:root {
  color-scheme: light dark;
  --background: #f5f7fb;
  --surface: rgba(255, 255, 255, 0.88);
  --text: #172033;
  --muted: #5f687a;
  --line: #dfe4ee;
  --accent: #1769e0;
  --accent-soft: #e8f1ff;
  --shadow: 0 18px 50px rgba(26, 39, 69, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at 10% 0%, rgba(72, 155, 255, 0.15), transparent 34rem),
    var(--background);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", sans-serif;
  line-height: 1.65;
}

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

a:focus-visible {
  border-radius: 0.25rem;
  outline: 3px solid rgba(23, 105, 224, 0.35);
  outline-offset: 3px;
}

.site-header,
.site-footer,
main {
  width: min(100% - 2rem, 920px);
  margin-inline: auto;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-block: 1.25rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  color: var(--text);
  font-size: 1.05rem;
  font-weight: 750;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 2.15rem;
  height: 2.15rem;
  place-items: center;
  border-radius: 0.7rem;
  background: linear-gradient(145deg, #1c7df2, #6546d7);
  box-shadow: 0 8px 22px rgba(58, 91, 207, 0.28);
  color: #fff;
  font-weight: 800;
}

nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0.85rem;
  font-size: 0.92rem;
}

nav a {
  color: var(--muted);
  text-decoration: none;
}

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

main {
  padding-block: 2.5rem 4rem;
}

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

.hero,
.document {
  border-radius: 1.5rem;
  padding: clamp(1.4rem, 4vw, 3.4rem);
}

.eyebrow {
  margin: 0 0 0.65rem;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 750;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  line-height: 1.2;
}

h1 {
  max-width: 18ch;
  margin: 0;
  font-size: clamp(2.25rem, 7vw, 4.4rem);
  letter-spacing: -0.045em;
}

.document h1 {
  max-width: none;
  font-size: clamp(2rem, 5vw, 3.2rem);
}

.lead {
  max-width: 65ch;
  margin: 1.1rem 0 0;
  color: var(--muted);
  font-size: 1.08rem;
}

.meta {
  margin-top: 0.8rem;
  color: var(--muted);
  font-size: 0.9rem;
}

.grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  margin-top: 1rem;
}

.card {
  border-radius: 1.1rem;
  padding: 1.25rem;
}

.card h2 {
  margin: 0;
  font-size: 1.12rem;
}

.card p {
  margin: 0.65rem 0 1rem;
  color: var(--muted);
}

.document section {
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
  margin-top: 1.5rem;
}

.document h2 {
  margin: 0 0 0.75rem;
  font-size: 1.35rem;
  letter-spacing: -0.015em;
}

.document p,
.document li {
  max-width: 74ch;
}

.document ul {
  padding-left: 1.25rem;
}

.notice {
  border-left: 4px solid var(--accent);
  border-radius: 0.65rem;
  margin-top: 1.25rem;
  padding: 0.9rem 1rem;
  background: var(--accent-soft);
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  border-top: 1px solid var(--line);
  padding-block: 1.4rem 2rem;
  color: var(--muted);
  font-size: 0.85rem;
}

@media (max-width: 720px) {
  .site-header,
  .site-footer {
    align-items: flex-start;
    flex-direction: column;
  }

  nav {
    justify-content: flex-start;
  }

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

@media (prefers-color-scheme: dark) {
  :root {
    --background: #0d111b;
    --surface: rgba(20, 27, 42, 0.9);
    --text: #f3f6ff;
    --muted: #b3bdd0;
    --line: #2d374b;
    --accent: #76aaff;
    --accent-soft: #172b4a;
    --shadow: 0 18px 50px rgba(0, 0, 0, 0.25);
  }
}