/* ========================================
   Binance Chinese Website - Global Styles
   Bing SEO Optimized
   ======================================== */

/* --- CSS Variables --- */
:root {
  --bg-primary: #0B0E11;
  --bg-secondary: #1E2329;
  --bg-tertiary: #2B3139;
  --brand-gold: #F0B90B;
  --brand-gold-light: #FCD535;
  --brand-gold-dark: #C99A06;
  --text-primary: #EAECEF;
  --text-secondary: #848E9C;
  --text-muted: #5E6673;
  --success: #0ECB81;
  --danger: #F6465D;
  --border-color: #2B3139;
  --shadow-gold: 0 0 20px rgba(240, 185, 11, 0.15);
  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.3);
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --max-width: 1200px;
  --nav-height: 72px;
  --transition: all 0.3s ease;
}

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

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

body {
  font-family: var(--font-family);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: var(--brand-gold);
  text-decoration: none;
  transition: var(--transition);
}

a:hover {
  color: var(--brand-gold-light);
}

ul, ol {
  list-style: none;
}

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

table {
  width: 100%;
  border-collapse: collapse;
}

/* --- Utility Classes --- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 100px 0;
}

.section-title {
  font-size: 2.5rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 16px;
  background: linear-gradient(135deg, var(--brand-gold), var(--brand-gold-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-subtitle {
  font-size: 1.125rem;
  color: var(--text-secondary);
  text-align: center;
  max-width: 600px;
  margin: 0 auto 60px;
}

.text-gold {
  color: var(--brand-gold);
}

.text-green {
  color: var(--success);
}

.text-red {
  color: var(--danger);
}

.text-center {
  text-align: center;
}

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

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: var(--transition);
  gap: 8px;
  text-decoration: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--brand-gold), var(--brand-gold-light));
  color: #0B0E11;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-gold);
  color: #0B0E11;
}

.btn-outline {
  background: transparent;
  color: var(--brand-gold);
  border: 1px solid var(--brand-gold);
}

.btn-outline:hover {
  background: rgba(240, 185, 11, 0.1);
  transform: translateY(-2px);
  color: var(--brand-gold);
}

.btn-sm {
  padding: 10px 24px;
  font-size: 0.875rem;
}

.btn-lg {
  padding: 18px 40px;
  font-size: 1.125rem;
}

/* --- Navigation --- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  z-index: 1000;
  transition: var(--transition);
  background: rgba(11, 14, 17, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid transparent;
}

.navbar.scrolled {
  background: rgba(11, 14, 17, 0.98);
  border-bottom-color: var(--border-color);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
}

.nav-logo svg {
  width: 32px;
  height: 32px;
}

.nav-logo span {
  background: linear-gradient(135deg, var(--brand-gold), var(--brand-gold-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-menu a {
  color: var(--text-secondary);
  font-size: 0.9375rem;
  font-weight: 500;
  position: relative;
  padding: 4px 0;
}

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

.nav-menu a.active::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--brand-gold);
  border-radius: 1px;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 4px;
  background: none;
  border: none;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 1px;
  transition: var(--transition);
}

/* --- Cards --- */
.card {
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  padding: 32px;
  transition: var(--transition);
}

.card:hover {
  border-color: rgba(240, 185, 11, 0.3);
  transform: translateY(-4px);
  box-shadow: var(--shadow-card);
}

.card-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  background: rgba(240, 185, 11, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  font-size: 1.5rem;
}

.card-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.card-desc {
  color: var(--text-secondary);
  font-size: 0.9375rem;
  line-height: 1.7;
}

/* --- Grid System --- */
.grid {
  display: grid;
  gap: 24px;
}

.grid-2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid-3 {
  grid-template-columns: repeat(3, 1fr);
}

.grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

/* --- Hero Section --- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  padding-top: var(--nav-height);
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 800px;
  height: 800px;
  background: radial-gradient(circle, rgba(240, 185, 11, 0.08) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(240, 185, 11, 0.05) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 700px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 20px;
  background: rgba(240, 185, 11, 0.1);
  border: 1px solid rgba(240, 185, 11, 0.2);
  border-radius: 50px;
  font-size: 0.875rem;
  color: var(--brand-gold);
  margin-bottom: 24px;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 20px;
}

