:root {
  color-scheme: light dark;
  --primary: #4f6ef7;
  --primary-dark: #3d5ce6;
  --primary-light: #eef1ff;
  --primary-glow: rgba(79, 110, 247, 0.35);
  --accent: #8b5cf6;
  --text: #0f172a;
  --text-secondary: #64748b;
  --text-tertiary: #94a3b8;
  --bg: #ffffff;
  --bg-alt: #f8fafc;
  --bg-muted: #f8fafc;
  --bg-dark: #0b1120;
  --border: #e2e8f0;
  --surface: #ffffff;
  --surface-elevated: #ffffff;
  --header-bg: rgba(255, 255, 255, 0.82);
  --header-border: rgba(226, 232, 240, 0.8);
  --mobile-bar-bg: rgba(255, 255, 255, 0.96);
  --overlay-panel-bg: #ffffff;
  --device-screen-bg: #f1f5f9;
  --toggle-bar: #0f172a;
  --radius: 16px;
  --radius-lg: 24px;
  --max: 1120px;
  --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 12px 40px rgba(79, 110, 247, 0.12);
  --shadow-lg: 0 24px 64px rgba(15, 23, 42, 0.14);
}

@media (prefers-color-scheme: dark) {
  :root {
    --primary-light: rgba(79, 110, 247, 0.18);
    --primary-glow: rgba(79, 110, 247, 0.28);
    --text: #e8eaef;
    --text-secondary: #9ca3af;
    --text-tertiary: #6b7280;
    --bg: #12141c;
    --bg-alt: #161822;
    --bg-muted: #161822;
    --bg-dark: #0a0b10;
    --border: rgba(255, 255, 255, 0.08);
    --surface: rgba(28, 30, 38, 0.92);
    --surface-elevated: #1c1e26;
    --header-bg: rgba(18, 20, 28, 0.88);
    --header-border: rgba(255, 255, 255, 0.08);
    --mobile-bar-bg: rgba(18, 20, 28, 0.96);
    --overlay-panel-bg: #1c1e26;
    --device-screen-bg: #1a1f2e;
    --toggle-bar: #e8eaef;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.35);
    --shadow-md: 0 12px 40px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 24px 64px rgba(0, 0, 0, 0.5);
  }
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

svg {
  display: block;
  flex-shrink: 0;
}

/* 固定尺寸图标，避免被 max-width:100% 或 flex 撑大 */
.brand-mark img,
.qr-box img {
  width: 100%;
  height: 100%;
  max-width: none;
  object-fit: cover;
}

.container {
  width: min(100% - 48px, var(--max));
  margin: 0 auto;
}

/* ── Top access bar ── */
.top-access {
  position: sticky;
  top: 0;
  z-index: 210;
  background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.top-access-inner {
  display: flex;
  align-items: center;
  gap: 16px;
  min-height: 52px;
  padding: 8px 0;
}

.top-access-label {
  flex-shrink: 0;
  font-size: 0.75rem;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.5);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.top-access-links {
  display: flex;
  flex: 1;
  gap: 10px;
  justify-content: flex-end;
}

.access-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 8px 16px;
  border-radius: 12px;
  font-size: 0.875rem;
  font-weight: 600;
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.12);
  background: rgba(255, 255, 255, 0.06);
  transition: background 0.2s, border-color 0.2s, transform 0.15s;
}

.access-btn:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.22);
  transform: translateY(-1px);
}

.access-btn svg {
  width: 18px;
  height: 18px;
  max-width: 18px;
  max-height: 18px;
}

.access-btn span {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
  text-align: left;
}

.access-btn small {
  font-size: 0.625rem;
  font-weight: 500;
  opacity: 0.65;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.access-btn strong {
  font-size: 0.8125rem;
}

.access-web:hover { border-color: rgba(79, 110, 247, 0.5); background: rgba(79, 110, 247, 0.15); }
.access-h5:hover { border-color: rgba(168, 85, 247, 0.5); background: rgba(168, 85, 247, 0.15); }
.access-android:hover { border-color: rgba(34, 197, 94, 0.5); background: rgba(34, 197, 94, 0.15); }

.nav-overlay-access {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin-bottom: 20px;
}

.nav-overlay-access .access-btn {
  flex-direction: column;
  justify-content: center;
  padding: 14px 8px;
  font-size: 0.875rem;
  font-weight: 600;
  text-align: center;
  gap: 6px;
  min-height: 52px;
}

.nav-overlay-access .access-btn span {
  align-items: center;
}

/* ── Header ── */
.site-header {
  position: sticky;
  top: 52px;
  z-index: 200;
  background: var(--header-bg);
  backdrop-filter: blur(20px) saturate(1.4);
  border-bottom: 1px solid var(--header-border);
}

