:root {
  color-scheme: light;
  --bg: #f7f8fa;
  --card: #ffffff;
  --text: #1f2937;
  --muted: #4b5563;
  --border: #e5e7eb;
  --accent: #2563eb;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

.container {
  width: min(900px, 92vw);
  margin: 0 auto;
}

header {
  border-bottom: 1px solid var(--border);
  background: var(--card);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 0;
}

.brand {
  font-weight: 700;
  text-decoration: none;
  color: var(--text);
}

nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
}

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

nav a:hover,
a.link:hover {
  color: var(--accent);
}

main {
  padding: 2.5rem 0;
}

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

h1 {
  margin-top: 0;
  font-size: clamp(1.6rem, 2.5vw, 2.2rem);
  line-height: 1.2;
}

h2 {
  margin: 1.2rem 0 0.5rem;
  font-size: 1.2rem;
}

p {
  margin: 0.5rem 0 1rem;
  color: var(--muted);
}

ul {
  margin: 0.4rem 0 1rem 1.2rem;
  padding: 0;
}

.link {
  color: var(--accent);
}

.disclaimer {
  margin-top: 1rem;
  padding: 0.75rem 0.9rem;
  border-left: 4px solid var(--accent);
  background: #eff6ff;
  color: #1e3a8a;
  border-radius: 8px;
}

footer {
  border-top: 1px solid var(--border);
  color: var(--muted);
  padding: 1rem 0 2rem;
  font-size: 0.95rem;
}

@media (max-width: 640px) {
  .header-inner {
    flex-direction: column;
    align-items: flex-start;
  }
}