:root {
  --bg: #fafaf9;
  --bg-alt: #f1f0ee;
  --text: #1c1b1a;
  --muted: #5f5c58;
  --border: #e2e0dc;
  --accent: #2f5fd0;
  --accent-text: #ffffff;
  --radius: 10px;
  --max: 1040px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #131312;
    --bg-alt: #1b1b1a;
    --text: #ecebe8;
    --muted: #a3a09b;
    --border: #2c2b29;
    --accent: #7ea2ff;
    --accent-text: #0e1220;
  }
}

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; }

.container {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 16px;
}
.narrow { max-width: 680px; }

/* Header */
.site-header {
  position: sticky;
  top: 0;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
  z-index: 10;
}
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}
.logo {
  font-weight: 700;
  letter-spacing: -0.02em;
  text-decoration: none;
  font-size: 1.15rem;
}
.nav nav { display: flex; gap: 20px; }
.nav nav a {
  text-decoration: none;
  color: var(--muted);
  font-size: 0.95rem;
}
.nav nav a:hover { color: var(--text); }

/* Hero */
.hero { padding: 112px 0 96px; }
.hero h1 {
  font-size: clamp(2.2rem, 6vw, 3.8rem);
  line-height: 1.08;
  letter-spacing: -0.03em;
  margin: 0 0 16px;
  max-width: 14ch;
}
.lede {
  font-size: 1.2rem;
  color: var(--muted);
  max-width: 46ch;
  margin: 0 0 32px;
}

.button {
  display: inline-block;
  background: var(--accent);
  color: var(--accent-text);
  padding: 12px 22px;
  border-radius: var(--radius);
  text-decoration: none;
  font-weight: 600;
}
.button:hover { filter: brightness(1.08); }

/* Sections */
.section { padding: 80px 0; }
.section.alt { background: var(--bg-alt); }
.section h2 {
  font-size: 1.8rem;
  letter-spacing: -0.02em;
  margin: 0 0 24px;
}
.section p { color: var(--muted); font-size: 1.05rem; }

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}
.card {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  background: var(--bg);
}
.card h3 { margin: 0 0 8px; font-size: 1.1rem; }
.card p { margin: 0; font-size: 1rem; }

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 32px 0;
  color: var(--muted);
  font-size: 0.9rem;
}
.site-footer p { margin: 0; }

/* 404 */
.notfound {
  min-height: 70vh;
  display: grid;
  place-items: center;
  text-align: center;
}

@media (max-width: 520px) {
  .nav nav { gap: 14px; }
  .hero { padding: 72px 0 64px; }
  .section { padding: 56px 0; }
}