*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg: #0f0f0f;
  --surface: #1a1a1a;
  --border: #2a2a2a;
  --text: #f0f0f0;
  --muted: #888;
  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --font: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

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

/* ── Nav ── */
nav {
  border-bottom: 1px solid var(--border);
  background: var(--bg);
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.02em;
}

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

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.nav-links a {
  color: var(--muted);
  font-size: 0.9rem;
}

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

/* ── Buttons ── */
.btn-primary {
  background: var(--accent);
  color: #fff !important;
  padding: 0.45rem 1rem;
  border-radius: 6px;
  font-size: 0.875rem;
  font-weight: 500;
  transition: background 0.15s;
}

.btn-primary:hover {
  background: var(--accent-hover) !important;
  color: #fff !important;
}

.btn-large {
  padding: 0.75rem 1.75rem;
  font-size: 1rem;
  border-radius: 8px;
}

/* ── Main / Page layout ── */
main {
  flex: 1;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ── Hero ── */
.hero {
  padding: 6rem 1.5rem 5rem;
  text-align: center;
  max-width: 780px;
  margin: 0 auto;
}

.hero h1 {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.03em;
  margin-bottom: 1.25rem;
}

.hero p {
  font-size: 1.125rem;
  color: var(--muted);
  max-width: 560px;
  margin: 0 auto 2rem;
}

.hero-note {
  font-size: 0.8rem;
  color: var(--muted);
  margin-top: 1rem;
}

/* ── Features ── */
.features {
  padding: 4rem 1.5rem 5rem;
  max-width: 1100px;
  margin: 0 auto;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.25rem;
  margin-top: 1rem;
}

.feature-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.75rem 1.5rem;
}

.feature-icon {
  font-size: 1.75rem;
  margin-bottom: 0.75rem;
}

.feature-card h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.4rem;
}

.feature-card p {
  font-size: 0.875rem;
  color: var(--muted);
  line-height: 1.55;
}

/* ── Page header (for inner pages) ── */
.page-header {
  padding: 4rem 1.5rem 3rem;
  max-width: 780px;
  margin: 0 auto;
}

.page-header h1 {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 0.5rem;
}

.page-header .updated {
  font-size: 0.8rem;
  color: var(--muted);
  margin-bottom: 2rem;
}

/* ── Prose (inner page content) ── */
.prose {
  max-width: 780px;
  margin: 0 auto;
  padding: 0 1.5rem 5rem;
}

.prose h2 {
  font-size: 1.2rem;
  font-weight: 700;
  margin: 2.5rem 0 0.75rem;
  color: var(--text);
}

.prose p {
  color: var(--muted);
  margin-bottom: 1rem;
  font-size: 0.95rem;
}

.prose ul {
  color: var(--muted);
  padding-left: 1.5rem;
  margin-bottom: 1rem;
  font-size: 0.95rem;
}

.prose ul li {
  margin-bottom: 0.3rem;
}

.prose a {
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ── Setup page ── */
.setup-steps {
  max-width: 780px;
  margin: 0 auto;
  padding: 0 1.5rem 5rem;
}

.step {
  display: flex;
  gap: 1.25rem;
  margin-bottom: 2rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border);
}

.step:last-child {
  border-bottom: none;
}

.step-num {
  flex-shrink: 0;
  width: 2rem;
  height: 2rem;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-size: 0.85rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 0.1rem;
}

.step-body h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.4rem;
}

.step-body p {
  font-size: 0.875rem;
  color: var(--muted);
}

.notice {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.25rem 1.5rem;
  margin-bottom: 2.5rem;
  font-size: 0.875rem;
  color: var(--muted);
}

.notice strong {
  color: var(--text);
}

/* ── About ── */
.about-body {
  max-width: 780px;
  margin: 0 auto;
  padding: 0 1.5rem 5rem;
}

.about-body p {
  color: var(--muted);
  font-size: 0.975rem;
  margin-bottom: 1.25rem;
  line-height: 1.7;
}

/* ── Footer ── */
footer {
  border-top: 1px solid var(--border);
  padding: 1.5rem;
}

.footer-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  font-size: 0.8rem;
  color: var(--muted);
}

.footer-links {
  display: flex;
  gap: 1.25rem;
}

.footer-links a {
  color: var(--muted);
}

.footer-links a:hover {
  color: var(--text);
}

/* ── Responsive ── */
@media (max-width: 600px) {
  .nav-links {
    gap: 1rem;
  }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }
}