:root {
  color-scheme: dark;
  --ink: #0a0b0d;
  --surface: #12151a;
  --surface-up: #181c23;
  --line: #2b313b;
  --paper: #f2f0ea;
  --dim: #9ba8ba;
  --faint: #667185;
  --red: #d6273c;
  --green: #45b66b;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--ink);
  color: var(--paper);
  font-synthesis: none;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; min-width: 320px; background: var(--ink); }
a { color: inherit; }

.site-header,
main,
footer {
  width: min(1180px, calc(100% - 40px));
  margin-inline: auto;
}

.site-header {
  height: 82px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid rgba(242, 240, 234, .1);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-size: 20px;
  font-weight: 720;
  letter-spacing: -.03em;
}

.brand img { border-radius: 8px; }
.private-status { color: var(--dim); font-size: 13px; letter-spacing: .06em; text-transform: uppercase; }
.private-status span { display: inline-block; width: 7px; height: 7px; margin-right: 7px; border-radius: 50%; background: var(--green); }

.hero {
  min-height: 670px;
  display: grid;
  grid-template-columns: minmax(0, .86fr) minmax(480px, 1.14fr);
  align-items: center;
  gap: 56px;
  padding: 78px 0 92px;
}

.eyebrow { margin: 0 0 20px; color: #e54b5e; font-size: 12px; font-weight: 750; letter-spacing: .16em; text-transform: uppercase; }
h1 { max-width: 650px; margin: 0; font-size: clamp(56px, 6vw, 88px); line-height: .94; letter-spacing: -.065em; }
.hero-lede { max-width: 530px; margin: 28px 0; color: var(--dim); font-size: clamp(18px, 2vw, 22px); line-height: 1.55; }
.text-link { display: inline-flex; min-height: 48px; align-items: center; gap: 10px; color: var(--paper); font-weight: 700; text-decoration-thickness: 1px; text-underline-offset: 6px; }

.product-scene { position: relative; min-height: 520px; }
.chat-card,
.session-card { position: absolute; border: 1px solid var(--line); border-radius: 22px; background: linear-gradient(160deg, #181c22, #101318); box-shadow: 0 28px 80px rgba(0, 0, 0, .36); }
.chat-card { top: 46px; left: 0; width: 52%; min-height: 346px; padding: 22px; transform: rotate(-3deg); color: var(--dim); }
.chat-head { display: flex; gap: 6px; margin-bottom: 32px; }
.chat-head span { width: 7px; height: 7px; border-radius: 50%; background: #3a414d; }
.chat-label, .exercise-meta { color: #8ea0ba; font-size: 10px; font-weight: 750; letter-spacing: .14em; }
.chat-card > p:nth-of-type(2) { color: #d4d9e0; font-size: 15px; line-height: 1.55; }
.chat-lines { display: grid; gap: 9px; margin: 28px 0; }
.chat-lines i { display: block; width: 92%; height: 7px; border-radius: 8px; background: #2b3038; }
.chat-lines i:nth-child(2) { width: 74%; }
.chat-lines i:nth-child(3) { width: 86%; }
.chat-lines i:nth-child(4) { width: 60%; }
.chat-card code { display: block; padding: 12px; border: 1px solid #343b46; border-radius: 10px; color: #d7b8ff; background: #0d1014; font-size: 11px; }

.session-card { right: 0; bottom: 0; z-index: 2; width: 58%; min-height: 450px; padding: 26px; transform: rotate(2deg); }
.session-top { display: flex; justify-content: space-between; color: #9eb0c8; font-size: 10px; font-weight: 750; letter-spacing: .13em; }
.session-top small { color: #dbe1ea; }
.progress { display: grid; grid-template-columns: repeat(6, 1fr); gap: 5px; margin: 18px 0 38px; }
.progress i { height: 3px; border-radius: 4px; background: #343b46; }
.progress i:first-child { background: var(--red); }
.session-card h2 { margin: 8px 0 30px; font-size: clamp(26px, 3vw, 38px); line-height: 1; letter-spacing: -.04em; }
.set-row { min-height: 66px; display: grid; grid-template-columns: 1fr auto auto; align-items: center; gap: 24px; padding: 0 14px; border: 1px solid #353c47; border-radius: 12px; background: #1b2028; }
.set-row + .set-row { margin-top: 10px; }
.set-row span, .set-row small { display: block; color: #8ea0ba; font-size: 9px; font-weight: 700; letter-spacing: .12em; text-transform: uppercase; }
.set-row strong { font-size: 19px; }
.set-row.muted { opacity: .58; }
.log-button { margin-top: 14px; padding: 15px; border-radius: 12px; background: var(--red); text-align: center; font-size: 14px; font-weight: 750; }
.transfer-mark { position: absolute; top: 49%; left: 48%; z-index: 3; width: 48px; height: 48px; display: grid; place-items: center; border: 1px solid #414956; border-radius: 50%; background: var(--ink); color: var(--paper); font-size: 22px; }

.how { padding: 110px 0 130px; border-top: 1px solid rgba(242, 240, 234, .1); }
.how > h2 { max-width: 720px; margin: 0 0 70px; font-size: clamp(42px, 5vw, 68px); line-height: 1; letter-spacing: -.055em; }
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.steps article { min-height: 250px; padding: 26px; border: 1px solid var(--line); border-radius: 18px; background: var(--surface); }
.steps article > span { color: var(--red); font-size: 12px; font-weight: 800; letter-spacing: .12em; }
.steps h3 { margin: 72px 0 10px; font-size: 23px; letter-spacing: -.03em; }
.steps p { margin: 0; color: var(--dim); line-height: 1.6; }