.header-inner {
  display: flex;
  align-items: center;
  gap: 24px;
  min-height: 64px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.0625rem;
  flex-shrink: 0;
}

.brand-mark {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  min-width: 36px;
  min-height: 36px;
  border-radius: 10px;
  overflow: hidden;
  flex-shrink: 0;
  box-shadow: 0 4px 12px var(--primary-glow);
}

.brand-mark img {
  width: 100%;
  height: 100%;
  min-width: 0;
  object-fit: cover;
}

.brand-mark.sm {
  width: 32px;
  height: 32px;
  min-width: 32px;
  min-height: 32px;
}

.nav-desktop {
  display: flex;
  gap: 32px;
  margin-left: 16px;
}

.nav-desktop a {
  color: var(--text-secondary);
  font-size: 0.9375rem;
  font-weight: 500;
  transition: color 0.2s;
}

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

.nav-desktop a.active {
  font-weight: 600;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-left: auto;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  margin-left: auto;
  padding: 0;
  border: none;
  background: transparent;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  margin: 0 auto;
  background: var(--text);
  border-radius: 2px;
}

/* Mobile nav */
.nav-overlay {
  position: fixed;
  inset: 0;
  z-index: 300;
  pointer-events: none;
  visibility: hidden;
}

.nav-overlay.open {
  pointer-events: auto;
  visibility: visible;
}

.nav-overlay-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(11, 17, 32, 0.5);
  opacity: 0;
  transition: opacity 0.25s;
}

.nav-overlay.open .nav-overlay-backdrop {
  opacity: 1;
}

.nav-overlay-panel {
  position: absolute;
  top: 0;
  right: 0;
  width: min(88vw, 320px);
  height: 100%;
  background: var(--overlay-panel-bg);
  padding: 20px 20px calc(24px + env(safe-area-inset-bottom));
  display: flex;
  flex-direction: column;
  transform: translateX(100%);
  transition: transform 0.28s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: -8px 0 32px rgba(0, 0, 0, 0.1);
}

.nav-overlay.open .nav-overlay-panel {
  transform: translateX(0);
}

.nav-overlay-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

.nav-overlay-head .brand-text {
  font-weight: 800;
}

.nav-close {
  width: 40px;
  height: 40px;
  border: none;
  border-radius: 10px;
  background: var(--bg-alt);
  font-size: 1.5rem;
  line-height: 1;
  color: var(--text-secondary);
  cursor: pointer;
}

.nav-overlay-links {
  display: flex;
  flex-direction: column;
  gap: 4px;
  flex: 1;
}

.nav-overlay-links a {
  padding: 14px 12px;
  border-radius: 12px;
  font-size: 1.0625rem;
  font-weight: 600;
}

.nav-overlay-links a:active {
  background: var(--primary-light);
  color: var(--primary);
}

.nav-overlay-actions {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 16px;
}

.btn-block {
  width: 100%;
}

body.mobile-nav-open {
  overflow: hidden;
}

body.has-mobile-bar {
  padding-bottom: calc(72px + env(safe-area-inset-bottom));
}

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 22px;
  border-radius: 12px;
  font-size: 0.9375rem;
  font-weight: 600;
  border: 1px solid transparent;
  transition: transform 0.15s, box-shadow 0.2s, background 0.2s;
  cursor: pointer;
  white-space: nowrap;
}

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

.btn-sm {
  padding: 9px 18px;
  font-size: 0.875rem;
}

.btn-lg {
  padding: 14px 28px;
  font-size: 1rem;
  border-radius: 14px;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), #6b84f8);
  color: #fff;
  box-shadow: 0 8px 24px var(--primary-glow);
}

.btn-primary:hover {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary));
}

.btn-secondary {
  background: var(--surface);
  color: var(--text);
  border-color: var(--border);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  border-color: var(--primary);
  background: var(--bg-alt);
}

.btn-ghost {
  color: var(--text-secondary);
  background: transparent;
  padding: 9px 14px;
}

.btn-ghost:hover {
  color: var(--primary);
  transform: none;
}

.btn-white {
  background: var(--surface);
  color: var(--primary);
  box-shadow: var(--shadow-sm);
}

.btn-white:hover {
  box-shadow: var(--shadow-md);
}

.btn-outline-light {
  background: transparent;
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.35);
}

.btn-outline-light:hover {
  background: rgba(255, 255, 255, 0.1);
}

/* ── Page hero (inner pages) ── */
.page-hero {
  padding: 56px 0 48px;
  background: var(--bg-alt);
  border-bottom: 1px solid var(--border);
}

