/* ===== CSS Variables ===== */
:root {
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-tertiary: #f1f5f9;
  --bg-card: #ffffff;
  --bg-sidebar: #ffffff;
  --bg-code: #f1f5f9;
  --bg-hover: #e2e8f0;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-tertiary: #94a3b8;
  --text-link: #2563eb;
  --border-color: #e2e8f0;
  --border-light: #f1f5f9;
  --accent: #3b82f6;
  --accent-hover: #60a5fa;
  --accent-light: #dbeafe;
  --accent-bg: #eff6ff;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.1);
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --transition: 0.2s ease;
  --sidebar-width: 17%;
  --toc-width: 15%;
  --header-height: 60px;
}

[data-theme="dark"] {
  --bg-primary: #0a0e1a;
  --bg-secondary: #111827;
  --bg-tertiary: #1f2937;
  --bg-card: rgba(31, 41, 55, 0.5);
  --bg-sidebar: #0f172a;
  --bg-code: #1e293b;
  --bg-hover: rgba(59, 130, 246, 0.1);
  --text-primary: #f9fafb;
  --text-secondary: #9ca3af;
  --text-tertiary: #6b7280;
  --text-link: #60a5fa;
  --border-color: rgba(75, 85, 99, 0.3);
  --border-light: rgba(75, 85, 99, 0.15);
  --accent: #3b82f6;
  --accent-hover: #60a5fa;
  --accent-light: rgba(59, 130, 246, 0.15);
  --accent-bg: rgba(59, 130, 246, 0.08);
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.4), 0 2px 4px -2px rgba(0,0,0,0.3);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.4), 0 4px 6px -4px rgba(0,0,0,0.3);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.4), 0 8px 10px -6px rgba(0,0,0,0.3);
  --shadow-glow: 0 0 20px rgba(59, 130, 246, 0.15);
}

/* ===== Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; scroll-padding-top: calc(var(--header-height) + 24px); overflow-x: hidden; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  transition: background var(--transition), color var(--transition);
  position: relative;
  min-height: 100vh;
  overflow-x: hidden;
}

body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: 
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(59, 130, 246, 0.08), transparent),
    radial-gradient(ellipse 60% 40% at 100% 50%, rgba(139, 92, 246, 0.06), transparent),
    radial-gradient(ellipse 50% 30% at 0% 80%, rgba(6, 182, 212, 0.05), transparent);
  pointer-events: none;
  z-index: 0;
  opacity: 0;
  transition: opacity 0.5s ease;
}

[data-theme="dark"] body::before {
  opacity: 1;
}
a { color: var(--text-link); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--accent-hover); text-decoration: underline; }
img { max-width: 100%; height: auto; }
code { background: var(--bg-code); padding: 2px 6px; border-radius: 4px; font-size: 0.9em; }
pre { background: var(--bg-code); padding: 16px; border-radius: var(--radius-md); overflow-x: auto; }
pre code { background: none; padding: 0; }

/* ===== Header ===== */
.site-header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  height: var(--header-height);
  background: rgba(255, 255, 255, 0.85);
  border-bottom: 1px solid var(--border-color);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  transition: all var(--transition);
}
.site-header::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent 0%, #3b82f6 20%, #8b5cf6 50%, #06b6d4 80%, transparent 100%);
  opacity: 0.5;
}
.site-header::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, #3b82f6 0%, #8b5cf6 50%, #06b6d4 100%);
  opacity: 0;
  transition: opacity 0.3s ease;
  box-shadow: 0 0 20px rgba(59, 130, 246, 0.2);
}
.site-header.scrolled::after {
  opacity: 1;
}

