@import url("https://fonts.googleapis.com/css2?family=IBM+Plex+Mono:wght@400;500&family=Inter:wght@400;450;600;650&display=swap");

:root {
  --ink: #0a1013;
  --paper: #f2f3f0;
  --paper-2: #e9ece8;
  --navy: #071015;
  --cyan: #38e2d2;
  --line: rgba(9, 20, 24, 0.16);
  --font-sans: "Inter", system-ui, sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, monospace;
}

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

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: #020608;
  color: #fff;
  font-family: var(--font-sans);
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
h1, h2, h3, p { margin: 0; }

.site-shell {
  max-width: 1800px;
  margin: 0 auto;
  overflow: hidden;
  background: var(--navy);
}

/* Header */
.site-header {
  position: fixed;
  z-index: 40;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: min(1800px, 100%);
  height: 78px;
  padding: 0 clamp(24px, 5vw, 86px);
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  background: linear-gradient(180deg, rgba(3, 10, 14, 0.94), rgba(3, 10, 14, 0.48), transparent);
  backdrop-filter: blur(12px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 16px;
  font-weight: 650;
  letter-spacing: 0.3em;
}

.brand-logo {
  display: block;
  height: 34px;
  width: auto;
}

.brand-logo--footer {
  height: 28px;
}

.site-header nav {
  display: flex;
  gap: 34px;
  font-size: 14px;
  color: #cad2d4;
}

.site-header nav a { transition: color 0.2s; }
.site-header nav a:hover { color: var(--cyan); }
.site-header > .button { justify-self: end; }

/* Logo mark */
.relayn-mark {
  position: relative;
  display: inline-block;
  width: 66px;
  height: 66px;
}

.relayn-mark i {
  position: absolute;
  left: 50%;
  top: 50%;
  border: 1px solid var(--cyan);
  border-radius: 50%;
  transform: translate(-50%, -50%);
}

.relayn-mark i:nth-child(1) {
  width: 18px;
  height: 18px;
  background: var(--cyan);
  box-shadow: 0 0 20px rgba(56, 226, 210, 0.55);
}

.relayn-mark i:nth-child(2) {
  width: 38px;
  height: 38px;
  border-style: dashed;
}

.relayn-mark i:nth-child(3) {
  width: 62px;
  height: 62px;
  opacity: 0.45;
}

.relayn-mark--small { width: 22px; height: 22px; }
.relayn-mark--small i:nth-child(1) { width: 6px; height: 6px; }
.relayn-mark--small i:nth-child(2) { width: 13px; height: 13px; }
.relayn-mark--small i:nth-child(3) { width: 21px; height: 21px; }

/* Buttons */
.button {
  height: 50px;
  padding: 0 23px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  border: 1px solid rgba(255, 255, 255, 0.55);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.03em;
  transition: transform 0.2s;
}

.button:hover { transform: translateY(-1px); }
.button--small { height: 40px; padding: 0 18px; }
.button--primary { color: #03110f; background: var(--cyan); border-color: var(--cyan); }
.button--ghost, .button--outline { background: rgba(5, 14, 18, 0.15); }

/* Hero */
.hero {
  position: relative;
  min-height: 780px;
  padding: 160px clamp(24px, 6vw, 110px) 80px;
  display: flex;
  align-items: center;
  background: url("/relayn-hero.png") center / cover no-repeat;
}

.hero-shade {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(2, 8, 12, 0.97) 0%, rgba(2, 8, 12, 0.85) 27%, rgba(2, 8, 12, 0.28) 53%, rgba(2, 8, 12, 0.05) 100%),
    linear-gradient(180deg, rgba(2, 8, 12, 0.35), transparent 58%, rgba(2, 8, 12, 0.52));
}

.hero-content {
  position: relative;
  z-index: 2;
  width: min(760px, 55vw);
}

.eyebrow, .section-index {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  color: var(--cyan);
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 30px;
}

