:root {
  --bg: #fafafa;
  --surface: #ffffff;
  --text: #1a1a1a;
  --muted: #6b7280;
  --accent: #f59e0b;
  --border: #e5e7eb;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b0b0c;
    --surface: #151517;
    --text: #f3f4f6;
    --muted: #9ca3af;
    --accent: #fbbf24;
    --border: #27272a;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 17px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

.site-header {
  position: sticky;
  top: 0;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background: color-mix(in srgb, var(--bg) 80%, transparent);
  border-bottom: 1px solid var(--border);
  z-index: 10;
}

.site-header .inner {
  max-width: 720px;
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.brand {
  font-weight: 700;
  font-size: 15px;
  letter-spacing: -0.01em;
  color: var(--text);
  text-decoration: none;
}

.brand span { color: var(--accent); }

nav { display: flex; gap: 18px; }

nav a {
  font-size: 14px;
  font-weight: 500;
  color: var(--muted);
  text-decoration: none;
  transition: color 0.15s ease;
}

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

main {
  max-width: 720px;
  margin: 0 auto;
  padding: 48px 24px 96px;
}

h1 {
  font-size: 38px;
  line-height: 1.15;
  letter-spacing: -0.02em;
  font-weight: 800;
  margin: 0 0 8px;
}

.last-updated {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--muted);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 4px 12px;
  margin: 8px 0 32px;
}

h2 {
  font-size: 24px;
  letter-spacing: -0.015em;
  font-weight: 700;
  margin: 48px 0 12px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

h3 { font-size: 19px; font-weight: 700; margin: 32px 0 8px; }
h4 { font-size: 16px; font-weight: 700; margin: 24px 0 6px; }

p { margin: 0 0 16px; color: var(--text); }

ul { padding-left: 22px; margin: 0 0 16px; }
li { margin-bottom: 8px; }
li p { margin-bottom: 8px; }

a { color: var(--accent); text-decoration: none; font-weight: 500; }
a:hover { text-decoration: underline; }

strong { font-weight: 650; }

.site-footer {
  max-width: 720px;
  margin: 0 auto;
  padding: 24px;
  border-top: 1px solid var(--border);
  font-size: 13px;
  color: var(--muted);
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}

.site-footer a { color: var(--muted); }
.site-footer a:hover { color: var(--text); }

.contact-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 28px;
  margin-top: 24px;
}

.contact-card h2 { border: none; margin: 0 0 8px; padding: 0; }

.btn {
  display: inline-block;
  background: var(--accent);
  color: #111;
  font-weight: 700;
  font-size: 15px;
  padding: 12px 22px;
  border-radius: 999px;
  margin-top: 8px;
}

.btn:hover { text-decoration: none; filter: brightness(1.05); }