.page-hero h1 {
  margin: 0 0 12px;
  font-size: clamp(1.875rem, 4vw, 2.5rem);
  font-weight: 800;
  letter-spacing: -0.025em;
}

.page-hero p {
  margin: 0;
  max-width: 520px;
  color: var(--text-secondary);
  font-size: 1.0625rem;
}

.page-hero-dark {
  background: linear-gradient(165deg, #0f172a, #1e293b);
  border-bottom: none;
  color: #fff;
}

.page-hero-dark p {
  color: rgba(255, 255, 255, 0.7);
}

.page-hero-dark .section-tag {
  background: rgba(255, 255, 255, 0.1);
  color: rgba(255, 255, 255, 0.9);
}

/* ── Explore cards (home) ── */
.explore-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.explore-card {
  display: flex;
  flex-direction: column;
  padding: 32px 28px;
  border-radius: var(--radius-lg);
  background: var(--surface);
  border: 1px solid var(--border);
  transition: box-shadow 0.25s, transform 0.25s, border-color 0.25s;
}

.explore-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-4px);
  border-color: rgba(79, 110, 247, 0.25);
}

.explore-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  margin-bottom: 16px;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 700;
  line-height: 1;
}

.explore-icon.blue { background: #eef1ff; color: var(--primary); }
.explore-icon.green { background: #ecfdf5; color: #16a34a; }
.explore-icon.purple { background: #f5f3ff; color: #7c3aed; }

.explore-card h3 {
  margin: 0 0 10px;
  font-size: 1.25rem;
}

.explore-card p {
  margin: 0;
  flex: 1;
  color: var(--text-secondary);
  font-size: 0.9375rem;
  line-height: 1.65;
}

.explore-link {
  margin-top: 20px;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--primary);
}

.highlights-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.highlight-pill {
  padding: 24px 28px;
  border-radius: var(--radius);
  background: var(--surface);
  border: 1px solid var(--border);
  text-align: center;
}

.highlight-pill strong {
  display: block;
  margin-bottom: 6px;
  font-size: 1.0625rem;
}

.highlight-pill span {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.hero-home {
  padding-bottom: 72px;
}

/* ── Feature detail ── */
.feature-detail-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-detail {
  padding: 28px;
  border-radius: var(--radius);
  background: var(--surface);
  border: 1px solid var(--border);
}

.feature-detail h3 {
  margin: 0 0 14px;
  font-size: 1.0625rem;
}

.feature-detail ul {
  margin: 0;
  padding-left: 1.2em;
}

.feature-detail li {
  margin-bottom: 8px;
  color: var(--text-secondary);
  font-size: 0.9375rem;
  line-height: 1.6;
}

/* ── FAQ ── */
.faq-list {
  max-width: 720px;
  margin: 0 auto;
}

.faq-item {
  margin-bottom: 12px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--surface);
  overflow: hidden;
}

.faq-item summary {
  padding: 18px 22px;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item p {
  margin: 0;
  padding: 0 22px 18px;
  color: var(--text-secondary);
  font-size: 0.9375rem;
  line-height: 1.7;
}

/* ── CTA inline ── */
.cta-inline {
  padding: 40px 0 56px;
  background: var(--bg-alt);
  border-top: 1px solid var(--border);
}

.cta-inline-inner {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  flex-wrap: wrap;
}

.cta-inline-inner p {
  margin: 0;
  font-size: 1.0625rem;
  font-weight: 600;
}

/* ── Download page ── */
.page-download .site-footer {
  margin-top: 0;
}

.download-page-body {
  padding-top: 48px;
  padding-bottom: 64px;
  background: var(--bg-alt);
}

.platform-grid-page {
  margin-bottom: 32px;
}

.platform-card-page {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text);
}

.platform-card-page.featured {
  background: linear-gradient(160deg, #fff 0%, #f0f4ff 100%);
  border-color: rgba(79, 110, 247, 0.3);
  box-shadow: var(--shadow-md);
}

.platform-card-page .platform-body p {
  color: var(--text-secondary);
}

.platform-badge {
  display: inline-block;
  margin-bottom: 8px;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--primary-light);
  color: var(--primary);
  font-size: 0.75rem;
  font-weight: 700;
}

.platform-features {
  margin: 0 0 20px;
  padding-left: 1.2em;
  flex: 1;
}

.platform-features li {
  margin-bottom: 6px;
  color: var(--text-secondary);
  font-size: 0.875rem;
}

.platform-card-page .btn {
  align-self: flex-start;
}

.qr-strip-light {
  background: var(--surface);
  border: 1px solid var(--border);
  margin-bottom: 32px;
}

