:root {
  --primary: #2b6cb0;
  --primary-light: #8bb3f1;
  --teal: #38b2ac;
  --bg: #f5f6f8;
  --surface: #ffffff;
  --text: #1c1f24;
  --text-secondary: #5c6570;
  --muted: #7b8591;
  --border: #e1e4ea;
  --shadow: 0 12px 30px rgba(36, 74, 128, 0.08);
  --status-ok: #2f9e6f;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  font-family: 'SF Pro Display', 'PingFang SC', 'Helvetica Neue', 'Segoe UI', 'Microsoft YaHei', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
}

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

a:hover,
a:focus {
  text-decoration: underline;
}

.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 20px;
}

.status-banner {
  text-align: center;
  padding: 8px 16px;
  font-size: 14px;
  background: rgba(43, 108, 176, 0.08);
  color: var(--primary);
  border-bottom: 1px solid var(--border);
}

.status-maintenance {
  background: rgba(234, 154, 58, 0.2);
  color: #a45a0b;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid var(--border);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  color: var(--text);
  font-size: 18px;
}

.brand .logo {
  width: 36px;
  height: 36px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  background: linear-gradient(135deg, var(--primary), var(--teal));
  color: #fff;
}

.nav a {
  margin-left: 16px;
  font-size: 14px;
  color: var(--text-secondary);
}

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

main section {
  padding: 56px 0;
}

.hero {
  background: linear-gradient(180deg, #f8fbff 0%, #f5f7fa 60%, #f5f6f8 100%);
}

.hero-inner {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 32px;
  align-items: center;
}

.eyebrow {
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--text-secondary);
  text-transform: uppercase;
  margin-bottom: 12px;
}

.hero h1 {
  font-size: clamp(28px, 4vw, 42px);
  line-height: 1.3;
  margin: 0 0 16px;
}

.subtitle {
  color: var(--text-secondary);
  margin: 0 0 20px;
}

.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 16px;
}

.chip {
  padding: 6px 14px;
  border-radius: 999px;
  background: rgba(43, 108, 176, 0.12);
  color: var(--primary);
  font-size: 13px;
  font-weight: 600;
}

.cta-group {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 16px;
}

.ios-note {
  font-size: 13px;
  color: var(--text-secondary);
  align-self: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 20px;
  border-radius: 22px;
  font-weight: 600;
  border: 1px solid transparent;
  transition: transform 0.15s ease, box-shadow 0.2s ease;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--teal));
  color: #fff;
  box-shadow: 0 10px 25px rgba(43, 108, 176, 0.25);
}

.btn-secondary {
  border-color: var(--primary);
  color: var(--primary);
  background: transparent;
}

.btn:hover {
  transform: translateY(-1px);
}

.hero-note {
  font-size: 14px;
  border-radius: 16px;
  padding: 12px 16px;
  background: rgba(56, 178, 172, 0.12);
  color: var(--text-secondary);
}

.device-card {
  background: var(--surface);
  border-radius: 28px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  padding: 20px;
}

.device-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 600;
  margin-bottom: 12px;
}

.device-body {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.device-item {
  padding: 12px;
  border-radius: 16px;
  background: rgba(43, 108, 176, 0.06);
}

.device-label {
  margin: 0;
  font-size: 13px;
  color: var(--text-secondary);
}

.device-value {
  margin: 4px 0 0;
  font-weight: 600;
}

.contrast {
  background: linear-gradient(180deg, #f5f6f8 0%, #ffffff 100%);
}

.compare-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
}

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

.compare-card.highlight {
  border-color: rgba(56, 178, 172, 0.5);
  box-shadow: 0 14px 35px rgba(56, 178, 172, 0.15);
}

.chaos {
  background: #f1f4f9;
}

.raw-note,
.structured-card {
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 20px;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.structured-card ul {
  padding-left: 20px;
}

.caption {
  margin-top: 12px;
  font-size: 13px;
  color: var(--text-secondary);
}

.memory {
  background: var(--surface);
}

.memory-chain {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
  margin-top: 24px;
}

.memory-item {
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 16px;
  background: #f7f9fd;
}

.memory-item.highlight {
  border-color: rgba(43, 108, 176, 0.5);
  background: rgba(43, 108, 176, 0.08);
}

.tag {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 999px;
  background: rgba(43, 108, 176, 0.12);
  color: var(--primary);
  font-size: 12px;
  margin-bottom: 8px;
}

.quote-card {
  border-radius: 22px;
  border: 1px solid var(--border);
  padding: 24px;
  background: var(--surface);
  box-shadow: var(--shadow);
  font-size: 16px;
  line-height: 1.8;
  color: var(--text);
}

.quote-card cite {
  display: block;
  margin-top: 16px;
  font-size: 14px;
  color: var(--text-secondary);
}

.science-figure {
  border: 1px dashed var(--border);
  border-radius: 18px;
  padding: 18px;
  background: rgba(43, 108, 176, 0.05);
  font-size: 15px;
  color: var(--text-secondary);
}

.science-links {
  margin-top: 16px;
}

.science-links ul {
  margin: 10px 0;
  padding-left: 18px;
}

.anti {
  background: #f7f9ff;
}

.pledge {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 28px;
  align-items: start;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

.card,
.concept-card,
.safety-card,
.contact-card {
  background: var(--surface);
  border-radius: 20px;
  border: 1px solid var(--border);
  padding: 20px;
  box-shadow: var(--shadow);
}

.card h3 {
  margin-top: 0;
}

.note {
  border-radius: 16px;
  padding: 14px 16px;
  background: rgba(234, 154, 58, 0.12);
  color: var(--text);
}

.bullets {
  padding-left: 20px;
  margin: 16px 0;
}

.section-subtitle {
  margin: 8px 0 24px;
  color: var(--text-secondary);
  font-size: 15px;
}

.steps {
  margin: 24px 0 0;
  padding-left: 20px;
}

.steps li {
  margin-bottom: 14px;
  color: var(--text-secondary);
}

.text-link {
  display: inline-block;
  margin-right: 12px;
  font-weight: 600;
}

.safety-card .hash {
  font-size: 13px;
  color: var(--text-secondary);
  margin-top: 12px;
}

.safety-card code {
  display: block;
  background: #f0f3f7;
  padding: 8px;
  border-radius: 12px;
}

details {
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 12px 16px;
  margin-bottom: 12px;
  background: var(--surface);
}

details summary {
  cursor: pointer;
  font-weight: 600;
}

.timeline {
  list-style: none;
  padding: 0;
  margin: 16px 0 0;
}

.timeline li {
  padding: 12px 0;
  border-bottom: 1px solid var(--border);
}

.badge {
  padding: 4px 10px;
  border-radius: 999px;
  font-size: 12px;
  background: rgba(43, 108, 176, 0.12);
  color: var(--primary);
}

.badge-ok {
  background: rgba(47, 158, 111, 0.12);
  color: var(--status-ok);
}

.site-footer {
  background: #f0f3f7;
  border-top: 1px solid var(--border);
  padding: 36px 0;
  font-size: 14px;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

.footer-grid .links {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

@media (max-width: 720px) {
  .site-header .container {
    flex-direction: column;
    gap: 8px;
    height: auto;
    padding: 12px 20px;
  }

  .nav a {
    margin-left: 0;
    margin-right: 12px;
  }

  .hero-inner {
    grid-template-columns: 1fr;
  }

  .cta-group {
    flex-direction: column;
  }

  .btn {
    width: 100%;
    justify-content: center;
  }
}