:root {
  --color-primary: #0f172a;
  --color-primary-light: #1e293b;
  --color-primary-dark: #020617;
  --color-accent: #2563eb;
  --color-accent-hover: #1d4ed8;
  --color-accent-soft: rgba(37, 99, 235, 0.12);
  --color-cyan: #0891b2;
  --color-cyan-soft: rgba(8, 145, 178, 0.1);

  --color-white: #ffffff;
  --color-gray-50: #f8fafc;
  --color-gray-100: #f1f5f9;
  --color-gray-200: #e2e8f0;
  --color-gray-300: #cbd5e1;
  --color-gray-400: #94a3b8;
  --color-gray-500: #64748b;
  --color-gray-600: #475569;
  --color-gray-700: #334155;
  --color-gray-800: #1e293b;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;

  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --radius-xl: 20px;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08), 0 2px 4px rgba(0,0,0,0.04);
  --shadow-lg: 0 12px 24px rgba(0,0,0,0.1), 0 4px 8px rgba(0,0,0,0.06);
  --shadow-glow: 0 0 40px rgba(59, 130, 246, 0.15);

  --sidebar-width: 260px;
  --sidebar-collapsed: 72px;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1140px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.65;
  color: var(--color-gray-800);
  background: var(--color-gray-50);
  overflow-x: hidden;
}

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

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

ul { list-style: none; }

.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--sidebar-width);
  height: 100vh;
  background: linear-gradient(180deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
  z-index: 200;
  display: flex;
  flex-direction: column;
  transition: width var(--transition), transform var(--transition);
  box-shadow: 4px 0 24px rgba(0,0,0,0.15);
}

.sidebar-inner {
  flex: 1;
  padding: var(--space-xl) 0;
  overflow-y: auto;
}

.sidebar-logo {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: 0 var(--space-lg) var(--space-xl);
  border-bottom: 1px solid rgba(255,255,255,0.08);
  margin-bottom: var(--space-lg);
  text-decoration: none;
  color: inherit;
}

.logo-icon {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
  filter: brightness(0) invert(1);
}

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

.sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 0 var(--space-md);
}

.nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-md) var(--space-lg);
  color: rgba(255,255,255,0.75);
  font-size: 0.9rem;
  border-radius: var(--radius-md);
  transition: all var(--transition);
}

.nav-link:hover {
  color: var(--color-white);
  background: rgba(255,255,255,0.08);
}

.nav-link.nav-active {
  color: var(--color-white);
  background: var(--color-accent);
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}

.nav-icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  filter: brightness(0) invert(1);
  opacity: 0.95;
}

.nav-link.nav-active .nav-icon {
  filter: brightness(0) invert(1);
}

.main-wrapper {
  margin-left: var(--sidebar-width);
  min-height: 100vh;
  transition: margin-left var(--transition);
}

.mobile-header {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 160;
  height: 56px;
  padding: 0 var(--space-lg);
  background: var(--color-white);
  box-shadow: var(--shadow-sm);
  align-items: center;
  gap: var(--space-md);
}

.menu-btn {
  display: flex;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-sm);
}

.menu-btn span {
  width: 22px;
  height: 2px;
  background: var(--color-gray-700);
  border-radius: 1px;
  transition: var(--transition);
}

.mobile-logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.mobile-logo-icon {
  width: 24px;
  height: 24px;
  flex-shrink: 0;
  filter: invert(42%) sepia(93%) saturate(1200%) hue-rotate(200deg);
}

.mobile-logo-text {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--color-primary);
}

.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.4);
  z-index: 150;
  opacity: 0;
  transition: opacity var(--transition);
}

.sidebar-overlay.is-visible {
  opacity: 1;
}

.section {
  padding: var(--space-3xl) var(--space-xl);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

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

.section-header {
  margin-bottom: var(--space-2xl);
  text-align: center;
}

.section-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto var(--space-md);
  filter: invert(42%) sepia(93%) saturate(1200%) hue-rotate(200deg) brightness(95%);
}

.section-header h2 {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--space-sm);
  letter-spacing: -0.02em;
}

.section-subtitle {
  font-size: 1rem;
  color: var(--color-gray-600);
  max-width: 560px;
  margin: 0 auto;
  line-height: 1.75;
}