.qr-text-dark h4 {
  color: var(--text);
}

.qr-text-dark p {
  color: var(--text-secondary);
}

.download-note {
  padding: 28px 32px;
  border-radius: var(--radius-lg);
  background: var(--surface);
  border: 1px solid var(--border);
}

.download-note h4 {
  margin: 0 0 14px;
  font-size: 1rem;
}

.download-note ol {
  margin: 0;
  padding-left: 1.3em;
}

.download-note li {
  margin-bottom: 8px;
  color: var(--text-secondary);
  font-size: 0.9375rem;
  line-height: 1.65;
}

/* Inner page hero (matches home orbs) */
.hero-page {
  padding: 48px 0 44px;
}

.hero-page .hero-content-center {
  position: relative;
  z-index: 1;
  max-width: 640px;
  margin: 0 auto;
  text-align: center;
}

.hero-page h1 {
  margin: 12px 0 14px;
  font-size: clamp(1.75rem, 4vw, 2.35rem);
  font-weight: 800;
  letter-spacing: -0.025em;
}

.hero-page .hero-desc {
  margin: 0 auto;
  max-width: 520px;
  color: var(--text-secondary);
  font-size: 1.0625rem;
  line-height: 1.65;
}

.explore-card-static {
  cursor: default;
  display: flex;
  flex-direction: column;
}

.explore-card-static .btn {
  margin-top: 20px;
  align-self: flex-start;
}

.explore-card-static:hover {
  transform: translateY(-2px);
}

.explore-icon.orange { background: #fff7ed; color: #ea580c; }

/* Legal / guide prose inside landing shell */
.content-prose {
  max-width: 720px;
  margin: 0 auto;
}

.content-prose h1 {
  margin: 0 0 16px;
  font-size: clamp(1.5rem, 3vw, 1.875rem);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.content-prose h2 {
  margin: 32px 0 12px;
  font-size: 1.125rem;
  font-weight: 700;
}

.content-prose p,
.content-prose li {
  color: var(--text-secondary);
  font-size: 0.9375rem;
  line-height: 1.7;
}

.content-prose ul,
.content-prose ol {
  margin: 0 0 16px;
  padding-left: 1.35em;
}

.content-prose li { margin-bottom: 8px; }

.content-prose .lead {
  font-size: 1.0625rem;
  color: var(--text);
}

.content-prose .cta-row {
  margin-top: 32px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.steps-list {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: step;
}

.steps-list li {
  position: relative;
  margin-bottom: 16px;
  padding-left: 2.5rem;
  counter-increment: step;
}

.steps-list li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0;
  width: 1.75rem;
  height: 1.75rem;
  border-radius: 50%;
  background: var(--primary-light);
  color: var(--primary);
  font-size: 0.8125rem;
  font-weight: 700;
  line-height: 1.75rem;
  text-align: center;
}

.hero {
  position: relative;
  padding: 72px 0 88px;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.5;
}

.orb-1 {
  width: 480px;
  height: 480px;
  background: rgba(79, 110, 247, 0.25);
  top: -120px;
  right: -80px;
}

.orb-2 {
  width: 360px;
  height: 360px;
  background: rgba(139, 92, 246, 0.18);
  bottom: -60px;
  left: -60px;
}

.orb-3 {
  width: 200px;
  height: 200px;
  background: rgba(79, 110, 247, 0.15);
  top: 40%;
  left: 30%;
}

.grid-pattern {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(79, 110, 247, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(79, 110, 247, 0.04) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black, transparent);
}

.hero-layout {
  position: relative;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 20px;
  padding: 6px 14px 6px 10px;
  border-radius: 999px;
  background: var(--primary-light);
  color: var(--primary);
  font-size: 0.8125rem;
  font-weight: 600;
  border: 1px solid rgba(79, 110, 247, 0.15);
}

.badge-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--primary);
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.6; transform: scale(0.85); }
}

.hero h1 {
  margin: 0 0 20px;
  font-size: clamp(2.5rem, 5vw, 3.75rem);
  line-height: 1.1;
  letter-spacing: -0.035em;
  font-weight: 800;
}

.gradient-text {
  background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  margin: 0 0 32px;
  max-width: 460px;
  color: var(--text-secondary);
  font-size: 1.0625rem;
  line-height: 1.75;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 40px;
}

.hero-stats {
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 20px 24px;
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--border);
  backdrop-filter: blur(8px);
  box-shadow: var(--shadow-sm);
}

.stat strong {
  display: block;
  font-size: 1rem;
  color: var(--text);
  margin-bottom: 2px;
}

