:root {
  --navy: #0f2b48;
  --deep: #0d2137;
  --leaf: #4ade80;
  --cyan: #38bdf8;
  --text: #0f2b48;
  --muted: #4b5d73;
  --bg: #ffffff;
  --panel: #f3f7fb;
  --border: #dbe4ee;
}
@media (prefers-color-scheme: dark) {
  :root {
    --text: #e8eef5;
    --muted: #a9b8c9;
    --bg: #0d2137;
    --panel: #12304f;
    --border: #1f4266;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}
a { color: inherit; }
.wrap { max-width: 860px; margin: 0 auto; padding: 0 20px; }

header.site {
  background: var(--deep);
  color: #fff;
}
header.site .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding-top: 14px; padding-bottom: 14px; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; font-weight: 700; letter-spacing: 2px; }
.brand img { width: 32px; height: 32px; }
.brand .iq { color: var(--cyan); }
nav a { color: #d6e4f2; text-decoration: none; margin-left: 18px; font-size: 15px; }
nav a:hover, nav a[aria-current='page'] { color: #fff; text-decoration: underline; }

.hero {
  background: radial-gradient(circle at 50% 30%, #1b4a72 0%, var(--navy) 50%, var(--deep) 100%);
  color: #fff;
  text-align: center;
  padding: 48px 0 56px;
}
.hero img { width: min(240px, 60vw); height: auto; filter: drop-shadow(0 0 24px rgba(74, 222, 128, 0.35)); }
.hero h1 { margin: 18px 0 0; font-size: clamp(36px, 8vw, 56px); letter-spacing: 4px; line-height: 1.1; }
.hero h1 .iq { color: var(--cyan); }
.hero .sub { font-weight: 700; letter-spacing: 8px; font-size: clamp(16px, 4vw, 22px); margin-top: 6px; }
.hero .slogan { color: var(--leaf); letter-spacing: 4px; font-size: 14px; margin-top: 14px; }
.hero p.lead { max-width: 560px; margin: 22px auto 0; font-size: 18px; color: #d6e4f2; }
.badges { margin-top: 26px; display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.badge { display: inline-block; border: 1px solid rgba(255, 255, 255, 0.35); border-radius: 10px; padding: 10px 18px; font-size: 15px; color: #fff; text-decoration: none; }
.badge small { display: block; font-size: 11px; opacity: 0.8; }
.play-badge { display: block; height: 58px; width: auto; }
.badges a { display: inline-flex; align-items: center; }
a.card { display: block; text-decoration: none; }
a.card:hover h3 { text-decoration: underline; }
article.doc .example { background: var(--panel); border-left: 4px solid var(--cyan); border-radius: 6px; padding: 10px 14px; }
article.doc details { margin: 8px 0 0; }
article.doc summary { cursor: pointer; color: var(--muted); }
.cta { margin-top: 36px; background: var(--panel); border: 1px solid var(--border); border-radius: 12px; padding: 18px; }
.cta p { margin-top: 0; }

section { padding: 40px 0; }
h2 { font-size: 26px; margin: 0 0 14px; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 14px; }
.card { background: var(--panel); border: 1px solid var(--border); border-radius: 12px; padding: 16px; }
.card h3 { margin: 0 0 4px; font-size: 17px; }
.card p { margin: 0; color: var(--muted); font-size: 15px; }
.note { color: var(--muted); font-size: 14px; }

article.doc { padding: 32px 0 48px; }
article.doc h1 { font-size: 32px; margin: 0 0 6px; }
article.doc h2 { font-size: 21px; margin: 30px 0 8px; }
article.doc p, article.doc li { font-size: 16px; }
article.doc .meta { color: var(--muted); margin-top: 0; }

footer.site { border-top: 1px solid var(--border); padding: 22px 0 30px; color: var(--muted); font-size: 14px; }
footer.site a { margin-right: 16px; }

@media (max-width: 520px) {
  nav a { margin-left: 12px; font-size: 14px; }
  .brand span.word { display: none; }
}