:root {
  --bg: #f3f5fa;
  --surface: #ffffff;
  --border: #e2e8f0;
  --text: #0f172a;
  --muted: #64748b;
  --accent: #4f46e5;
  --accent-strong: #4338ca;
  --accent-soft: #eef2ff;
  --radius: 14px;
  --font: "Noto Sans", "Segoe UI", system-ui, -apple-system, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0b1020;
    --surface: #131a2e;
    --border: #232c45;
    --text: #e6e9f2;
    --muted: #94a0bb;
    --accent: #8b8cf8;
    --accent-strong: #a5a6fb;
    --accent-soft: #1d2343;
  }
}

:root[data-theme="dark"] {
  --bg: #0b1020;
  --surface: #131a2e;
  --border: #232c45;
  --text: #e6e9f2;
  --muted: #94a0bb;
  --accent: #8b8cf8;
  --accent-strong: #a5a6fb;
  --accent-soft: #1d2343;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

.wrap {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 16px;
}

header.top {
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}

header.top .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 64px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text);
  text-decoration: none;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: 9px;
  background: var(--accent);
  color: #fff;
  font-size: 0.85rem;
  letter-spacing: 0.02em;
}

nav.top-nav { display: flex; gap: 18px; font-size: 0.95rem; }
nav.top-nav a { color: var(--muted); text-decoration: none; }
nav.top-nav a:hover { color: var(--text); }

.hero { padding: 64px 0 40px; }

.hero h1 {
  font-size: clamp(1.8rem, 4.5vw, 2.6rem);
  line-height: 1.2;
  margin: 0 0 16px;
  max-width: 22ch;
  text-wrap: balance;
}

.hero p.lead {
  font-size: 1.1rem;
  color: var(--muted);
  max-width: 60ch;
  margin: 0;
}

section { padding: 28px 0; }

section h2 {
  font-size: 1.3rem;
  margin: 0 0 16px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

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

.card h3 { margin: 0 0 6px; font-size: 1.02rem; }
.card p { margin: 0; color: var(--muted); }

.steps {
  counter-reset: step;
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 12px;
}

.steps li {
  counter-increment: step;
  display: flex;
  gap: 14px;
  align-items: flex-start;
}

.steps li::before {
  content: counter(step);
  flex: none;
  display: grid;
  place-items: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 700;
  font-size: 0.9rem;
}

.note {
  background: var(--accent-soft);
  border-radius: var(--radius);
  padding: 16px 20px;
}

.note p { margin: 0; }

.prose { max-width: 70ch; }
.prose h2 { margin-top: 32px; }
.prose ul { padding-left: 20px; }
.prose li { margin: 4px 0; }

footer {
  margin-top: 40px;
  border-top: 1px solid var(--border);
  padding: 24px 0 40px;
  color: var(--muted);
  font-size: 0.9rem;
}

footer .wrap {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  justify-content: space-between;
}

[lang="en"] { color: var(--muted); }

@media (max-width: 480px) {
  nav.top-nav { gap: 12px; font-size: 0.9rem; }
  .hero { padding: 40px 0 24px; }
}