.stat span {
  font-size: 0.8125rem;
  color: var(--text-tertiary);
}

.stat-divider {
  width: 1px;
  height: 32px;
  background: var(--border);
}

/* Hero device mockup */
.hero-visual {
  position: relative;
  display: flex;
  justify-content: center;
  padding: 20px 0;
}

.device-frame {
  position: relative;
  width: min(260px, 85vw);
  max-width: 260px;
  margin: 0 auto;
  padding: 10px;
  border-radius: 32px;
  background: linear-gradient(145deg, #1e293b, #0f172a);
  box-shadow: var(--shadow-lg);
  z-index: 2;
}

.device-notch {
  position: absolute;
  top: 18px;
  left: 50%;
  transform: translateX(-50%);
  width: 80px;
  height: 24px;
  background: #0f172a;
  border-radius: 0 0 14px 14px;
  z-index: 3;
}

.device-screen {
  border-radius: 24px;
  background: var(--device-screen-bg);
  overflow: hidden;
  min-height: 320px;
  display: flex;
  flex-direction: column;
}

.app-header {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 44px 16px 14px;
  background: var(--surface);
  font-weight: 700;
  font-size: 0.9375rem;
  border-bottom: 1px solid #e2e8f0;
  position: relative;
}

.app-back {
  position: absolute;
  left: 16px;
  width: 8px;
  height: 8px;
  border-left: 2px solid #94a3b8;
  border-bottom: 2px solid #94a3b8;
  transform: rotate(45deg);
}

.app-online {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #22c55e;
}

.app-messages {
  flex: 1;
  padding: 16px 14px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.bubble {
  max-width: 78%;
  padding: 10px 14px;
  border-radius: 16px;
  font-size: 0.8125rem;
  line-height: 1.45;
}

.bubble.in {
  align-self: flex-start;
  background: var(--surface);
  color: var(--text);
  border-bottom-left-radius: 4px;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
}

.bubble.out {
  align-self: flex-end;
  background: var(--primary);
  color: #fff;
  border-bottom-right-radius: 4px;
}

.bubble.media {
  display: flex;
  align-items: center;
  gap: 6px;
  background: var(--surface);
  color: var(--text);
  border: 1px solid #e2e8f0;
}

.app-input {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 14px;
  background: var(--surface);
  border-top: 1px solid #e2e8f0;
}

.app-input span:first-child {
  flex: 1;
  padding: 8px 14px;
  border-radius: 20px;
  background: var(--device-screen-bg);
  color: var(--text-tertiary);
  font-size: 0.75rem;
}

.app-send {
  margin-left: 10px;
  color: var(--primary);
  font-size: 0.75rem;
  font-weight: 600;
}

.float-card {
  position: absolute;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  border-radius: 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-md);
  animation: float 4s ease-in-out infinite;
  z-index: 3;
}

.float-card.card-1 {
  top: 8%;
  left: -8%;
  animation-delay: 0s;
}

.float-card.card-2 {
  bottom: 12%;
  right: -6%;
  animation-delay: 1.5s;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

.float-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 10px;
  font-size: 0.875rem;
}

.float-icon.green {
  background: #ecfdf5;
  color: #16a34a;
}

.float-icon.blue {
  background: var(--primary-light);
  color: var(--primary);
}

.float-card strong {
  display: block;
  font-size: 0.8125rem;
}

.float-card span {
  font-size: 0.75rem;
  color: var(--text-tertiary);
}

/* ── Sections ── */
.section {
  padding: 96px 0;
}

.section-alt {
  background: var(--bg-alt);
}

.section-head {
  text-align: center;
  max-width: 520px;
  margin: 0 auto 56px;
}

.section-head.light h2,
.section-head.light p {
  color: #fff;
}

.section-head.light p {
  opacity: 0.8;
}

.section-tag {
  display: inline-block;
  margin-bottom: 12px;
  padding: 4px 12px;
  border-radius: 999px;
  background: var(--primary-light);
  color: var(--primary);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.section-head.light .section-tag {
  background: rgba(255, 255, 255, 0.12);
  color: rgba(255, 255, 255, 0.9);
}

.section-head h2 {
  margin: 0 0 12px;
  font-size: clamp(1.75rem, 3vw, 2.375rem);
  letter-spacing: -0.025em;
  font-weight: 800;
}

.section-head p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 1.0625rem;
}

/* ── Bento grid ── */
.bento-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: auto auto;
  gap: 20px;
}

.bento-card {
  padding: 28px;
  border-radius: var(--radius-lg);
  background: var(--surface);
  border: 1px solid var(--border);
  transition: box-shadow 0.25s, transform 0.25s;
}

