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

:root {
  --blue: #007AFF;
  --blue-dark: #0055D4;
  --gray-50: #F9FAFB;
  --gray-100: #F3F4F6;
  --gray-200: #E5E7EB;
  --gray-400: #9CA3AF;
  --gray-500: #6B7280;
  --gray-600: #4B5563;
  --gray-700: #374151;
  --gray-800: #1F2937;
  --gray-900: #111827;
  --radius: 12px;
  --max-width: 720px;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  color: var(--gray-800);
  background: #fff;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

a:hover {
  text-decoration: underline;
}

/* ── Navigation ─────────────────────────────── */

.nav {
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--gray-200);
  z-index: 100;
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--gray-900);
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-logo img {
  width: 28px;
  height: 28px;
  border-radius: 6px;
}

.nav-links {
  display: flex;
  gap: 24px;
  list-style: none;
}

.nav-links a {
  color: var(--gray-600);
  font-size: 0.875rem;
  font-weight: 500;
  transition: color 0.15s;
}

.nav-links a:hover {
  color: var(--blue);
  text-decoration: none;
}

/* ── Hero ───────────────────────────────────── */

.hero {
  text-align: center;
  padding: 80px 24px 64px;
}

.hero-icon {
  width: 96px;
  height: 96px;
  border-radius: 22px;
  margin-bottom: 24px;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
}

.hero h1 {
  font-size: 2.5rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--gray-900);
  margin-bottom: 12px;
}

.hero p {
  font-size: 1.125rem;
  color: var(--gray-500);
  max-width: 480px;
  margin: 0 auto 32px;
}

.badge-link img {
  height: 48px;
}

/* ── Features ───────────────────────────────── */

.features {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px 80px;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.feature-card {
  background: var(--gray-50);
  border-radius: var(--radius);
  padding: 28px 24px;
}

.feature-icon {
  font-size: 1.75rem;
  margin-bottom: 12px;
}

.feature-card h3 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 6px;
}

.feature-card p {
  font-size: 0.875rem;
  color: var(--gray-500);
  line-height: 1.6;
}

/* ── Page Content (Privacy, Support, Error) ── */

.page {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 48px 24px 80px;
}

.page h1 {
  font-size: 2rem;
  font-weight: 800;
  color: var(--gray-900);
  margin-bottom: 8px;
}

.page .subtitle {
  color: var(--gray-400);
  font-size: 0.875rem;
  margin-bottom: 40px;
}

.page h2 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--gray-900);
  margin-top: 40px;
  margin-bottom: 12px;
}

.page h3 {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--gray-800);
  margin-top: 28px;
  margin-bottom: 8px;
}

.page p,
.page li {
  color: var(--gray-600);
  margin-bottom: 12px;
}

.page ul,
.page ol {
  padding-left: 20px;
}

.page li {
  margin-bottom: 6px;
}

.page table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0 24px;
  font-size: 0.875rem;
}

.page th,
.page td {
  text-align: left;
  padding: 10px 12px;
  border-bottom: 1px solid var(--gray-200);
}

.page th {
  font-weight: 600;
  color: var(--gray-700);
  background: var(--gray-50);
}

.page td {
  color: var(--gray-600);
}

/* ── FAQ ─────────────────────────────────────── */

.faq-item {
  border-bottom: 1px solid var(--gray-200);
  padding: 20px 0;
}

.faq-item:last-child {
  border-bottom: none;
}

.faq-item h3 {
  margin-top: 0;
  margin-bottom: 8px;
}

.faq-item p {
  margin-bottom: 0;
}

/* ── Contact Box ─────────────────────────────── */

.contact-box {
  background: var(--gray-50);
  border-radius: var(--radius);
  padding: 28px 24px;
  margin-top: 40px;
  text-align: center;
}

.contact-box h2 {
  margin-top: 0;
  margin-bottom: 8px;
}

.contact-box p {
  margin-bottom: 16px;
}

.contact-box a.email {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--blue);
}

/* ── Error Page ──────────────────────────────── */

.error-page {
  text-align: center;
  padding: 120px 24px;
}

.error-page h1 {
  font-size: 6rem;
  font-weight: 800;
  color: var(--gray-200);
  margin-bottom: 8px;
}

.error-page h2 {
  margin-top: 0;
  color: var(--gray-700);
}

.error-page p {
  color: var(--gray-500);
  margin-bottom: 24px;
}

.btn {
  display: inline-block;
  background: var(--blue);
  color: #fff;
  font-weight: 600;
  font-size: 0.9375rem;
  padding: 10px 24px;
  border-radius: 8px;
  transition: background 0.15s;
}

.btn:hover {
  background: var(--blue-dark);
  text-decoration: none;
}

/* ── Footer ──────────────────────────────────── */

.footer {
  border-top: 1px solid var(--gray-200);
  padding: 32px 24px;
  text-align: center;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 24px;
  list-style: none;
  margin-bottom: 12px;
}

.footer-links a {
  color: var(--gray-500);
  font-size: 0.875rem;
}

.footer-copy {
  color: var(--gray-400);
  font-size: 0.8125rem;
}

/* ── Responsive ──────────────────────────────── */

@media (max-width: 600px) {
  .hero {
    padding: 56px 20px 48px;
  }

  .hero h1 {
    font-size: 1.875rem;
  }

  .hero p {
    font-size: 1rem;
  }

  .features {
    grid-template-columns: 1fr;
    padding: 0 20px 56px;
  }

  .page {
    padding: 32px 20px 56px;
  }

  .page h1 {
    font-size: 1.625rem;
  }

  .nav-links {
    gap: 16px;
  }
}