.section-overview {
  background: linear-gradient(135deg, #0f172a 0%, #1e3a5f 50%, #0f172a 100%);
  color: var(--color-white);
  padding: var(--space-3xl) var(--space-xl);
  position: relative;
  overflow: hidden;
}

.section-overview::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -20%;
  width: 60%;
  height: 200%;
  background: radial-gradient(ellipse, rgba(59, 130, 246, 0.15) 0%, transparent 70%);
  pointer-events: none;
}

.section-overview .section-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-3xl);
  align-items: center;
  position: relative;
  z-index: 1;
}

.page-title {
  font-size: 2rem;
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: var(--space-lg);
  letter-spacing: -0.03em;
}

.overview-lead { font-size: 1.05rem; opacity: 0.95; margin-bottom: var(--space-md); }
.overview-desc { font-size: 0.95rem; opacity: 0.85; margin-bottom: var(--space-xl); }

.overview-actions { display: flex; gap: var(--space-md); flex-wrap: wrap; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-md) var(--space-xl);
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  font-weight: 600;
  transition: all var(--transition);
  cursor: pointer;
}

.btn-primary {
  background: var(--color-accent);
  color: white;
  border: none;
  box-shadow: 0 4px 14px rgba(59, 130, 246, 0.4);
}

.btn-primary:hover {
  background: var(--color-accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(59, 130, 246, 0.5);
}

.btn-secondary {
  background: transparent;
  color: white;
  border: 2px solid rgba(255,255,255,0.5);
}

.btn-secondary:hover {
  border-color: white;
  background: rgba(255,255,255,0.1);
}

.overview-visual {
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-xl);
}

.overview-img {
  width: 100%;
  min-height: 280px;
  object-fit: cover;
}

.section-download { background: var(--color-white); }

.trust-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  padding: 16px 20px;
  background: #f0fdf4;
  border: 1px solid #bbf7d0;
  border-radius: 12px;
  margin-bottom: 32px;
}

.trust-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
  font-weight: 500;
  color: #166534;
}

.download-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-lg);
}

.download-card {
  padding: var(--space-xl);
  background: var(--color-gray-50);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-gray-200);
  transition: all var(--transition);
}

.download-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-accent);
  background: var(--color-accent-soft);
}

.download-card-icon {
  width: 44px;
  height: 44px;
  margin-bottom: var(--space-md);
  padding: var(--space-sm);
  background: var(--color-accent-soft);
  border-radius: var(--radius-md);
}

.download-card-icon img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  filter: invert(42%) sepia(93%) saturate(1200%) hue-rotate(200deg);
}

.download-card h3 { font-size: 1.05rem; color: var(--color-primary); margin-bottom: var(--space-sm); }
.download-card p { font-size: 0.9rem; color: var(--color-gray-600); line-height: 1.65; }

.section-wallet-type { background: var(--color-gray-50); }

.wallet-type-layout {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: var(--space-2xl);
  align-items: start;
}

.wallet-type-image {
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.type-img { width: 100%; min-height: 300px; object-fit: cover; }

.wallet-type-cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-lg);
}

.type-card {
  padding: var(--space-lg);
  background: var(--color-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-gray-200);
  transition: all var(--transition);
}

.type-card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-md);
}

.type-card h3 { font-size: 1rem; color: var(--color-primary); margin-bottom: var(--space-sm); }
.type-card p { font-size: 0.9rem; color: var(--color-gray-600); line-height: 1.6; }

.section-comparison { background: var(--color-white); }

.comparison-list { display: flex; flex-direction: column; gap: var(--space-xl); }

.comparison-card {
  display: grid;
  grid-template-columns: 300px 1fr;
  gap: var(--space-xl);
  padding: var(--space-xl);
  background: var(--color-gray-50);
  border-radius: var(--radius-xl);
  border: 1px solid var(--color-gray-200);
  transition: all var(--transition);
}

.comparison-card:hover {
  box-shadow: var(--shadow-lg);
  border-color: var(--color-accent);
  background: var(--color-white);
}

.comparison-visual {
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.card-img { width: 100%; min-height: 200px; object-fit: cover; }

.comparison-content h3 { font-size: 1.35rem; color: var(--color-primary); margin-bottom: var(--space-xs); }
.card-en { font-size: 0.85rem; color: var(--color-gray-500); font-weight: 400; }

