:root {
  --bg: #0f1115;
  --surface: #171a21;
  --border: #262b36;
  --text: #e6e8ec;
  --muted: #9aa1ad;
  --accent: #6ea8fe;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #ffffff;
    --surface: #f5f6f8;
    --border: #e1e4e9;
    --text: #16181d;
    --muted: #5d6673;
    --accent: #1a56db;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.65 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

header {
  position: sticky;
  top: 0;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

nav {
  max-width: 880px;
  margin: 0 auto;
  padding: 14px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo { font-size: 18px; letter-spacing: -0.02em; }
.logo b { color: var(--accent); }

nav ul {
  list-style: none;
  display: flex;
  gap: 22px;
  margin: 0;
  padding: 0;
}

nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 15px;
}

nav a:hover { color: var(--text); }

main {
  max-width: 880px;
  margin: 0 auto;
  padding: 0 20px;
}

section { padding: 56px 0; }
section + section { border-top: 1px solid var(--border); }

.hero { padding: 88px 0 64px; }

h1 {
  font-size: clamp(32px, 6vw, 52px);
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin: 0 0 16px;
}

.accent { color: var(--accent); }

h2 {
  font-size: 26px;
  letter-spacing: -0.02em;
  margin: 0 0 14px;
}

h3 { font-size: 17px; margin: 0 0 6px; }

.lead {
  font-size: 19px;
  color: var(--muted);
  max-width: 60ch;
  margin: 0 0 28px;
}

button {
  background: var(--accent);
  color: #fff;
  border: 0;
  border-radius: 8px;
  padding: 11px 22px;
  font-size: 15px;
  font-weight: 500;
  cursor: pointer;
}

button:hover { filter: brightness(1.1); }

.out {
  min-height: 1.65em;
  margin: 14px 0 0;
  color: var(--muted);
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
}

.card p { color: var(--muted); margin: 0; }

a { color: var(--accent); }

footer {
  border-top: 1px solid var(--border);
  padding: 28px 20px;
  text-align: center;
  color: var(--muted);
  font-size: 14px;
}