[data-theme="dark"] .site-header {
  background: rgba(8, 11, 20, 0.85);
  border-bottom: 1px solid rgba(59, 130, 246, 0.15);
}
[data-theme="dark"] .site-header::before {
  opacity: 0.9;
  box-shadow: 0 0 15px rgba(59, 130, 246, 0.2);
}
[data-theme="dark"] .site-header.scrolled {
  background: rgba(8, 11, 20, 0.95);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.4), 0 0 40px rgba(59, 130, 246, 0.05);
}
.header-inner {
  max-width: 1400px; margin: 0 auto; height: 100%;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 24px;
}
.header-logo {
  display: flex; align-items: center; gap: 10px;
  font-size: 1.15rem; font-weight: 700; color: var(--text-primary);
  text-decoration: none;
  position: relative;
}
.header-logo:hover { text-decoration: none; color: var(--text-primary); }
.header-logo .logo-icon { 
  font-size: 1.5rem; 
  filter: drop-shadow(0 0 8px rgba(59, 130, 246, 0.5));
  transition: all 0.3s ease;
}
.header-logo:hover .logo-icon {
  transform: scale(1.1) rotate(-5deg);
  filter: drop-shadow(0 0 12px rgba(59, 130, 246, 0.7));
}
.header-logo span:last-child {
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--text-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
[data-theme="dark"] .header-logo span:last-child {
  background: linear-gradient(135deg, #ffffff 0%, #60a5fa 40%, #a78bfa 70%, #22d3ee 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  background-size: 200% 200%;
  animation: gradientShift 4s ease infinite;
}
[data-theme="dark"] .header-logo .logo-icon {
  filter: drop-shadow(0 0 10px rgba(59, 130, 246, 0.6));
}
[data-theme="dark"] .header-logo:hover .logo-icon {
  filter: drop-shadow(0 0 16px rgba(59, 130, 246, 0.8));
}
.header-nav { display: flex; align-items: center; gap: 8px; }
.header-nav a {
  padding: 6px 14px; border-radius: var(--radius-sm);
  color: var(--text-secondary); font-size: 0.9rem; font-weight: 500;
  transition: all var(--transition); text-decoration: none;
}
.header-nav a:hover { color: var(--text-primary); background: var(--bg-tertiary); text-decoration: none; }
.header-nav a.active { color: var(--accent); background: var(--accent-light); }
.header-actions { display: flex; align-items: center; gap: 8px; }
.theme-toggle, .lang-toggle {
  width: 36px; height: 36px; border: none; background: var(--bg-tertiary);
  border-radius: var(--radius-sm); cursor: pointer; font-size: 0.85rem;
  font-weight: 600;
  display: flex; align-items: center; justify-content: center;
  transition: all var(--transition); color: var(--text-secondary);
}
.theme-toggle:hover, .lang-toggle:hover { background: var(--bg-hover); color: var(--text-primary); }

/* ===== Search (Modern Style) ===== */
.search-container {
  position: relative; flex: 1; max-width: 600px; margin: 0 24px;
}
.search-input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}
.search-input {
  width: 100%; height: 40px; padding: 0 44px 0 44px;
  border: 1px solid var(--border-color); border-radius: 12px;
  background: var(--bg-secondary); color: var(--text-primary);
  font-size: 0.9rem; outline: none; 
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}
.search-input:focus { 
  border-color: var(--accent); 
  box-shadow: 0 0 0 4px var(--accent-light), 0 4px 16px rgba(0, 0, 0, 0.08);
  background: var(--bg-card);
  transform: translateY(-1px);
}