.bento-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.bento-large {
  grid-row: span 2;
}

.bento-wide {
  grid-column: span 2;
}

.bento-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  margin-bottom: 14px;
  border-radius: 11px;
  flex-shrink: 0;
}

.bento-icon svg {
  width: 20px;
  height: 20px;
  max-width: 20px;
  max-height: 20px;
}

.bento-icon.blue { background: #eef1ff; color: var(--primary); }
.bento-icon.green { background: #ecfdf5; color: #16a34a; }
.bento-icon.purple { background: #f5f3ff; color: #7c3aed; }
.bento-icon.orange { background: #fff7ed; color: #ea580c; }
.bento-icon.rose { background: #fff1f2; color: #e11d48; }

.bento-card h3 {
  margin: 0 0 8px;
  font-size: 1.125rem;
}

.bento-card p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.9375rem;
  line-height: 1.65;
}

.bento-preview {
  margin-top: 24px;
  padding: 16px;
  border-radius: 14px;
  background: var(--bg-alt);
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.mini-msg {
  max-width: 80%;
  padding: 8px 12px;
  border-radius: 12px;
  font-size: 0.75rem;
}

.mini-msg.left {
  align-self: flex-start;
  background: var(--surface);
  border-bottom-left-radius: 3px;
}

.mini-msg.right {
  align-self: flex-end;
  background: var(--primary);
  color: #fff;
  border-bottom-right-radius: 3px;
}

/* ── Showcase ── */
.showcase-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.showcase-card {
  padding: 32px 28px;
  border-radius: var(--radius-lg);
  background: var(--surface);
  border: 1px solid var(--border);
  text-align: center;
  transition: box-shadow 0.25s, transform 0.25s;
}

.showcase-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}

.showcase-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  margin-bottom: 14px;
  border-radius: 12px;
  font-size: 1.25rem;
  line-height: 1;
}

.showcase-icon.work { background: #eef1ff; }
.showcase-icon.life { background: #ecfdf5; }
.showcase-icon.team { background: #f5f3ff; }

.showcase-card h3 {
  margin: 0 0 10px;
  font-size: 1.125rem;
}

.showcase-card p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.9375rem;
  line-height: 1.65;
}

/* ── Steps ── */
.steps-flow {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.steps-flow li {
  position: relative;
  padding: 32px 28px;
  border-radius: var(--radius-lg);
  background: var(--bg-alt);
  border: 1px solid var(--border);
}

.steps-flow li:not(:last-child)::after {
  content: "";
  position: absolute;
  top: 50%;
  right: -20px;
  width: 24px;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), transparent);
  transform: translateY(-50%);
}

.step-index {
  display: block;
  margin-bottom: 16px;
  font-size: 2rem;
  font-weight: 800;
  line-height: 1;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  opacity: 0.9;
}

.steps-flow h4 {
  margin: 0 0 8px;
  font-size: 1.125rem;
}

.steps-flow p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.9375rem;
  line-height: 1.65;
}

/* ── Download ── */
.download-section {
  background: linear-gradient(165deg, #0f172a 0%, #1e293b 50%, #0f172a 100%);
  color: #fff;
}

.platform-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 40px;
}

.platform-card {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 28px;
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  transition: background 0.2s, border-color 0.2s;
}

.platform-card:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.18);
}

.platform-card.featured {
  background: rgba(79, 110, 247, 0.15);
  border-color: rgba(79, 110, 247, 0.35);
}

.platform-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  min-width: 44px;
  min-height: 44px;
  border-radius: 12px;
  flex-shrink: 0;
}

.platform-icon svg {
  width: 22px;
  height: 22px;
  max-width: 22px;
  max-height: 22px;
}

.platform-icon.android { background: rgba(34, 197, 94, 0.2); color: #4ade80; }
.platform-icon.web { background: rgba(79, 110, 247, 0.2); color: #93b4ff; }
.platform-icon.mobile { background: rgba(168, 85, 247, 0.2); color: #c084fc; }

.platform-body {
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex: 1;
}

.platform-body h3 {
  margin: 0;
  font-size: 1.125rem;
}

.platform-body p {
  margin: 0;
  flex: 1;
  color: rgba(255, 255, 255, 0.65);
  font-size: 0.9375rem;
  line-height: 1.6;
}

.platform-body .btn {
  margin-top: 8px;
  align-self: flex-start;
}

.qr-strip {
  display: flex;
  align-items: center;
  gap: 28px;
  padding: 24px 32px;
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.qr-box {
  flex-shrink: 0;
  padding: 10px;
  background: var(--surface);
  border-radius: 12px;
}

