:root {
  color-scheme: light dark;
  --background: #f4f7ff;
  --surface: rgba(255, 255, 255, 0.82);
  --surface-strong: #ffffff;
  --text: #10162a;
  --muted: #5a647c;
  --line: rgba(27, 53, 112, 0.14);
  --blue: #145bd7;
  --indigo: #3637df;
  --blue-soft: #e5edff;
  --shadow: 0 24px 70px rgba(31, 61, 129, 0.13);
  --radius: 24px;
  --page: 1120px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --background: #090d1b;
    --surface: rgba(19, 25, 45, 0.82);
    --surface-strong: #13192d;
    --text: #f4f6ff;
    --muted: #aab4ce;
    --line: rgba(180, 197, 255, 0.15);
    --blue: #70a5ff;
    --indigo: #8a8cff;
    --blue-soft: #17264d;
    --shadow: 0 24px 70px rgba(0, 0, 0, 0.32);
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at 5% -10%, rgba(18, 124, 231, 0.22), transparent 36rem),
    radial-gradient(circle at 100% 0%, rgba(56, 55, 223, 0.18), transparent 32rem),
    var(--background);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", Arial, sans-serif;
  line-height: 1.65;
}

a { color: var(--blue); text-underline-offset: 0.18em; }
a:hover { text-decoration-thickness: 2px; }

.shell {
  width: min(calc(100% - 40px), var(--page));
  margin: 0 auto;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 82px;
  border-bottom: 1px solid var(--line);
}

.brand-link {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--text);
  font-weight: 760;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.brand-link img {
  width: 42px;
  height: 42px;
  border-radius: 11px;
  box-shadow: 0 8px 24px rgba(27, 83, 213, 0.26);
}

.nav-group, .nav-links, .language-switch {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-links a {
  color: var(--muted);
  padding: 8px 10px;
  border-radius: 10px;
  font-size: 0.93rem;
  text-decoration: none;
}

.nav-links a:hover, .nav-links a[aria-current="page"] {
  color: var(--text);
  background: var(--surface);
}

.language-switch {
  margin-left: 8px;
  padding: 3px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
}

.language-switch button {
  appearance: none;
  border: 0;
  border-radius: 8px;
  padding: 6px 9px;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-size: 0.82rem;
  cursor: pointer;
}

.language-switch button[aria-pressed="true"] {
  background: var(--surface-strong);
  color: var(--text);
  box-shadow: 0 2px 8px rgba(30, 50, 90, 0.14);
}

.hero {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 64px;
  align-items: center;
  padding: 92px 0 72px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--blue);
  font-size: 0.86rem;
  font-weight: 760;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

h1, h2, h3 { line-height: 1.14; letter-spacing: -0.035em; }
h1 { margin: 0; font-size: clamp(3.1rem, 7vw, 6.3rem); }
h2 { margin: 0 0 18px; font-size: clamp(2rem, 4vw, 3.3rem); }
h3 { margin: 0 0 10px; font-size: 1.18rem; }

.lead {
  max-width: 660px;
  margin: 22px 0 0;
  color: var(--muted);
  font-size: clamp(1.08rem, 2vw, 1.3rem);
}

.compatibility-note {
  display: inline-flex;
  margin: 18px 0 0;
  padding: 7px 12px;
  border: 1px solid var(--line);
  border-radius: 11px;
  background: var(--blue-soft);
  color: var(--blue);
  font-size: 0.92rem;
  font-weight: 720;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 20px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--surface-strong);
  color: var(--text);
  font-weight: 690;
  text-decoration: none;
  box-shadow: 0 8px 20px rgba(24, 56, 123, 0.08);
}

.button.primary {
  border-color: transparent;
  background: linear-gradient(135deg, var(--blue), var(--indigo));
  color: #fff;
}

.button.disabled {
  color: var(--muted);
  background: var(--surface);
  cursor: default;
  box-shadow: none;
}

.hero-art {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 390px;
}

.hero-art::before {
  content: "";
  position: absolute;
  width: 320px;
  height: 320px;
  border-radius: 50%;
  background: linear-gradient(135deg, rgba(28, 112, 226, 0.28), rgba(61, 56, 228, 0.24));
  filter: blur(38px);
}

.hero-art img {
  position: relative;
  width: min(72vw, 300px);
  border-radius: 31%;
  box-shadow: 0 36px 80px rgba(29, 69, 163, 0.34);
}

.badge-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.badge {
  padding: 7px 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  background: var(--surface);
  font-size: 0.84rem;
}

.section { padding: 72px 0; }
.section-intro { max-width: 680px; margin-bottom: 30px; color: var(--muted); }

.grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }

.card, .document-card, .notice {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}

.card { padding: 26px; }
.card p, .document-card p, .document-card li { color: var(--muted); }

.icon-chip {
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  margin-bottom: 22px;
  border-radius: 12px;
  background: var(--blue-soft);
  color: var(--blue);
  font-weight: 800;
}

.page-hero { padding: 72px 0 34px; }
.page-hero h1 { font-size: clamp(2.6rem, 6vw, 5rem); }

.document {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 260px;
  gap: 28px;
  align-items: start;
  padding-bottom: 80px;
}

.document-card { padding: clamp(24px, 4vw, 46px); }
.document-card section + section { margin-top: 44px; padding-top: 36px; border-top: 1px solid var(--line); }
.document-card ul, .document-card ol { padding-left: 1.3rem; }
.document-card li + li { margin-top: 9px; }

.side-card {
  position: sticky;
  top: 24px;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--surface);
}

.side-card p { margin: 0; color: var(--muted); font-size: 0.9rem; }
.side-card p + p { margin-top: 12px; }

.notice {
  padding: 22px 24px;
  margin: 24px 0;
  box-shadow: none;
}

.notice strong { color: var(--blue); }

.steps { counter-reset: steps; list-style: none; padding: 0 !important; }
.steps li { position: relative; padding-left: 50px; min-height: 36px; }
.steps li::before {
  counter-increment: steps;
  content: counter(steps);
  position: absolute;
  left: 0;
  top: -3px;
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: var(--blue-soft);
  color: var(--blue);
  font-weight: 780;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  padding: 34px 0 54px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.88rem;
}

.site-footer p { margin: 0; }

code {
  padding: 0.12em 0.34em;
  border-radius: 6px;
  background: var(--blue-soft);
  color: var(--text);
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
}

[hidden] { display: none !important; }

@media (max-width: 860px) {
  .site-header { align-items: flex-start; padding: 18px 0; }
  .nav-group { align-items: flex-end; flex-direction: column-reverse; }
  .nav-links { flex-wrap: wrap; justify-content: flex-end; }
  .hero { grid-template-columns: 1fr; gap: 18px; padding-top: 62px; }
  .hero-art { grid-row: 1; min-height: 250px; }
  .hero-art img { width: 205px; }
  .grid { grid-template-columns: 1fr; }
  .document { grid-template-columns: 1fr; }
  .side-card { position: static; }
}

@media (max-width: 600px) {
  .shell { width: min(calc(100% - 28px), var(--page)); }
  .site-header { display: block; }
  .nav-group { align-items: stretch; margin-top: 16px; }
  .nav-links { justify-content: flex-start; overflow-x: auto; flex-wrap: nowrap; }
  .nav-links a { white-space: nowrap; }
  .language-switch { align-self: flex-start; margin-left: 0; }
  .hero { padding-top: 46px; }
  .hero-art { min-height: 220px; }
  .hero-art img { width: 180px; }
  .site-footer { flex-direction: column; }
}