:root {
  --bg: #f5f5f7;
  --surface: #ffffff;
  --text: #1d1d1f;
  --muted: #6e6e73;
  --line: #d2d2d7;
  --accent: #0071e3;
  --accent-hover: #0077ed;
  --danger: #d70015;
  --ok: #1d8348;
  --radius-lg: 22px;
  --radius-md: 14px;
  --shadow: 0 1px 2px rgba(0,0,0,.04), 0 8px 24px rgba(0,0,0,.06);
  --font: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", Helvetica, Arial, sans-serif;
  --font-display: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Helvetica Neue", Helvetica, Arial, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #000000;
    --surface: #1c1c1e;
    --text: #f5f5f7;
    --muted: #98989d;
    --line: #38383a;
    --accent: #0a84ff;
    --accent-hover: #409cff;
    --danger: #ff453a;
    --ok: #30d158;
    --shadow: 0 1px 2px rgba(0,0,0,.3), 0 8px 24px rgba(0,0,0,.35);
  }
}

:root[data-theme="dark"] {
  --bg: #000000;
  --surface: #1c1c1e;
  --text: #f5f5f7;
  --muted: #98989d;
  --line: #38383a;
  --accent: #0a84ff;
  --accent-hover: #409cff;
  --danger: #ff453a;
  --ok: #30d158;
  --shadow: 0 1px 2px rgba(0,0,0,.3), 0 8px 24px rgba(0,0,0,.35);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  -webkit-font-smoothing: antialiased;
}

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

.topbar {
  position: sticky; top: 0; z-index: 10;
  background: color-mix(in srgb, var(--bg) 80%, transparent);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--line);
}
.topbar-inner {
  max-width: 980px; margin: 0 auto; padding: 0 16px;
  height: 52px; display: flex; align-items: center; justify-content: space-between;
  font-size: 14px;
}
.crumb { color: var(--muted); display: flex; gap: 6px; align-items: center; }
.crumb a { color: var(--accent); }
.brand { font-weight: 600; letter-spacing: -.01em; }

.wrap { max-width: 980px; margin: 0 auto; padding: 0 16px; }

.hero { text-align: center; padding: 56px 0 28px; }
.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(34px, 6vw, 56px);
  font-weight: 600;
  letter-spacing: -.025em;
  line-height: 1.07;
  margin: 0 0 12px;
}
.hero p {
  font-size: clamp(17px, 2.4vw, 21px);
  color: var(--muted);
  margin: 0 auto;
  max-width: 560px;
  line-height: 1.4;
}

.card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: 28px;
}

.footer {
  text-align: center; color: var(--muted); font-size: 12px;
  padding: 40px 16px 56px; line-height: 1.5;
}

@media (max-width: 600px) {
  .card { padding: 20px; border-radius: 18px; }
  .hero { padding: 36px 0 20px; }
}