:root {
  color-scheme: light dark;
  --page: #f4f5fa;
  --surface: rgba(255, 255, 255, 0.78);
  --text: #17171c;
  --muted: #62636d;
  --line: rgba(20, 20, 30, 0.1);
  --accent: #087cf0;
  --shadow: 0 18px 50px rgba(28, 35, 60, 0.1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --page: #101115;
    --surface: rgba(31, 32, 38, 0.82);
    --text: #f5f5f7;
    --muted: #afb0b8;
    --line: rgba(255, 255, 255, 0.11);
    --accent: #42a5ff;
    --shadow: 0 18px 50px rgba(0, 0, 0, 0.28);
  }
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background:
    radial-gradient(circle at top left, rgba(35, 139, 255, 0.13), transparent 34rem),
    var(--page);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", sans-serif;
  font-size: 17px;
  line-height: 1.64;
}

a {
  color: var(--accent);
  text-underline-offset: 0.18em;
}

.shell {
  width: min(100% - 32px, 920px);
  margin: 0 auto;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 28px 0;
}

.brand {
  color: var(--text);
  font-size: 1.15rem;
  font-weight: 750;
  letter-spacing: -0.02em;
  text-decoration: none;
}

nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 16px;
}

.header-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 18px;
}

.language-picker {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 650;
}

.language-picker select {
  min-height: 40px;
  max-width: 190px;
  padding: 7px 34px 7px 13px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background-color: var(--surface);
  color: var(--text);
  font: inherit;
  font-size: 0.9rem;
  cursor: pointer;
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
}

.language-picker select:hover,
.language-picker select:focus-visible {
  border-color: rgba(35, 139, 255, 0.55);
}

nav a {
  color: var(--muted);
  font-size: 0.94rem;
  font-weight: 650;
  text-decoration: none;
}

nav a:hover,
nav a:focus-visible {
  color: var(--text);
}

main {
  padding: 28px 0 72px;
}

main:focus {
  outline: none;
}

.hero {
  padding: 72px 0 44px;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 750;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  line-height: 1.17;
  letter-spacing: -0.035em;
}

h1 {
  max-width: 760px;
  margin: 0;
  font-size: clamp(2.6rem, 8vw, 5.8rem);
}

.hero p {
  max-width: 650px;
  margin: 22px 0 0;
  color: var(--muted);
  font-size: clamp(1.1rem, 2.6vw, 1.35rem);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  margin-top: 36px;
}

.card,
.document {
  border: 1px solid var(--line);
  border-radius: 28px;
  background: var(--surface);
  box-shadow: var(--shadow);
  backdrop-filter: blur(22px);
  -webkit-backdrop-filter: blur(22px);
}

.card {
  display: block;
  padding: 30px;
  color: var(--text);
  text-decoration: none;
}

.card:hover,
.card:focus-visible {
  border-color: rgba(35, 139, 255, 0.45);
  transform: translateY(-2px);
}

.card h2 {
  margin: 0 0 10px;
  font-size: 1.45rem;
}

.card p {
  margin: 0;
  color: var(--muted);
}

.document {
  padding: clamp(26px, 5vw, 60px);
}

.document h1 {
  font-size: clamp(2.3rem, 7vw, 4.5rem);
}

.meta {
  margin: 22px 0 36px;
  padding-bottom: 28px;
  border-bottom: 1px solid var(--line);
  color: var(--muted);
}

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

.document h2 {
  margin: 46px 0 16px;
  font-size: 2rem;
}

.document h3 {
  margin: 34px 0 10px;
  font-size: 1.3rem;
}

.document p,
.document li {
  color: var(--muted);
}

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

.language-divider {
  margin: 56px 0;
  border: 0;
  border-top: 1px solid var(--line);
}

.notice {
  margin: 24px 0;
  padding: 18px 20px;
  border-left: 4px solid var(--accent);
  border-radius: 14px;
  background: rgba(35, 139, 255, 0.09);
}

footer {
  padding: 26px 0 42px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.9rem;
}

@media (max-width: 680px) {
  header {
    align-items: flex-start;
    flex-direction: column;
  }

  .header-actions {
    width: 100%;
    align-items: flex-start;
    flex-direction: column;
    gap: 14px;
  }

  nav {
    justify-content: flex-start;
  }

  .language-picker {
    width: 100%;
    justify-content: space-between;
  }

  .language-picker select {
    flex: 1;
  }

  .hero {
    padding-top: 44px;
  }

  .card-grid {
    grid-template-columns: 1fr;
  }

  .document {
    border-radius: 22px;
  }
}