:root {
  color-scheme: light;
  --paper: #f4f1ed;
  --paper-soft: #faf8f5;
  --ink: #181716;
  --muted: #726d68;
  --line: rgba(24, 23, 22, 0.15);
  --line-soft: rgba(24, 23, 22, 0.08);
  --red: #e23b2f;
  --red-dark: #bf2b22;
  --white: #fff;
  --serif: "Iowan Old Style", "Baskerville", "Times New Roman", "Yu Mincho", serif;
  --sans: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Hiragino Sans", "Yu Gothic", sans-serif;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  background: var(--paper);
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--sans);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; }

.shell {
  width: min(1180px, calc(100% - 48px));
  margin: 0 auto;
}

.topbar {
  min-height: 84px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  border-bottom: 1px solid var(--line);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  text-decoration: none;
  font-family: var(--serif);
  font-size: 1.48rem;
  font-weight: 700;
  letter-spacing: -0.035em;
}

.mark {
  width: 31px;
  height: 31px;
  border-radius: 8px;
  background: url("app-icon.png") center / cover no-repeat;
}

.nav {
  display: flex;
  gap: 28px;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 650;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.nav a {
  position: relative;
  text-decoration: none;
}

.nav a:hover,
.nav a:focus-visible,
.nav a[aria-current="page"] { color: var(--red); }

.hero {
  padding: clamp(78px, 12vw, 148px) 0 70px;
}

.kicker,
.eyebrow {
  color: var(--red-dark);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  text-transform: uppercase;
}

h1, h2, h3 {
  font-family: var(--serif);
  font-weight: 500;
}

.hero h1 {
  max-width: 1080px;
  margin: 20px 0 54px;
  font-size: clamp(3.35rem, 9.5vw, 8.7rem);
  line-height: 0.92;
  letter-spacing: -0.072em;
}

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

.hero-bottom {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: end;
  gap: 48px;
  padding-top: 26px;
  border-top: 1px solid var(--line);
}

.lead {
  max-width: 710px;
  margin: 0;
  color: #4e4a46;
  font-size: clamp(1.02rem, 2vw, 1.22rem);
}

.platforms {
  display: flex;
  gap: 18px;
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  white-space: nowrap;
}

.product-stage {
  padding: 0 0 clamp(88px, 11vw, 148px);
}

.ecosystem-heading {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 0.55fr);
  gap: 30px 64px;
  align-items: end;
  margin-bottom: clamp(38px, 6vw, 72px);
  padding-top: clamp(52px, 7vw, 86px);
  border-top: 1px solid var(--line);
}

.ecosystem-heading .eyebrow {
  grid-column: 1 / -1;
}

.ecosystem-heading h2 {
  margin: 0;
  font-size: clamp(2.25rem, 5.5vw, 5rem);
  line-height: 0.98;
  letter-spacing: -0.06em;
}

.platform-line { white-space: nowrap; }

.ecosystem-heading p {
  max-width: 440px;
  margin: 0;
  color: var(--muted);
}

.ecosystem-shot {
  margin: 0;
}

.ecosystem-shot img {
  display: block;
  width: 100%;
  height: auto;
  overflow: hidden;
  border: 1px solid var(--line-soft);
  border-radius: clamp(22px, 3vw, 38px);
  box-shadow: 0 34px 70px rgba(42, 33, 25, 0.14);
}

.ecosystem-shot figcaption {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  margin-top: 13px;
  color: var(--muted);
  font-size: 0.68rem;
  font-weight: 650;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.principles {
  border-top: 1px solid var(--line);
}

.principle-row {
  display: grid;
  grid-template-columns: 92px minmax(230px, 0.7fr) 1.3fr;
  gap: 40px;
  align-items: baseline;
  padding: 50px 0;
  border-bottom: 1px solid var(--line);
}

.principle-number {
  color: var(--red);
  font-family: var(--serif);
  font-size: 1.15rem;
}

.principle-row h2 {
  margin: 0;
  font-size: clamp(1.7rem, 3vw, 2.6rem);
  line-height: 1.1;
  letter-spacing: -0.04em;
}

