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

html {
  font-size: 17px;
  line-height: 1.65;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  padding: 0 1rem;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: #1a1a1a;
  background: #ffffff;
}

.site-wrap {
  max-width: 680px;
  margin: 0 auto;
  padding: 2.5rem 0 4rem;
}

/* ── Header ──────────────────────────────────────────────────────────────── */

.site-header {
  margin-bottom: 2.5rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid #e5e5e5;
}

.site-header h1 {
  margin: 0 0 0.25rem;
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.site-header h1 a {
  color: inherit;
  text-decoration: none;
}

.site-nav {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  gap: 1.25rem;
}

.site-nav a {
  font-size: 0.9rem;
  color: #555;
  text-decoration: none;
}

.site-nav a:hover {
  color: #1a1a1a;
  text-decoration: underline;
}

/* ── Main content ─────────────────────────────────────────────────────────── */

main h1 {
  margin: 0 0 0.5rem;
  font-size: 2rem;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

main h2 {
  margin: 2rem 0 0.5rem;
  font-size: 1.1rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

main h3 {
  margin: 1.5rem 0 0.35rem;
  font-size: 1rem;
  font-weight: 600;
}

main p {
  margin: 0 0 1rem;
}

main ul, main ol {
  margin: 0 0 1rem;
  padding-left: 1.5rem;
}

main li {
  margin-bottom: 0.3rem;
}

main a {
  color: #0070f3;
  text-decoration: underline;
  text-underline-offset: 2px;
}

main a:hover {
  color: #0050c0;
}

.page-meta {
  margin: 0 0 2rem;
  font-size: 0.85rem;
  color: #777;
}

.notice {
  margin: 1.5rem 0;
  padding: 0.85rem 1rem;
  background: #fffbe6;
  border-left: 3px solid #f5a623;
  font-size: 0.9rem;
  line-height: 1.55;
}

/* ── Landing page hero ────────────────────────────────────────────────────── */

.hero {
  margin: 2rem 0 3rem;
}

.hero h1 {
  margin-bottom: 0.75rem;
}

.hero p {
  font-size: 1.1rem;
  color: #444;
  max-width: 540px;
}

.hero-links {
  margin-top: 2rem;
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  padding: 0.5rem 1.1rem;
  border: 1px solid #ccc;
  border-radius: 6px;
  font-size: 0.9rem;
  color: #333;
  text-decoration: none;
  background: #f9f9f9;
  transition: background 0.15s, border-color 0.15s;
}

.btn:hover {
  background: #f0f0f0;
  border-color: #aaa;
  color: #111;
  text-decoration: none;
}

/* ── Footer ──────────────────────────────────────────────────────────────── */

.site-footer {
  margin-top: 3rem;
  padding-top: 1rem;
  border-top: 1px solid #e5e5e5;
  font-size: 0.8rem;
  color: #999;
}