.eyebrow span {
  display: block;
  width: 28px;
  height: 1px;
  background: var(--cyan);
}

.hero h1 {
  font-size: clamp(56px, 6.25vw, 108px);
  line-height: 0.94;
  font-weight: 450;
  letter-spacing: -0.064em;
}

.accent { color: var(--cyan); }

.hero-lede {
  max-width: 630px;
  margin-top: 30px;
  font-size: 16px;
  line-height: 1.65;
  color: #c1cbcd;
}

.hero-actions {
  display: flex;
  gap: 12px;
  margin-top: 34px;
}

.hero-caption {
  position: absolute;
  z-index: 2;
  left: clamp(24px, 6vw, 110px);
  right: clamp(24px, 6vw, 110px);
  bottom: 30px;
  display: flex;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.18em;
  color: #8c999d;
}

/* Feature strip */
.feature-strip {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  background: var(--paper);
  color: var(--ink);
  padding: 0 clamp(20px, 5vw, 90px);
  border-bottom: 1px solid var(--line);
}

.feature-strip > div {
  min-height: 112px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 22px;
  border-right: 1px solid var(--line);
}

.feature-strip > div:last-child { border-right: 0; }
.feature-icon { font-size: 25px; color: #167f78; }
.feature-strip p { font-size: 11px; line-height: 1.5; letter-spacing: 0.03em; }
.feature-strip b { font-weight: 650; }

/* Light sections */
.section-light { background: var(--paper); color: var(--ink); }

.certainty, .os-section {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: 7vw;
  padding: 110px clamp(24px, 7vw, 125px);
  border-bottom: 1px solid var(--line);
}

.section-copy {
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.section-index { color: #168c84; margin-bottom: 28px; }

.section-copy h2,
.applications h2,
.vision h2 {
  font-size: clamp(42px, 4.4vw, 76px);
  line-height: 1.02;
  font-weight: 450;
  letter-spacing: -0.055em;
}

.section-copy h2 span { color: #8b9698; }

.section-copy > p:last-child {
  max-width: 540px;
  margin-top: 30px;
  color: #657075;
  font-size: 15px;
  line-height: 1.65;
}

/* Decision visual */
.decision-visual {
  min-height: 360px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(10px, 2.5vw, 32px);
  padding: 12px 0 8px;
}

.decision-cluster {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
}

.decision-label {
  color: #687477;
  font: 10px var(--font-mono);
  letter-spacing: 0.08em;
  text-align: center;
  max-width: 190px;
  line-height: 1.4;
}

.decision-connector {
  position: relative;
  flex: 0 0 clamp(56px, 10vw, 110px);
  width: clamp(56px, 10vw, 110px);
  height: 1px;
  align-self: center;
  margin-top: -42px;
}

.signal-cloud {
  position: relative;
  width: 215px;
  height: 210px;
}

.signal-cloud i {
  position: absolute;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: #889496;
  box-shadow: 0 0 0 8px rgba(91, 103, 106, 0.07);
}

.signal-cloud i:nth-child(1) { left: 20%; top: 20%; }
.signal-cloud i:nth-child(2) { left: 65%; top: 12%; }
.signal-cloud i:nth-child(3) { left: 44%; top: 48%; }
.signal-cloud i:nth-child(4) { left: 8%; top: 70%; }
.signal-cloud i:nth-child(5) { left: 78%; top: 76%; }

.signal-cloud::before,
.signal-cloud::after {
  content: "";
  position: absolute;
  inset: 30px;
  border: 1px solid #aab3b4;
  border-radius: 45% 55% 50% 50%;
  transform: rotate(18deg);
}

.signal-cloud::after {
  inset: 55px 20px 45px 40px;
  transform: rotate(-24deg);
}

.signal-line {
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 1px;
  background: linear-gradient(90deg, #a5aeaf, var(--cyan));
  z-index: 2;
}