.principle-row p {
  max-width: 600px;
  margin: 0;
  color: var(--muted);
}

.document-hero {
  padding: clamp(74px, 10vw, 130px) 0 54px;
  border-bottom: 1px solid var(--line);
}

.document-hero h1 {
  max-width: 980px;
  margin: 18px 0 24px;
  font-size: clamp(3.6rem, 9vw, 8.2rem);
  line-height: 0.92;
  letter-spacing: -0.07em;
}

.updated {
  color: var(--muted);
  font-size: 0.78rem;
}

.document-grid {
  display: grid;
  grid-template-columns: 270px minmax(0, 1fr);
  gap: clamp(48px, 9vw, 120px);
  padding: 64px 0 110px;
}

.document-aside {
  align-self: start;
  position: sticky;
  top: 28px;
  color: var(--muted);
  font-size: 0.88rem;
}

.document-aside strong {
  display: block;
  margin-bottom: 18px;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 1.65rem;
  font-weight: 500;
  line-height: 1.2;
}

.document-aside a {
  color: var(--red-dark);
  text-underline-offset: 4px;
}

.document-content section {
  padding: 0 0 38px;
}

.document-content section + section {
  padding-top: 38px;
  border-top: 1px solid var(--line);
}

.document-content h2 {
  margin: 0 0 16px;
  font-size: clamp(1.45rem, 2.6vw, 2.15rem);
  line-height: 1.2;
  letter-spacing: -0.035em;
}

.document-content p,
.document-content ul,
.document-content ol {
  max-width: 720px;
  margin-top: 0;
  color: #4e4a46;
}

.document-content li + li { margin-top: 7px; }

.document-content a {
  color: var(--red-dark);
  text-underline-offset: 4px;
}

.notice {
  padding: 20px 22px;
  border-left: 3px solid var(--red);
  background: rgba(226, 59, 47, 0.065);
}

.contact-address {
  font-family: var(--serif);
  font-size: clamp(1.25rem, 3vw, 2rem);
  letter-spacing: -0.03em;
  overflow-wrap: anywhere;
}

.english { color: var(--muted); }

.faq-item + .faq-item { margin-top: 24px; }

.footer {
  padding: 34px 0 46px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.72rem;
}

.footer-row {
  display: grid;
  grid-template-columns: 0.7fr 1fr 1.6fr;
  gap: 24px;
}

.footer a { text-underline-offset: 3px; }

@media (max-width: 900px) {
  .hero-bottom,
  .document-grid,
  .ecosystem-heading { grid-template-columns: 1fr; }

  .document-aside { position: static; }
  .ecosystem-heading .eyebrow { grid-column: auto; }
  .platforms { justify-content: flex-start; }
  .principle-row { grid-template-columns: 60px 1fr; }
  .principle-row p { grid-column: 2; }
  .footer-row { grid-template-columns: 1fr 1fr; }
  .footer-row > :last-child { grid-column: 1 / -1; }
}

@media (max-width: 650px) {
  .shell { width: min(100% - 28px, 1180px); }
  .topbar { min-height: 68px; }
  .nav { gap: 15px; font-size: 0.66rem; }
  .brand { font-size: 1.22rem; }
  .mark { width: 27px; height: 27px; }
  .hero { padding-top: 62px; }
  .hero h1 {
    margin-bottom: 38px;
    font-size: clamp(2.75rem, 12.5vw, 3.7rem);
    line-height: 0.98;
  }
  .hero-bottom { gap: 24px; }
  .platforms { flex-wrap: wrap; }
  .platform-line { white-space: normal; }
  .ecosystem-shot figcaption { font-size: 0.58rem; }
  .principle-row { grid-template-columns: 40px 1fr; gap: 18px; padding: 38px 0; }
  .document-hero h1 {
    font-size: clamp(2.65rem, 12vw, 3.6rem);
    line-height: 0.98;
  }
  .document-grid { padding-top: 48px; }
  .footer-row { grid-template-columns: 1fr; }
  .footer-row > :last-child { grid-column: auto; }
}

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