.card-tag {
  display: inline-block;
  font-size: 0.8rem;
  color: var(--color-accent);
  background: var(--color-accent-soft);
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--radius-full);
  margin-bottom: var(--space-md);
}

.card-meta li {
  font-size: 0.9rem;
  color: var(--color-gray-600);
  line-height: 1.9;
  padding-left: 1em;
  position: relative;
}

.card-meta li::before {
  content: "·";
  position: absolute;
  left: 0;
  color: var(--color-accent);
}

.section-features { background: var(--color-gray-50); }

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-lg);
}

.feature-item {
  padding: var(--space-xl);
  background: var(--color-white);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-gray-200);
  transition: all var(--transition);
}

.feature-item:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-cyan);
  background: var(--color-cyan-soft);
}

.feature-item-wide { grid-column: span 2; }

.feature-icon {
  width: 36px;
  height: 36px;
  margin-bottom: var(--space-md);
  filter: invert(42%) sepia(93%) saturate(1200%) hue-rotate(200deg);
}

.feature-item h4 { font-size: 1rem; color: var(--color-primary); margin-bottom: var(--space-sm); }
.feature-item p { font-size: 0.9rem; color: var(--color-gray-600); line-height: 1.6; }

.section-platform { background: var(--color-white); }

.platform-layout {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: var(--space-2xl);
  align-items: start;
}

.platform-image {
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.platform-img { width: 100%; min-height: 280px; object-fit: cover; }

.platform-list { display: flex; flex-direction: column; gap: var(--space-md); }

.platform-item {
  display: flex;
  gap: var(--space-md);
  padding: var(--space-lg);
  background: var(--color-gray-50);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-gray-200);
  transition: all var(--transition);
}

.platform-item:hover { border-color: var(--color-accent); }

.platform-item-icon {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  filter: invert(42%) sepia(93%) saturate(1200%) hue-rotate(200deg);
}

.platform-item h4 { font-size: 1rem; color: var(--color-primary); margin-bottom: 2px; }
.platform-item p { font-size: 0.9rem; color: var(--color-gray-600); line-height: 1.6; }

.section-security { background: var(--color-gray-50); }

.security-layout {
  display: grid;
  grid-template-columns: 1fr 1.3fr;
  gap: var(--space-2xl);
  align-items: start;
}

.security-image {
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.security-img { width: 100%; min-height: 320px; object-fit: cover; }

.security-list { display: flex; flex-direction: column; gap: var(--space-md); }

.security-item {
  display: flex;
  gap: var(--space-md);
  padding: var(--space-lg);
  background: var(--color-white);
  border-radius: var(--radius-md);
  border-left: 4px solid var(--color-accent);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition);
}

.security-item:hover { box-shadow: var(--shadow-md); }

.security-item-icon {
  width: 24px;
  height: 24px;
  flex-shrink: 0;
  filter: invert(42%) sepia(93%) saturate(1200%) hue-rotate(200deg);
}

.security-item h4 { font-size: 1rem; color: var(--color-primary); margin-bottom: 2px; }
.security-item p { font-size: 0.9rem; color: var(--color-gray-600); line-height: 1.6; }

.section-selection { background: var(--color-white); }

.selection-layout {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: var(--space-2xl);
  align-items: start;
}

.selection-image {
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.selection-img { width: 100%; min-height: 300px; object-fit: cover; }

.selection-cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-lg);
}

.selection-card {
  padding: var(--space-lg);
  background: var(--color-gray-50);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-gray-200);
  transition: all var(--transition);
}

.selection-card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-md);
}

.selection-card-icon {
  width: 28px;
  height: 28px;
  margin-bottom: var(--space-sm);
  filter: invert(42%) sepia(93%) saturate(1200%) hue-rotate(200deg);
}

.selection-card h4 { font-size: 1rem; color: var(--color-primary); margin-bottom: var(--space-sm); }
.selection-card p { font-size: 0.9rem; color: var(--color-gray-600); line-height: 1.6; }

.section-faq { background: var(--color-gray-50); }

.faq-list { max-width: 800px; margin: 0 auto; }

.faq-item {
  border-bottom: 1px solid var(--color-gray-200);
  transition: var(--transition);
}