.hero-title .highlight {
  background: linear-gradient(135deg, var(--brand-gold), var(--brand-gold-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: 40px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

/* --- Stats --- */
.stats-section {
  padding: 80px 0;
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  text-align: center;
}

.stat-item .stat-number {
  font-size: 2.5rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--brand-gold), var(--brand-gold-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 8px;
}

.stat-item .stat-label {
  color: var(--text-secondary);
  font-size: 0.9375rem;
}

/* --- Tables --- */
.table-wrapper {
  overflow-x: auto;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
}

.data-table thead {
  background: var(--bg-tertiary);
}

.data-table th {
  padding: 16px 24px;
  text-align: left;
  font-weight: 600;
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  white-space: nowrap;
}

.data-table td {
  padding: 16px 24px;
  border-top: 1px solid var(--border-color);
  font-size: 0.9375rem;
  white-space: nowrap;
}

.data-table tbody tr:hover {
  background: rgba(240, 185, 11, 0.03);
}

/* --- Tabs --- */
.tabs {
  display: flex;
  gap: 4px;
  background: var(--bg-secondary);
  padding: 4px;
  border-radius: var(--radius-md);
  margin-bottom: 40px;
  overflow-x: auto;
}

.tab-btn {
  padding: 12px 24px;
  background: transparent;
  color: var(--text-secondary);
  border: none;
  border-radius: var(--radius-sm);
  font-size: 0.9375rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
}

.tab-btn:hover {
  color: var(--text-primary);
}

.tab-btn.active {
  background: var(--brand-gold);
  color: #0B0E11;
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

/* --- Accordion --- */
.accordion {
  max-width: 800px;
  margin: 0 auto;
}

.accordion-item {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
  overflow: hidden;
  transition: var(--transition);
}

.accordion-item:hover {
  border-color: rgba(240, 185, 11, 0.3);
}

.accordion-header {
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  font-weight: 600;
  font-size: 1rem;
  background: none;
  border: none;
  color: var(--text-primary);
  width: 100%;
  text-align: left;
}

.accordion-header .icon {
  font-size: 1.25rem;
  transition: var(--transition);
  color: var(--brand-gold);
  flex-shrink: 0;
  margin-left: 16px;
}

.accordion-item.active .accordion-header .icon {
  transform: rotate(45deg);
}

.accordion-body {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
}

.accordion-body-inner {
  padding: 0 24px 20px;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* --- Steps / Timeline --- */
.steps {
  position: relative;
  max-width: 800px;
  margin: 0 auto;
}

.steps::before {
  content: '';
  position: absolute;
  left: 28px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--border-color);
}

.step-item {
  display: flex;
  gap: 24px;
  margin-bottom: 48px;
  position: relative;
}

.step-number {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--bg-secondary);
  border: 2px solid var(--brand-gold);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--brand-gold);
  flex-shrink: 0;
  position: relative;
  z-index: 1;
}

.step-content {
  padding-top: 8px;
}

.step-content h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.step-content p {
  color: var(--text-secondary);
  line-height: 1.8;
}

/* --- CTA Banner --- */
.cta-banner {
  background: linear-gradient(135deg, rgba(240, 185, 11, 0.1), rgba(240, 185, 11, 0.02));
  border: 1px solid rgba(240, 185, 11, 0.2);
  border-radius: var(--radius-lg);
  padding: 60px;
  text-align: center;
}

.cta-banner h2 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.cta-banner p {
  color: var(--text-secondary);
  margin-bottom: 32px;
  font-size: 1.125rem;
}

/* --- Footer --- */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 80px 0 32px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 60px;
}

.footer-brand .nav-logo {
  margin-bottom: 16px;
}

.footer-brand p {
  color: var(--text-secondary);
  font-size: 0.875rem;
  line-height: 1.8;
  max-width: 300px;
}

.footer-col h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.footer-col a {
  display: block;
  color: var(--text-secondary);
  font-size: 0.875rem;
  padding: 6px 0;
  transition: var(--transition);
}

.footer-col a:hover {
  color: var(--brand-gold);
  transform: translateX(4px);
}

