:root {
  --bg: #f7f8fa;
  --surface: #ffffff;
  --text: #1a1d26;
  --muted: #5c6578;
  --border: #e4e7ee;
  --accent: #1a237e;
  --accent-soft: #e8eaf6;
  --max: 720px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
}

a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 2px;
}

a:hover {
  text-decoration-thickness: 2px;
}

.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 1rem 1.25rem;
  position: sticky;
  top: 0;
  z-index: 10;
}

.site-header-inner {
  max-width: var(--max);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand {
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--accent);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.nav {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
}

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

main {
  max-width: var(--max);
  margin: 0 auto;
  padding: 2rem 1.25rem 4rem;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 2rem 1.5rem;
}

@media (min-width: 640px) {
  .card {
    padding: 2.5rem 2.25rem;
  }
}

h1 {
  margin: 0 0 0.35rem;
  font-size: 1.75rem;
  letter-spacing: -0.03em;
  line-height: 1.25;
}

.meta {
  margin: 0 0 1.75rem;
  color: var(--muted);
  font-size: 0.9rem;
}

h2 {
  margin: 2rem 0 0.65rem;
  font-size: 1.15rem;
  letter-spacing: -0.02em;
}

h2:first-of-type {
  margin-top: 0;
}

p,
ul {
  margin: 0 0 0.9rem;
}

ul {
  padding-left: 1.25rem;
}

li {
  margin-bottom: 0.35rem;
}

li::marker {
  color: var(--muted);
}

.home-hero h1 {
  margin-bottom: 0.5rem;
}

.home-hero p {
  color: var(--muted);
  margin-bottom: 1.5rem;
}

.link-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 0.75rem;
}

.link-list a {
  display: block;
  padding: 1rem 1.15rem;
  background: var(--accent-soft);
  border-radius: 10px;
  text-decoration: none;
  color: var(--accent);
  font-weight: 600;
}

.link-list a:hover {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
}

.link-list span {
  display: block;
  margin-top: 0.25rem;
  font-weight: 400;
  font-size: 0.875rem;
  color: var(--muted);
}

.site-footer {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 1.25rem 2.5rem;
  color: var(--muted);
  font-size: 0.85rem;
}

.site-footer p {
  margin: 0;
}