.faq-item:hover { background: rgba(59, 130, 246, 0.02); }

.faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  padding: var(--space-lg);
  background: none;
  border: none;
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-primary);
  text-align: left;
  cursor: pointer;
  transition: var(--transition);
}

.faq-icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  filter: invert(42%) sepia(93%) saturate(1200%) hue-rotate(200deg);
  transition: transform var(--transition);
}

.faq-item.is-open .faq-icon { transform: rotate(180deg); }

.faq-answer { max-height: 0; overflow: hidden; transition: max-height 0.35s ease; }

.faq-item.is-open .faq-answer { max-height: 800px; }

.no-js .faq-answer { max-height: 2000px; }

.faq-answer p {
  padding: 0 var(--space-lg) var(--space-lg);
  font-size: 0.95rem;
  color: var(--color-gray-600);
  line-height: 1.75;
}

.faq-answer strong { color: var(--color-primary); }

.section-contact {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
  color: var(--color-white);
}

.section-contact .section-icon {
  filter: brightness(0) invert(1);
}
.section-contact .section-header h2 { color: var(--color-white); }

.contact-content {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-xl);
  margin-bottom: var(--space-2xl);
}

.contact-block h3 { font-size: 1rem; margin-bottom: var(--space-sm); opacity: 0.95; }
.contact-block p { font-size: 0.9rem; opacity: 0.9; line-height: 1.7; }

.contact-footer { text-align: center; font-size: 0.9rem; opacity: 0.85; }

.site-footer {
  background: var(--color-primary-dark);
  color: rgba(255, 255, 255, 0.9);
  padding: var(--space-xl) var(--space-lg);
}

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

.footer-inner p {
  font-size: 0.9rem;
  line-height: 1.6;
}

.has-js .section {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.has-js .section.reveal {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 1200px) {
  .download-grid { grid-template-columns: repeat(2, 1fr); }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .feature-item-wide { grid-column: span 1; }
}

@media (max-width: 1024px) {
  .sidebar {
    transform: translateX(-100%);
    width: 280px;
  }

  .sidebar.is-open {
    transform: translateX(0);
  }

  .sidebar-overlay { display: block; }
  .sidebar-overlay.is-visible { display: block; }

  .main-wrapper { margin-left: 0; margin-top: 56px; }

  .mobile-header { display: flex; }

  .section-overview .section-inner { grid-template-columns: 1fr; }
  .overview-visual { order: -1; }

  .wallet-type-layout,
  .platform-layout,
  .security-layout,
  .selection-layout {
    grid-template-columns: 1fr;
  }

  .comparison-card {
    grid-template-columns: 1fr;
  }

  .comparison-visual { max-height: 220px; }
  .card-img { min-height: 200px; }
}

@media (max-width: 768px) {
  .download-grid { grid-template-columns: 1fr; }
  .wallet-type-cards,
  .selection-cards { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: 1fr; }
  .contact-content { grid-template-columns: 1fr; }

  .overview-actions { flex-direction: column; }
  .btn { width: 100%; justify-content: center; }

  .page-title { font-size: 1.5rem !important; }
  .section-header h2 { font-size: 1.4rem; }

  .section { padding: var(--space-2xl) var(--space-lg); }

  .comparison-visual { max-height: 180px; }
  .card-img { min-height: 160px; }

  .overview-img { min-height: 220px; }

  .trust-bar {
    gap: 12px;
    padding: 12px 16px;
  }

  .trust-item {
    font-size: 0.82rem;
  }
}

@media (max-width: 480px) {
  .section { padding: 2rem 1rem; }
  .section-inner { overflow-x: hidden; }

  .page-title { font-size: 1.25rem !important; }
  .section-header h2 { font-size: 1.2rem; }

  .overview-img { min-height: 180px; }
  .comparison-visual { max-height: 140px; }
  .card-img { min-height: 140px; }

  .download-card,
  .type-card,
  .feature-item,
  .platform-item,
  .selection-card,
  .security-item {
    padding: 1rem;
  }

  .btn {
    padding: 0.75rem 1rem;
    font-size: 0.9rem;
  }

  .trust-bar {
    flex-direction: column;
    gap: 8px;
  }

  .trust-item {
    font-size: 0.78rem;
  }
}