.footer-bottom {
  padding-top: 32px;
  border-top: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-bottom p {
  color: var(--text-muted);
  font-size: 0.8125rem;
}

.footer-social {
  display: flex;
  gap: 16px;
}

.footer-social a {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--bg-tertiary);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  transition: var(--transition);
  font-size: 1.125rem;
}

.footer-social a:hover {
  background: var(--brand-gold);
  color: #0B0E11;
}

/* --- Page Header --- */
.page-header {
  padding: 160px 0 80px;
  text-align: center;
  position: relative;
}

.page-header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 400px;
  background: radial-gradient(circle, rgba(240, 185, 11, 0.06) 0%, transparent 70%);
  pointer-events: none;
}

.page-header h1 {
  font-size: 3rem;
  font-weight: 800;
  margin-bottom: 16px;
  position: relative;
}

.page-header p {
  font-size: 1.25rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
  position: relative;
}

/* --- Animations --- */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* --- Search Box --- */
.search-box {
  max-width: 500px;
  margin: 0 auto 40px;
  position: relative;
}

.search-box input {
  width: 100%;
  padding: 16px 24px 16px 52px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 1rem;
  font-family: var(--font-family);
  outline: none;
  transition: var(--transition);
}

.search-box input:focus {
  border-color: var(--brand-gold);
  box-shadow: 0 0 0 3px rgba(240, 185, 11, 0.1);
}

.search-box input::placeholder {
  color: var(--text-muted);
}

.search-box .search-icon {
  position: absolute;
  left: 20px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  font-size: 1.125rem;
}

/* --- Download Cards --- */
.download-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 40px;
  text-align: center;
  transition: var(--transition);
}

.download-card:hover {
  border-color: rgba(240, 185, 11, 0.3);
  transform: translateY(-4px);
  box-shadow: var(--shadow-card);
}

.download-card .platform-icon {
  font-size: 3rem;
  margin-bottom: 20px;
  color: var(--brand-gold);
}

.download-card h3 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.download-card .version {
  color: var(--text-muted);
  font-size: 0.875rem;
  margin-bottom: 24px;
}

/* --- Feature List --- */
.feature-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.feature-list li {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--text-secondary);
  font-size: 0.9375rem;
}

.feature-list li::before {
  content: '✓';
  color: var(--success);
  font-weight: 700;
  flex-shrink: 0;
}

/* --- QR Code --- */
.qr-section {
  display: flex;
  justify-content: center;
  gap: 40px;
  flex-wrap: wrap;
  margin-top: 60px;
}

.qr-item {
  text-align: center;
}

.qr-item .qr-box {
  width: 180px;
  height: 180px;
  background: #fff;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
  font-size: 0.875rem;
  color: var(--text-muted);
}

.qr-item p {
  font-weight: 500;
  font-size: 0.9375rem;
}

/* --- Responsive --- */
@media (max-width: 1024px) {
  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
  }
  .footer-grid {
    grid-template-columns: repeat(3, 1fr);
  }
  .hero-title {
    font-size: 2.75rem;
  }
}

@media (max-width: 768px) {
  .section {
    padding: 60px 0;
  }
  .section-title {
    font-size: 2rem;
  }
  .hero-title {
    font-size: 2.25rem;
  }
  .hero-desc {
    font-size: 1.0625rem;
  }
  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
  }
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }
  .stat-item .stat-number {
    font-size: 2rem;
  }
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .nav-menu {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: var(--bg-secondary);
    flex-direction: column;
    padding: 24px;
    gap: 16px;
    border-bottom: 1px solid var(--border-color);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: var(--transition);
  }
  .nav-menu.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }
  .nav-toggle {
    display: flex;
  }
  .nav-actions .btn {
    display: none;
  }
  .page-header h1 {
    font-size: 2.25rem;
  }
  .cta-banner {
    padding: 40px 24px;
  }
  .hero-actions {
    flex-direction: column;
  }
  .hero-actions .btn {
    width: 100%;
  }
  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }
  .hero-title {
    font-size: 1.875rem;
  }
  .section-title {
    font-size: 1.75rem;
  }
  .tabs {
    flex-wrap: nowrap;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }
}