[data-theme="dark"] .search-input {
  background: rgba(31, 41, 55, 0.85);
  border-color: rgba(75, 85, 99, 0.5);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}
[data-theme="dark"] .search-input:focus {
  border-color: rgba(59, 130, 246, 0.7);
  box-shadow: 0 0 20px rgba(59, 130, 246, 0.2), 0 0 0 3px rgba(59, 130, 246, 0.15);
  background: rgba(31, 41, 55, 0.95);
}
[data-theme="dark"] .search-results {
  background: rgba(31, 41, 55, 0.9);
  border-color: rgba(75, 85, 99, 0.4);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.4), 0 0 40px rgba(59, 130, 246, 0.1);
}
[data-theme="dark"] .search-results-header {
  background: rgba(17, 24, 39, 0.8);
  border-color: rgba(75, 85, 99, 0.3);
}
[data-theme="dark"] .search-result-item:hover,
[data-theme="dark"] .search-result-item.active {
  background: rgba(59, 130, 246, 0.12);
}
.search-icon {
  position: absolute; left: 18px; top: 50%; transform: translateY(-50%);
  color: var(--text-tertiary); font-size: 1.1rem; pointer-events: none;
  transition: all 0.3s ease;
}
.search-container:focus-within .search-icon {
  color: var(--accent);
  transform: translateY(-50%) scale(1.1);
}
.search-shortcut {
  position: absolute; right: 14px; top: 50%; transform: translateY(-50%);
  display: flex; align-items: center; gap: 4px;
  padding: 4px 8px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  font-size: 0.75rem;
  color: var(--text-tertiary);
  pointer-events: none;
  transition: all 0.2s ease;
}
.search-container:focus-within .search-shortcut {
  opacity: 0.5;
}
.search-clear {
  position: absolute; right: 14px; top: 50%; transform: translateY(-50%);
  width: 24px; height: 24px;
  display: none;
  align-items: center; justify-content: center;
  background: var(--bg-tertiary);
  border: none;
  border-radius: 50%;
  color: var(--text-tertiary);
  cursor: pointer;
  font-size: 0.8rem;
  transition: all 0.2s ease;
}
.search-clear:hover {
  background: var(--border-color);
  color: var(--text-primary);
  transform: translateY(-50%) scale(1.1);
}
.search-clear.visible {
  display: flex;
}
/* Search Results - New Design */
.search-results {
  position: absolute; top: calc(100% + 12px); left: -20px; right: -20px;
  background: var(--bg-card); 
  border: 1px solid var(--border-color);
  border-radius: 16px; 
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15), 0 0 40px rgba(59, 130, 246, 0.05);
  max-height: 520px; 
  overflow-y: auto; 
  display: none; 
  z-index: 200;
  overflow-x: hidden;
  animation: searchDropdown 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  backdrop-filter: blur(20px);
}
@keyframes searchDropdown {
  from {
    opacity: 0;
    transform: translateY(-12px) scale(0.98);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}
.search-results.active { display: block; }
.search-results-header {
  padding: 14px 20px;
  font-size: 0.8rem;
  color: var(--text-tertiary);
  border-bottom: 1px solid var(--border-light);
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--bg-secondary);
}
.search-results-count {
  font-weight: 600;
  color: var(--accent);
  padding: 2px 8px;
  background: var(--accent-light);
  border-radius: 999px;
}
.search-results-list {
  padding: 8px;
}
.search-result-item {
  padding: 14px 16px; 
  cursor: pointer; 
  border-radius: 10px;
  margin-bottom: 4px;
  transition: all 0.2s ease;
  position: relative;
  overflow: hidden;
}
.search-result-item::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--accent);
  transform: scaleY(0);
  transition: transform 0.2s ease;
}
.search-result-item:hover,
.search-result-item.active { 
  background: var(--accent-light); 
  transform: translateX(4px);
}
.search-result-item:hover::before,
.search-result-item.active::before {
  transform: scaleY(1);
}
.search-result-item:last-child { margin-bottom: 0; }
.search-result-title { 
  font-weight: 600; 
  font-size: 0.92rem; 
  color: var(--text-primary);
  margin-bottom: 4px;
}
.search-result-path { 
  font-size: 0.78rem; 
  color: var(--text-tertiary); 
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 6px;
}
.search-result-path svg {
  width: 12px;
  height: 12px;
}
.search-result-preview { 
  font-size: 0.82rem; 
  color: var(--text-secondary); 
  margin-top: 8px;
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
  padding-left: 8px;
  border-left: 2px solid var(--accent-light);
}
.search-result-item mark {
  background: linear-gradient(180deg, transparent 60%, var(--accent-light) 60%);
  color: var(--accent);
  padding: 0 2px;
  border-radius: 2px;
  font-weight: 600;
}

