:root {
  --bg: #f8fafc;
  --surface: #ffffff;
  --border: #e2e8f0;
  --text: #0f172a;
  --muted: #475569;
  --primary: #2563eb;
  --accent: #ea580c;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b1220;
    --surface: #111a2e;
    --border: #1e2a44;
    --text: #e2e8f0;
    --muted: #94a3b8;
    --primary: #60a5fa;
    --accent: #fb923c;
  }
}
* { box-sizing: border-box; }
html { font-size: 16px; }
body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--text);
  font-family: "Noto Sans Thai", "Sarabun", "Thonburi", "Leelawadee UI", system-ui, -apple-system, "Segoe UI", sans-serif;
  line-height: 1.7;
}
main { flex: 1; width: 100%; max-width: 40rem; margin: 0 auto; padding: 3rem 1rem 2rem; }
.brand { font-size: 1.1rem; font-weight: 700; letter-spacing: 0.02em; }
.brand span { color: var(--primary); }
.brand b { color: var(--accent); font-weight: 700; }
h1 { font-size: clamp(1.9rem, 6vw, 2.8rem); line-height: 1.25; margin: 2.5rem 0 1rem; text-wrap: balance; }
h2 { font-size: 1.15rem; margin: 2rem 0 0.4rem; }
p, li { color: var(--muted); }
p { margin: 0.5rem 0; }
.tag { display: inline-block; padding: 0.15rem 0.7rem; border: 1px solid var(--accent); border-radius: 999px; color: var(--accent); font-size: 0.85rem; font-weight: 600; }
.card { margin-top: 2rem; padding: 1rem 1.25rem; background: var(--surface); border: 1px solid var(--border); border-radius: 0.75rem; }
a { color: var(--primary); }
.btn { display: inline-block; margin-top: 0.5rem; padding: 0.6rem 1.2rem; background: var(--primary); color: #fff; border-radius: 0.5rem; text-decoration: none; font-weight: 600; }
footer { padding: 1.5rem 1rem; text-align: center; font-size: 0.85rem; color: var(--muted); border-top: 1px solid var(--border); }
footer a { margin: 0 0.5rem; }
ul { padding-left: 1.25rem; }