.gate {
  position: absolute;
  left: 48%;
  top: 50%;
  transform: translate(-50%, -50%);
  background: var(--paper);
  border: 1px solid #168c84;
  color: #168c84;
  padding: 8px 10px;
  font: 9px var(--font-mono);
  letter-spacing: 0.14em;
}

.deterministic-rings {
  position: relative;
  width: 240px;
  height: 240px;
}

.deterministic-rings i {
  position: absolute;
  left: 50%;
  top: 50%;
  border: 1px solid #27a89f;
  border-radius: 50%;
  transform: translate(-50%, -50%);
}

.deterministic-rings i:nth-child(1) { width: 55px; height: 55px; }
.deterministic-rings i:nth-child(2) { width: 105px; height: 105px; }
.deterministic-rings i:nth-child(3) { width: 155px; height: 155px; }
.deterministic-rings i:nth-child(4) { width: 215px; height: 215px; opacity: 0.45; }

.deterministic-rings b {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background: var(--ink);
  transform: translate(-50%, -50%);
  box-shadow: 0 0 0 8px rgba(56, 226, 210, 0.18);
}

/* OS diagram */
.os-section { background: var(--paper-2); }

.os-diagram {
  min-height: 400px;
  display: grid;
  grid-template-columns: 1fr 90px 190px 90px 1fr;
  align-items: center;
}

.source-list, .output-list {
  display: flex;
  flex-direction: column;
  gap: 13px;
  color: #536065;
  font-size: 11px;
}

.source-list span, .output-list span {
  display: flex;
  align-items: center;
  gap: 10px;
}

.source-list i, .output-list i {
  width: 34px;
  height: 34px;
  border: 1px solid #c3ccca;
  border-radius: 5px;
  display: grid;
  place-items: center;
  font-style: normal;
  color: #168c84;
}

.flow-arrow {
  height: 1px;
  background: #8dbcb8;
  position: relative;
}

.flow-arrow i {
  position: absolute;
  right: 0;
  width: 7px;
  height: 7px;
  border-top: 1px solid #168c84;
  border-right: 1px solid #168c84;
  transform: rotate(45deg) translateY(-4px);
}

.flow-arrow i:nth-child(2) { right: 18px; }
.flow-arrow i:nth-child(3) { right: 36px; }

.os-core {
  width: 180px;
  height: 210px;
  margin: auto;
  border-radius: 12px;
  background: linear-gradient(145deg, #0f1c21, #071015);
  color: #fff;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  box-shadow: 0 22px 42px rgba(23, 43, 48, 0.22);
}

.os-core small {
  font: 10px var(--font-mono);
  letter-spacing: 0.2em;
  margin-top: 8px;
}

.os-core em {
  font: 7px var(--font-mono);
  font-style: normal;
  letter-spacing: 0.11em;
  color: #6f8286;
  margin-top: 18px;
}

.output-list { padding-left: 12px; }

/* Metrics */
.metrics {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  padding: 0 clamp(20px, 5vw, 90px);
  background: linear-gradient(180deg, #0b161b, #071015);
}

.metrics > div {
  min-height: 190px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border-right: 1px solid rgba(255, 255, 255, 0.13);
}

.metrics > div:last-child { border-right: 0; }
.metrics strong {
  font-size: clamp(28px, 3vw, 48px);
  font-weight: 450;
  letter-spacing: -0.04em;
}

.metrics span {
  margin-top: 12px;
  text-align: center;
  color: #9eabad;
  font-size: 11px;
  line-height: 1.5;
}

/* Partners */
.supported {
  position: relative;
  padding: 82px clamp(24px, 7vw, 120px) 92px;
  background: #050a0d;
  background-image:
    linear-gradient(rgba(91, 121, 128, 0.08) 1px, transparent 1px),
    linear-gradient(90deg, rgba(91, 121, 128, 0.08) 1px, transparent 1px);
  background-size: 76px 76px;
}

