 2.25rem;
  text-align: center;
  background: var(--bg-raised);
  border: 1px solid var(--line-strong);
  border-radius: 16px;
  box-shadow: 0 30px 80px -24px rgba(0, 0, 0, 0.85),
    0 0 70px -28px rgba(121, 230, 216, 0.35);
  animation: modal-pop 0.3s cubic-bezier(0.22, 1, 0.36, 1);
}

@keyframes modal-fade {
  from { opacity: 0; }
}

@keyframes modal-pop {
  from { opacity: 0; transform: translateY(12px) scale(0.98); }
}

.modal-x {
  position: absolute;
  top: 0.9rem;
  right: 0.9rem;
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  transition: border-color 0.25s ease, color 0.25s ease;
}

.modal-x:hover {
  border-color: var(--line-strong);
  color: var(--text);
}

.modal-x svg {
  width: 15px;
  height: 15px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
}

.modal-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-family: var(--mono);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--accent);
}

.modal-title {
  margin-top: 1.1rem;
  font-size: 1.85rem;
}

.modal-desc {
  margin: 0.9rem auto 0;
  max-width: 24rem;
  font-size: 0.9rem;
  line-height: 1.65;
  color: var(--text-muted);
}

.modal-action {
  margin-top: 1.9rem;
  padding: 0.85rem 2rem;
  font-family: var(--mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--accent);
  background: rgba(121, 230, 216, 0.06);
  border: 1px solid rgba(121, 230, 216, 0.3);
  border-radius: 999px;
  cursor: pointer;
  transition: all 0.3s ease;
}

.modal-action:hover {
  border-color: rgba(121, 230, 216, 0.6);
  background: rgba(121, 230, 216, 0.1);
  box-shadow: 0 0 40px -12px rgba(121, 230, 216, 0.55);
}

/* ============================================================
   ENTRANCE ANIMATION
   ============================================================ */
.reveal {
  opacity: 0;
  transform: translateY(16px);
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
  transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1),
    transform 0.7s cubic-bezier(0.22, 1, 0.36, 1);
  transition-delay: var(--d, 0s);
}

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 940px) {
  .hero-inner {
    min-height: auto;
    justify-content: flex-start;
    padding-top: 8.5rem;
    padding-bottom: 4.5rem;
  }
  .hero-grid { grid-template-columns: 1fr; gap: 3.5rem; }
  .hero-visual { justify-content: center; }
  .hero-visual .qr-diagram { max-width: 460px; }
  .split { grid-template-columns: 1fr; gap: 1.5rem; }
  .split .section-title { margin-bottom: 0; }
  .prose { margin-top: 0; }
  .step-grid { grid-template-columns: 1fr; }
  .card-grid { grid-template-columns: repeat(2, 1fr); }
  .case-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-top { grid-template-columns: 1fr 1fr; gap: 2.5rem; }
}

@media (max-width: 720px) {
  .site-nav { display: none; }
  .brand-tag { display: none; }
}

@media (max-width: 560px) {
  .card-grid { grid-template-columns: 1fr; }
  .case-grid { grid-template-columns: 1fr; }
  .footer-top { grid-template-columns: 1fr; gap: 2rem; }
  .footer-meta { flex-direction: column; }
  .hero-inner { padding-top: 7rem; }
  .btn { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .badge-dot .ping { animation: none; }
  .modal-backdrop, .modal-card { animation: none; }
  * { transition-duration: 0.01ms !important; }
}