:root {
  color-scheme: light;
  --background: #f7f8fa;
  --surface: #ffffff;
  --text: #18202b;
  --muted: #566273;
  --accent: #2056a8;
  --accent-dark: #163d78;
  --border: #dce2ea;
  --notice: #eef5ff;
  --max-width: 72rem;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--background);
  color: var(--text);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 1rem;
  line-height: 1.65;
}

a { color: var(--accent); text-underline-offset: 0.18em; }
a:hover, a:focus { color: var(--accent-dark); }
a:focus-visible { outline: 3px solid #84adf0; outline-offset: 3px; }

.site-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1.5rem;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1.25rem 1.5rem;
}

.brand {
  color: var(--text);
  font-size: 1.25rem;
  font-weight: 750;
  text-decoration: none;
}

nav { display: flex; flex-wrap: wrap; gap: 1.25rem; }
nav a { font-weight: 650; }

main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 3rem 1.5rem 5rem;
}

section { margin: 0 0 4rem; }

.hero { padding-top: 4rem; }
.hero h1, .document h1 {
  max-width: 18ch;
  margin: 0 0 1rem;
  font-size: clamp(2.5rem, 8vw, 5rem);
  line-height: 1.05;
  letter-spacing: -0.04em;
}

.eyebrow {
  margin: 0 0 0.8rem;
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 800;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.lead {
  max-width: 48rem;
  color: var(--muted);
  font-size: clamp(1.15rem, 2.5vw, 1.45rem);
}

.notice {
  max-width: 52rem;
  margin-top: 2rem;
  padding: 1.1rem 1.25rem;
  border-left: 4px solid var(--accent);
  background: var(--notice);
}

h2 { margin-top: 0; font-size: clamp(1.55rem, 3vw, 2.15rem); line-height: 1.2; }
h3 { margin: 0 0 0.6rem; font-size: 1.2rem; }
p, li { max-width: 72ch; }

.cards {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.cards article, .cta {
  padding: 1.5rem;
  border: 1px solid var(--border);
  border-radius: 0.8rem;
  background: var(--surface);
}

.cards p { margin-bottom: 0; color: var(--muted); }
.checklist { padding-left: 1.3rem; }
.checklist li { margin-bottom: 0.65rem; }

.button {
  display: inline-block;
  margin-top: 0.5rem;
  padding: 0.7rem 1rem;
  border-radius: 0.45rem;
  background: var(--accent);
  color: #fff;
  font-weight: 750;
  text-decoration: none;
}
.button:hover, .button:focus { background: var(--accent-dark); color: #fff; }

.document { max-width: 52rem; }
.document h1 { font-size: clamp(2.2rem, 6vw, 4rem); }
.document section { margin-bottom: 2.8rem; }
.document h3 { margin-top: 1.5rem; }
.metadata { color: var(--muted); }

footer {
  display: flex;
  justify-content: space-between;
  gap: 1.5rem;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2rem 1.5rem 3rem;
  border-top: 1px solid var(--border);
  color: var(--muted);
}

.error-page { min-height: 70vh; }

@media (max-width: 48rem) {
  .site-header, footer { align-items: flex-start; flex-direction: column; }
  .cards { grid-template-columns: 1fr; }
  .hero { padding-top: 2rem; }
}