/* No Results */
.search-no-results { 
  padding: 48px 24px; 
  text-align: center; 
  color: var(--text-tertiary); 
  font-size: 0.9rem;
}
.search-no-results-icon {
  font-size: 3rem;
  margin-bottom: 16px;
  opacity: 0.5;
}

/* Search Footer */
.search-footer {
  padding: 12px 20px;
  font-size: 0.75rem;
  color: var(--text-tertiary);
  border-top: 1px solid var(--border-light);
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--bg-secondary);
}
.search-footer-hint {
  display: flex;
  gap: 16px;
}
.search-footer-hint span {
  display: flex;
  align-items: center;
  gap: 4px;
}
.search-footer-hint kbd {
  padding: 2px 6px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: 3px;
  font-size: 0.7rem;
  font-family: inherit;
}

/* ===== Mobile Menu ===== */
.mobile-menu-btn {
  display: none; width: 36px; height: 36px; border: none;
  background: var(--bg-tertiary); border-radius: var(--radius-sm);
  cursor: pointer; font-size: 1.2rem; color: var(--text-secondary);
  align-items: center; justify-content: center;
}

/* ===== Homepage ===== */
.hero {
  padding: calc(var(--header-height) + 60px) 24px 60px;
  background: linear-gradient(135deg, var(--accent-bg) 0%, var(--bg-primary) 50%, var(--accent-bg) 100%);
  text-align: center;
}
.hero-inner { max-width: 900px; margin: 0 auto; }
.hero h1 {
  font-size: 2.8rem; font-weight: 800; line-height: 1.2;
  background: linear-gradient(135deg, var(--accent) 0%, #7c3aed 100%);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text; margin-bottom: 16px;
}
.hero .subtitle { font-size: 1.2rem; color: var(--text-secondary); margin-bottom: 32px; }
.hero-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 28px; border-radius: var(--radius-md);
  font-size: 1rem; font-weight: 600; cursor: pointer;
  transition: all var(--transition); border: none; text-decoration: none;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-hover); color: #fff; box-shadow: var(--shadow-lg); }
.btn-outline { background: transparent; color: var(--accent); border: 2px solid var(--accent); }
.btn-outline:hover { background: var(--accent); color: #fff; }
.btn-lg { padding: 14px 36px; font-size: 1.1rem; }
.btn-sm { padding: 8px 18px; font-size: 0.85rem; }

/* ===== Carousel ===== */
.carousel-section { padding: 60px 24px; background: var(--bg-secondary); }
.carousel-section .section-title {
  text-align: center; font-size: 1.8rem; font-weight: 700;
  margin-bottom: 40px; color: var(--text-primary);
}
.carousel-container { max-width: 1000px; margin: 0 auto; position: relative; }
.carousel-track { overflow: hidden; border-radius: var(--radius-xl); }
.carousel-slides {
  display: flex; transition: transform 0.6s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}
.carousel-slide {
  min-width: 100%; padding: 50px 40px;
  display: flex; align-items: center; gap: 30px;
  background: var(--bg-card); border-radius: var(--radius-xl);
  border: 1px solid var(--border-color);
}
.carousel-icon { font-size: 3.5rem; flex-shrink: 0; }
.carousel-content { flex: 1; }
.carousel-content h3 { font-size: 1.5rem; font-weight: 700; margin-bottom: 10px; color: var(--text-primary); }
.carousel-content p { font-size: 1rem; color: var(--text-secondary); line-height: 1.6; }
.carousel-dots {
  display: flex; justify-content: center; gap: 8px; margin-top: 24px;
}
.carousel-dot {
  width: 10px; height: 10px; border-radius: 50%;
  background: var(--border-color); border: none; cursor: pointer;
  transition: all var(--transition);
}
.carousel-dot.active { background: var(--accent); width: 28px; border-radius: 5px; }