.built-for { padding: 120px 0; border-top: 1px solid rgba(242, 240, 234, .1); }
.section-heading { display: grid; grid-template-columns: 1.25fr .75fr; column-gap: 50px; align-items: end; margin-bottom: 62px; }
.section-heading .eyebrow { grid-column: 1 / -1; }
.section-heading h2 { margin: 0; font-size: clamp(42px, 5vw, 68px); line-height: 1; letter-spacing: -.055em; }
.section-heading > p:last-child { max-width: 450px; margin: 0 0 6px; color: var(--dim); font-size: 17px; line-height: 1.65; }
.feature-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.feature { min-height: 390px; display: flex; flex-direction: column; padding: 30px; overflow: hidden; border: 1px solid var(--line); border-radius: 20px; background: linear-gradient(145deg, #14181e, #101318); }
.feature-wide { min-height: 350px; grid-column: 1 / -1; display: grid; grid-template-columns: .85fr 1.15fr; align-items: center; gap: 50px; }
.feature-kicker { margin: 0 0 56px; color: #e54b5e; font-size: 11px; font-weight: 750; letter-spacing: .14em; text-transform: uppercase; }
.feature h3 { max-width: 520px; margin: 0 0 14px; font-size: clamp(29px, 3vw, 42px); line-height: 1.02; letter-spacing: -.045em; }
.feature > p:last-of-type, .feature > div > p:last-child { max-width: 520px; margin: 0; color: var(--dim); line-height: 1.6; }
.metric-demo { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; padding: 18px; border: 1px solid #333a45; border-radius: 17px; background: #0b0d11; transform: rotate(-1deg); }
.metric-demo span { min-height: 94px; display: flex; flex-direction: column; justify-content: center; padding: 18px; border: 1px solid #303743; border-radius: 12px; color: var(--paper); background: #1a1f26; font-size: 26px; font-weight: 750; }
.metric-demo small { margin-bottom: 8px; color: #899ab2; font-size: 9px; letter-spacing: .14em; }
.offline-demo { min-height: 64px; display: flex; align-items: center; gap: 12px; margin-top: auto; padding: 0 18px; border: 1px solid #303743; border-radius: 13px; color: #a8b4c6; background: #0c0f13; font-size: 13px; }
.offline-demo i { width: 9px; height: 9px; border-radius: 50%; background: var(--green); box-shadow: 0 0 0 5px rgba(69, 182, 107, .1); }
.correction-demo { position: relative; min-height: 78px; display: flex; align-items: center; gap: 18px; margin-top: auto; padding: 0 18px; border: 1px solid #303743; border-radius: 13px; background: #0c0f13; font-size: 20px; font-weight: 750; }
.correction-demo span { color: var(--faint); text-decoration: line-through; }
.correction-demo::after { content: "CORRECTED"; position: absolute; top: 12px; right: 14px; color: var(--green); font-size: 8px; letter-spacing: .13em; }

.closing { padding: 145px 0 155px; border-top: 1px solid rgba(242, 240, 234, .1); text-align: center; }
.closing img { margin-bottom: 24px; border-radius: 17px; }
.closing .eyebrow { margin-bottom: 24px; }
.closing h2 { max-width: 900px; margin: 0 auto; font-size: clamp(42px, 5vw, 66px); line-height: 1.03; letter-spacing: -.055em; }
.closing > p:last-child { margin: 28px auto 0; color: var(--dim); font-size: 16px; }

footer { min-height: 116px; display: flex; align-items: center; justify-content: space-between; border-top: 1px solid rgba(242, 240, 234, .1); color: var(--dim); font-size: 13px; }
.brand-small { color: var(--paper); font-size: 17px; }

@media (max-width: 900px) {
  .hero { grid-template-columns: 1fr; padding-top: 64px; }
  .product-scene { width: min(650px, 100%); margin-inline: auto; }
}

@media (max-width: 620px) {
  .site-header, main, footer { width: min(100% - 28px, 1180px); }
  .site-header { height: 72px; }
  .private-status { font-size: 10px; }
  .hero { min-height: auto; gap: 42px; padding: 58px 0 76px; }
  h1 { font-size: clamp(48px, 15vw, 66px); }
  .hero-lede { font-size: 18px; }
  .product-scene { min-height: 580px; }
  .chat-card { width: 78%; min-height: 302px; }
  .session-card { width: 84%; min-height: 410px; padding: 21px; }
  .transfer-mark { top: 43%; left: 12%; }
  .steps { grid-template-columns: 1fr; }
  .steps article { min-height: 210px; }
  .steps h3 { margin-top: 48px; }
  .how { padding: 80px 0 90px; }
  .built-for { padding: 80px 0; }
  .section-heading { display: block; margin-bottom: 42px; }
  .section-heading h2 { margin-bottom: 24px; }
  .feature-grid, .feature-wide { grid-template-columns: 1fr; }
  .feature { min-height: 340px; padding: 24px; }
  .feature-wide { gap: 30px; }
  .feature-kicker { margin-bottom: 42px; }
  .metric-demo { padding: 12px; }
  .metric-demo span { min-height: 78px; font-size: 21px; }
  .closing { padding: 95px 0 105px; }
  footer { align-items: flex-start; flex-direction: column; justify-content: center; gap: 10px; }
  footer p { margin: 0; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}