:root {
  --bg: #f9fafb;
  --text: #111827;
  --muted: #4b5563;
  --accent: #059669;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #0b1210; --text: #f3f4f6; --muted: #a7b0ad; --accent: #34d399; }
}
* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
body {
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  line-height: 1.5;
}
main {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 48px 16px;
}
.mark { width: 64px; height: 64px; border-radius: 14px; }
.brand {
  margin: 14px 0 0;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--accent);
}
h1 {
  margin: 8px 0 12px;
  font-size: clamp(2rem, 6vw, 3.25rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
}
.lead { margin: 0; max-width: 34rem; font-size: 1.125rem; color: var(--muted); }
footer { padding: 24px 16px; text-align: center; font-size: 0.875rem; color: var(--muted); }