/* ===== Features ===== */
.features-section { padding: 60px 24px; }
.features-section .section-title {
  text-align: center; font-size: 1.8rem; font-weight: 700;
  margin-bottom: 40px; color: var(--text-primary);
}
.features-grid {
  max-width: 1100px; margin: 0 auto;
  display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 24px;
}
.feature-card {
  padding: 28px; background: var(--bg-card); border: 1px solid var(--border-color);
  border-radius: var(--radius-lg); transition: all var(--transition);
}
.feature-card:hover { box-shadow: var(--shadow-lg); transform: translateY(-2px); border-color: var(--accent); }
.feature-card .icon { font-size: 2rem; margin-bottom: 12px; }
.feature-card h3 { font-size: 1.1rem; font-weight: 700; margin-bottom: 8px; }
.feature-card p { font-size: 0.9rem; color: var(--text-secondary); }

/* ===== Services ===== */
.services-section { padding: 60px 24px; background: var(--bg-secondary); }
.services-section .section-title {
  text-align: center; font-size: 1.8rem; font-weight: 700;
  margin-bottom: 40px; color: var(--text-primary);
}
.services-list {
  max-width: 800px; margin: 0 auto;
  display: grid; grid-template-columns: repeat(auto-fit, minmax(350px, 1fr)); gap: 12px;
}
.service-chip {
  display: flex; align-items: center; gap: 12px;
  padding: 14px 18px; background: var(--bg-card);
  border-radius: var(--radius-md); border: 1px solid var(--border-color);
  font-size: 0.92rem; transition: all var(--transition);
}
.service-chip:hover { border-color: var(--accent); box-shadow: var(--shadow-sm); }
.service-chip .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--accent); flex-shrink: 0; }

/* ===== Download Section ===== */
.download-section { padding: 60px 24px; }
.download-card {
  max-width: 800px; margin: 0 auto;
  background: linear-gradient(135deg, var(--accent) 0%, #7c3aed 100%);
  border-radius: var(--radius-xl); padding: 48px; text-align: center; color: #fff;
}
.download-card h2 { font-size: 1.8rem; font-weight: 700; margin-bottom: 12px; }
.download-card p { opacity: 0.9; margin-bottom: 24px; font-size: 1rem; }
.download-card .btn { background: #fff; color: var(--accent); }
.download-card .btn:hover { box-shadow: var(--shadow-lg); }
.download-note {
  max-width: 800px; margin: 16px auto 0; text-align: center;
  font-size: 0.85rem; color: var(--warning); background: var(--bg-secondary);
  padding: 12px 20px; border-radius: var(--radius-md); border: 1px solid var(--border-color);
}

/* ===== Purchase Section ===== */
.purchase-section { padding: 60px 24px; background: var(--bg-secondary); }
.purchase-section .section-title {
  text-align: center; font-size: 1.8rem; font-weight: 700;
  margin-bottom: 40px; color: var(--text-primary);
}
.purchase-grid {
  max-width: 900px; margin: 0 auto;
  display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 24px;
}
.purchase-card {
  background: var(--bg-card); border: 1px solid var(--border-color);
  border-radius: var(--radius-lg); padding: 32px; text-align: center;
  transition: all var(--transition);
}
.purchase-card:hover { box-shadow: var(--shadow-lg); transform: translateY(-2px); }
.purchase-card .icon { font-size: 2.5rem; margin-bottom: 16px; }
.purchase-card h3 { font-size: 1.2rem; font-weight: 700; margin-bottom: 8px; }
.purchase-card p { font-size: 0.9rem; color: var(--text-secondary); margin-bottom: 20px; }
.qrcode-hint {
  font-size: 0.85rem; color: var(--text-tertiary);
  margin-top: 16px; padding-top: 16px; border-top: 1px solid var(--border-color);
}

/* ===== Video Section ===== */
.video-section { padding: 60px 24px; }
.video-section .section-title {
  text-align: center; font-size: 1.8rem; font-weight: 700;
  margin-bottom: 40px; color: var(--text-primary);
}
.video-container {
  max-width: 800px; margin: 0 auto;
  border-radius: var(--radius-xl); overflow: hidden;
  background: #000; aspect-ratio: 16/9;
}
.video-container video { width: 100%; height: 100%; object-fit: contain; }