.supported-kicker {
  text-align: center;
  color: #66757c;
  font: 10px var(--font-mono);
  letter-spacing: 0.32em;
  margin-bottom: 65px;
}

.supported-row {
  max-width: 1120px;
  margin: auto;
  display: grid;
  grid-template-columns: 1fr 1px 1fr;
  align-items: center;
  gap: 70px;
}

.partner-divider {
  height: 105px;
  background: rgba(255, 255, 255, 0.15);
}

.partner-logo {
  min-height: 110px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.elevenlabs-logo { gap: 18px; }
.elevenlabs-bars { display: flex; gap: 5px; }
.elevenlabs-bars i { width: 6px; height: 55px; background: #fff; }
.elevenlabs-name {
  font-size: clamp(32px, 3.5vw, 56px);
  font-weight: 650;
  letter-spacing: -0.055em;
}

.partner-program {
  font-size: clamp(28px, 3vw, 48px);
  font-weight: 400;
  color: #c6ced0;
  letter-spacing: -0.055em;
}

.nvidia-logo { gap: 24px; color: #76b900; }
.nvidia-eye { width: 110px; height: 76px; }
.nvidia-copy { display: flex; flex-direction: column; color: #fff; }
.nvidia-copy b {
  font-size: clamp(34px, 4vw, 60px);
  line-height: 0.9;
  letter-spacing: -0.05em;
}

.nvidia-copy small {
  margin-top: 10px;
  color: #8d9b9e;
  font-size: clamp(16px, 1.8vw, 25px);
}

/* Applications */
.applications {
  padding: 105px clamp(24px, 6vw, 110px) 115px;
}

.applications-heading {
  display: grid;
  grid-template-columns: 1fr 0.55fr;
  align-items: end;
  gap: 60px;
  margin: 26px 0 58px;
}

.applications-heading p {
  max-width: 500px;
  color: #667175;
  line-height: 1.65;
  font-size: 14px;
  padding-bottom: 8px;
}

.application-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  align-items: stretch;
}

.application-grid article {
  background: #fff;
  border: 1px solid #dce1de;
  display: flex;
  flex-direction: column;
  height: 100%;
}

.application-image {
  position: relative;
  height: 490px;
  overflow: hidden;
  background-size: cover;
  background-position: center;
  flex-shrink: 0;
}

.application-image span {
  position: absolute;
  top: 14px;
  left: 14px;
  color: rgba(255, 255, 255, 0.8);
  font: 9px var(--font-mono);
  letter-spacing: 0.15em;
}

.application-image::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 45%, rgba(3, 8, 10, 0.62));
}

.application-image.energy {
  background-image: linear-gradient(145deg, rgba(12, 30, 35, 0.05), rgba(5, 10, 12, 0.45)), url("/application-energy.png");
}

.application-image.transport {
  background-image: linear-gradient(145deg, rgba(12, 30, 35, 0.05), rgba(5, 10, 12, 0.44)), url("/application-transport.png");
}

.application-image.biotech {
  background-image: linear-gradient(145deg, rgba(12, 30, 35, 0.08), rgba(5, 10, 12, 0.42)), url("/application-biotech.png");
}

.application-image.defense {
  background-image: linear-gradient(145deg, rgba(12, 30, 35, 0.08), rgba(5, 10, 12, 0.45)), url("/application-defense.png");
}

.application-copy {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 18px 20px 22px;
}

.application-grid h3 {
  font-size: 15px;
  font-weight: 600;
  line-height: 1.35;
  min-height: 2.7em;
  margin: 0;
}

.application-grid p {
  color: #697478;
  font-size: 14px;
  line-height: 1.55;
  margin: 8px 0 0;
}

/* Vision */
.vision {
  position: relative;
  padding: 110px clamp(24px, 7vw, 125px);
  background: #050a0d url("/vision-background.png") center / cover no-repeat;
}