.qr-box img {
  width: 112px;
  height: 112px;
  max-width: 112px;
  max-height: 112px;
}

.qr-text h4 {
  margin: 0 0 6px;
  font-size: 1.0625rem;
}

.qr-text p {
  margin: 0;
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.9375rem;
  line-height: 1.6;
  max-width: 400px;
}

/* ── CTA ── */
.cta-banner {
  padding: 64px 0;
  background: linear-gradient(135deg, var(--primary), #6b84f8 50%, var(--accent));
}

.cta-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}

.cta-copy h2 {
  margin: 0 0 6px;
  font-size: 1.75rem;
  color: #fff;
  font-weight: 800;
}

.cta-copy p {
  margin: 0;
  color: rgba(255, 255, 255, 0.9);
}

/* ── Footer ── */
.site-footer {
  padding: 56px 0 0;
  background: var(--bg-dark);
  color: rgba(255, 255, 255, 0.65);
}

.footer-top {
  display: grid;
  grid-template-columns: 1.2fr 2fr;
  gap: 48px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-brand .brand {
  margin-bottom: 14px;
}

.footer-brand p {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.65;
  max-width: 300px;
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.footer-col h5 {
  margin: 0 0 14px;
  color: #fff;
  font-size: 0.875rem;
  font-weight: 700;
}

.footer-col a {
  display: block;
  margin-bottom: 10px;
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.5);
  transition: color 0.2s;
}

.footer-col a:hover {
  color: #fff;
}

.footer-bottom {
  padding: 20px 0 28px;
}

.footer-bottom p {
  margin: 0;
  font-size: 0.8125rem;
  color: rgba(255, 255, 255, 0.35);
}

/* ── Mobile bar ── */
.mobile-bar {
  display: none;
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 150;
  padding: 10px 16px calc(10px + env(safe-area-inset-bottom));
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(16px);
  border-top: 1px solid var(--border);
  gap: 10px;
  box-shadow: 0 -4px 24px rgba(0, 0, 0, 0.06);
}

.mobile-bar-btn {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  border-radius: 14px;
  font-size: 1rem;
  font-weight: 700;
  border: 1px solid transparent;
}

.mobile-bar-btn.primary {
  flex: 1.4;
  background: var(--primary);
  color: #fff;
  box-shadow: 0 6px 20px var(--primary-glow);
}

.mobile-bar-btn.secondary {
  background: var(--surface);
  color: var(--text);
  border-color: var(--border);
}

/* ── Responsive ── */
@media (max-width: 1024px) {
  .hero-layout {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 48px;
  }

  .hero-desc {
    margin-left: auto;
    margin-right: auto;
  }

  .hero-cta {
    justify-content: center;
  }

  .hero-stats {
    justify-content: center;
  }

  .float-card.card-1 {
    left: 0;
  }

  .float-card.card-2 {
    right: 0;
  }

  .bento-grid {
    grid-template-columns: 1fr 1fr;
  }

  .bento-large {
    grid-row: span 1;
    grid-column: span 2;
  }

  .bento-wide {
    grid-column: span 2;
  }

  .showcase-row,
  .platform-grid,
  .steps-flow {
    grid-template-columns: 1fr;
  }

  .steps-flow li:not(:last-child)::after {
    display: none;
  }

  .footer-top {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .container {
    width: min(100% - 32px, var(--max));
  }

  .top-access-inner {
    min-height: 56px;
    padding: 10px 0;
    gap: 8px;
  }

  .top-access-label {
    display: none;
  }

  .top-access-links {
    width: 100%;
    gap: 8px;
  }

  .access-btn {
    flex: 1;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 10px 6px;
    gap: 5px;
    min-height: 52px;
    border-radius: 10px;
  }

  .access-btn small {
    display: none;
  }

  .access-btn span {
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
  }

  .access-btn strong {
    font-size: 0.8125rem;
    line-height: 1.25;
    white-space: nowrap;
  }

  .access-btn svg {
    width: 20px;
    height: 20px;
    max-width: 20px;
    max-height: 20px;
  }

  .site-header {
    top: 56px;
  }

  .explore-grid,
  .highlights-row,
  .feature-detail-grid {
    grid-template-columns: 1fr;
  }

  .explore-card:hover {
    transform: none;
  }

  .page-hero {
    padding: 40px 0 32px;
  }

  .platform-card-page .btn {
    width: 100%;
    align-self: stretch;
  }

  .qr-strip {
    flex-direction: column;
    text-align: center;
  }

  .nav-desktop,
  .header-actions-desktop,
  .cta-banner-desktop,
  .qr-panel-desktop {
    display: none !important;
  }

