/* Reset e base */
* { box-sizing: border-box; }
html, body { height: 100%; }
:root {
  --bg: #0b0c10;
  --card: #111318;
  --text: #e6e6e6;
  --muted: #b9c0d0;
  --primary: #4f8cff;
  --border: #1d2230;
  color-scheme: dark light;
}
@media (prefers-color-scheme: light) {
  :root {
    --bg: #ffffff;
    --card: #f7f8fa;
    --text: #111827;
    --muted: #4b5563;
    --primary: #1d4ed8;
    --border: #e5e7eb;
  }
}
body {
  margin: 0;
  font-family: 'Inter', system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
  background: radial-gradient(1200px 600px at 10% -10%, rgba(79,140,255,0.18), transparent 40%),
              radial-gradient(1000px 500px at 110% 10%, rgba(49,46,129,0.18), transparent 40%),
              var(--bg);
  color: var(--text);
  line-height: 1.6;
}

.container {
  width: min(1100px, 92%);
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  backdrop-filter: saturate(180%) blur(8px);
  background: linear-gradient(to bottom, rgba(0,0,0,0.24), rgba(0,0,0,0.0)), var(--bg);
  border-bottom: 1px solid var(--border);
  z-index: 10;
}
.site-header .container {
  padding: 22px 0;
}
.title {
  margin: 0;
  font-size: clamp(1.5rem, 1.2rem + 1.2vw, 2.25rem);
}
.subtitle {
  margin: 6px 0 0 0;
  color: var(--muted);
  font-size: clamp(0.95rem, 0.85rem + 0.4vw, 1.1rem);
}

.card {
  margin: 28px 0 40px 0;
  padding: 18px;
  background: color-mix(in oklab, var(--card) 92%, transparent);
  border: 1px solid var(--border);
  border-radius: 16px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.18);
}

.doc-embed {
  aspect-ratio: 8.5 / 11.7; /* A4-ish for docs */
  width: 100%;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--border);
  background: var(--card);
}
.doc-embed iframe {
  width: 100%;
  height: 100%;
  border: 0;
}

.embed-help {
  margin-top: 14px;
  color: var(--muted);
  font-size: 0.95rem;
}
.link {
  color: var(--primary);
  text-decoration: none;
}
.link:hover { text-decoration: underline; }

.site-footer {
  border-top: 1px solid var(--border);
  padding: 24px 0 40px;
  color: var(--muted);
}