.vision-shade {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(2, 8, 12, 0.94) 0%, rgba(2, 8, 12, 0.82) 42%, rgba(2, 8, 12, 0.45) 100%),
    linear-gradient(180deg, rgba(2, 8, 12, 0.35), transparent 55%, rgba(2, 8, 12, 0.55));
}

.vision-inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr 0.65fr;
  gap: 8vw;
  align-items: end;
}

.vision .section-index { color: var(--cyan); margin-bottom: 28px; }
.vision-copy p { color: #a7b3b6; font-size: 16px; line-height: 1.7; margin-bottom: 32px; }

/* Footer */
footer {
  min-height: 100px;
  padding: 25px clamp(24px, 5vw, 90px);
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 30px;
  background: #020507;
  color: #637075;
  font-size: 10px;
}

footer > span:last-child { text-align: right; }

/* Responsive */
@media (max-width: 1050px) {
  .site-header { grid-template-columns: 1fr auto; }
  .site-header nav { display: none; }
  .hero-content { width: min(760px, 75vw); }
  .certainty, .os-section { grid-template-columns: 1fr; }
  .application-grid { grid-template-columns: repeat(2, 1fr); }
  .application-grid h3 { min-height: 2.7em; }
  .os-diagram { max-width: 760px; }
  .supported-row { gap: 30px; }
  .partner-program { display: none; }
}

@media (max-width: 720px) {
  .site-header { height: 68px; }
  .site-header > .button { display: none; }
  .hero { min-height: 710px; padding-top: 120px; background-position: 58% center; }
  .hero-content { width: 100%; }
  .hero h1 { font-size: clamp(46px, 13vw, 66px); }
  .hero-lede { font-size: 14px; }
  .hero-actions { align-items: flex-start; flex-direction: column; }
  .hero-caption { display: none; }
  .feature-strip, .metrics { grid-template-columns: repeat(2, 1fr); padding: 0; }
  .feature-strip > div, .metrics > div { min-height: 105px; border-bottom: 1px solid var(--line); }
  .certainty, .os-section { padding: 75px 24px; }
  .section-copy h2, .applications h2, .vision h2 { font-size: 44px; }
  .decision-visual { min-height: 300px; transform: scale(0.88); margin-inline: -20px; gap: 8px; }
  .decision-connector { margin-top: -36px; flex-basis: 40px; width: 40px; }
  .decision-label { font-size: 9px; max-width: 130px; }
  .os-diagram { grid-template-columns: 1fr; gap: 18px; }
  .flow-arrow { width: 1px; height: 40px; margin: auto; }
  .flow-arrow i { display: none; }
  .source-list, .output-list { display: grid; grid-template-columns: repeat(2, 1fr); }
  .output-list { padding: 0; }
  .os-core { order: -1; }
  .supported { padding: 65px 24px; }
  .supported-kicker { margin-bottom: 36px; }
  .supported-row { grid-template-columns: 1fr; gap: 22px; }
  .partner-divider { width: 100%; height: 1px; }
  .partner-logo { min-height: 90px; }
  .elevenlabs-name, .nvidia-copy b { font-size: 38px; }
  .elevenlabs-bars i { height: 42px; }
  .nvidia-eye { width: 86px; }
  .applications { padding: 78px 24px; }
  .applications-heading { grid-template-columns: 1fr; gap: 20px; }
  .application-grid { grid-template-columns: 1fr; }
  .application-image { height: 320px; }
  .application-grid h3 { font-size: 15px; min-height: 0; }
  .application-grid p { font-size: 14px; }
  .vision { padding: 80px 24px; }
  .vision-inner { grid-template-columns: 1fr; }
  footer { grid-template-columns: 1fr; text-align: center; }
  footer .brand { justify-content: center; }
  footer > span:last-child { text-align: center; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .button { transition: none; }
}