  .nav-toggle,
  .mobile-bar {
    display: flex;
  }

  .hero {
    padding: 40px 0 56px;
  }

  .hero-layout {
    text-align: left;
  }

  .hero h1 br {
    display: none;
  }

  .hero-desc {
    margin-left: 0;
    font-size: 0.9375rem;
  }

  .hero-cta {
    flex-direction: column;
    justify-content: stretch;
  }

  .hero-cta .btn {
    width: 100%;
  }

  .hero-stats {
    flex-wrap: wrap;
    gap: 16px;
    justify-content: flex-start;
  }

  .stat-divider {
    display: none;
  }

  .stat {
    flex: 1 1 28%;
    min-width: 80px;
  }

  .hero-visual {
    padding: 0;
  }

  .device-frame {
    width: 240px;
  }

  .device-screen {
    min-height: 400px;
  }

  .float-card {
    display: none;
  }

  .section {
    padding: 56px 0;
  }

  .section-head {
    text-align: left;
    margin-bottom: 32px;
  }

  .bento-grid {
    grid-template-columns: 1fr;
  }

  .bento-large,
  .bento-wide {
    grid-column: span 1;
  }

  .bento-card:hover {
    transform: none;
  }

  .showcase-card:hover {
    transform: none;
  }

  .download-card-desktop-only {
    display: none;
  }

  .platform-body .btn {
    width: 100%;
    align-self: stretch;
  }

  .footer-cols {
    grid-template-columns: 1fr 1fr;
    gap: 24px;
  }

  .footer-brand {
    grid-column: 1 / -1;
  }

  .footer-brand p {
    max-width: none;
  }
}

@media (max-width: 420px) {
  .access-btn strong {
    font-size: 0.75rem;
    white-space: normal;
    line-height: 1.2;
  }
}

@media (max-width: 480px) {
  .container {
    width: min(100% - 24px, var(--max));
  }

  .hero h1 {
    font-size: 2rem;
  }

  .device-frame {
    width: 220px;
  }

  .footer-cols {
    grid-template-columns: 1fr;
  }
}

@media (min-width: 769px) {
  .nav-toggle,
  .mobile-bar,
  .nav-overlay {
    display: none !important;
  }

  .download-card-android {
    order: -1;
  }
}

/* ── Dark mode (跟随系统) ── */
@media (prefers-color-scheme: dark) {
  .btn-white,
  .btn-secondary,
  .explore-card,
  .explore-card-static,
  .platform-card,
  .platform-card-page,
  .bento-card,
  .download-card,
  .feature-card,
  .guide-step,
  .stat-card,
  .faq-item,
  .pricing-card,
  .mock-window,
  .chat-bubble,
  .device-msg,
  .float-card,
  .qr-box,
  .content-card {
    background: var(--surface) !important;
    border-color: var(--border);
    color: var(--text);
  }

  .device-screen,
  .device-msg.recv,
  .mock-body,
  .chat-panel {
    background: var(--device-screen-bg) !important;
  }

  .mobile-bar {
    background: var(--mobile-bar-bg) !important;
    border-top-color: var(--border) !important;
  }

  .mobile-bar-btn.secondary {
    background: var(--surface);
    border-color: var(--border);
    color: var(--text);
  }

  .nav-toggle span {
    background: var(--toggle-bar);
  }

  .explore-icon.blue,
  .bento-icon.blue {
    background: rgba(79, 110, 247, 0.18);
    color: #8da0ff;
  }

  .explore-icon.green,
  .bento-icon.green {
    background: rgba(22, 163, 74, 0.18);
    color: #4ade80;
  }

  .explore-icon.purple,
  .bento-icon.purple {
    background: rgba(124, 58, 237, 0.2);
    color: #c4b5fd;
  }

  .explore-icon.orange,
  .bento-icon.orange {
    background: rgba(234, 88, 12, 0.18);
    color: #fb923c;
  }

  .bento-icon.rose {
    background: rgba(225, 29, 72, 0.18);
    color: #fb7185;
  }

  .platform-card-page.featured,
  .platform-card.featured {
    background: linear-gradient(160deg, #1c1e26 0%, #1a2035 100%) !important;
  }

  .page-hero:not(.page-hero-dark) {
    background: var(--bg);
  }

  .section-alt,
  .section-muted {
    background: var(--bg-alt);
  }

  .content-prose code,
  .content-prose pre {
    background: var(--bg-alt);
    border-color: var(--border);
  }

  .hero-orb,
  .hero-grid {
    opacity: 0.35;
  }

  input,
  textarea,
  select {
    background: var(--surface-elevated);
    color: var(--text);
    border-color: var(--border);
  }
}