/* ===== Footer ===== */
.site-footer {
  padding: 32px 24px; text-align: center;
  border-top: 1px solid var(--border-color);
  background: var(--bg-secondary); font-size: 0.85rem; color: var(--text-tertiary);
}
.site-footer a { color: var(--text-secondary); }

/* ===== Help Page Layout ===== */
.help-layout {
  display: flex; margin-top: var(--header-height); min-height: calc(100vh - var(--header-height));
}

/* Resizer */
.resizer {
  position: fixed;
  top: var(--header-height);
  width: 6px;
  height: calc(100vh - var(--header-height));
  cursor: col-resize;
  z-index: 60;
  background: transparent;
  transition: background 0.2s ease;
}
.resizer:hover,
.resizer.active {
  background: var(--accent);
}
.resizer::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 2px;
  height: 40px;
  background: var(--border-color);
  border-radius: 2px;
  transition: background 0.2s ease;
}
.resizer:hover::after,
.resizer.active::after {
  background: var(--accent);
}

.sidebar-resizer {
  left: calc(var(--sidebar-width) - 3px);
}

.toc-resizer {
  right: calc(var(--toc-width) - 3px);
  display: none;
}

@media (min-width: 1200px) {
  .toc-resizer {
    display: block;
  }
}

/* Sidebar */
.help-sidebar {
  position: fixed; top: var(--header-height); left: 0;
  width: var(--sidebar-width); height: calc(100vh - var(--header-height));
  overflow-y: auto; background: var(--bg-sidebar);
  border-right: 1px solid var(--border-color);
  padding: 12px 8px; z-index: 50;
  transition: all var(--transition);
  scrollbar-width: thin; scrollbar-color: var(--border-color) transparent;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

[data-theme="dark"] .help-sidebar {
  background: rgba(15, 23, 42, 0.7);
  border-right: 1px solid rgba(75, 85, 99, 0.3);
}
.help-sidebar::-webkit-scrollbar { width: 4px; }
.help-sidebar::-webkit-scrollbar-track { background: transparent; }
.help-sidebar::-webkit-scrollbar-thumb { background: var(--border-color); border-radius: 2px; }
.sidebar-section { margin-bottom: 6px; padding: 0 12px; }
.sidebar-item {
  display: flex;
  align-items: center;
  padding: 8px 14px;
  font-size: 0.88rem;
  color: var(--text-secondary);
  cursor: pointer;
  border: none;
  border-radius: 8px;
  margin: 2px 0;
  transition: all 0.2s ease;
  text-decoration: none;
  line-height: 1.4;
}
.sidebar-item:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  text-decoration: none;
}
.sidebar-item.active {
  color: #fff;
  background: linear-gradient(135deg, var(--accent) 0%, #7c3aed 100%);
  font-weight: 600;
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.3);
}
.sidebar-item.level-1 {
  padding: 10px 14px;
  font-weight: 700;
  font-size: 0.92rem;
  color: var(--text-primary);
  background: var(--bg-secondary);
  border-radius: 10px;
  margin-bottom: 4px;
  margin-top: 8px;
}
.sidebar-item.level-1:hover {
  background: var(--bg-tertiary);
}
.sidebar-item.level-1.active {
  color: #fff;
  background: linear-gradient(135deg, var(--accent) 0%, #7c3aed 100%);
}
.sidebar-item.level-2 {
  padding: 7px 14px 7px 28px;
  font-size: 0.86rem;
  margin: 1px 0;
}
.sidebar-item.level-3 {
  padding: 6px 14px 6px 42px;
  font-size: 0.82rem;
  margin: 1px 0;
  color: var(--text-tertiary);
}
.sidebar-item.level-3:hover {
  color: var(--text-secondary);
}
.sidebar-toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 14px;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-primary);
  cursor: pointer;
  border: none;
  background: var(--bg-secondary);
  width: 100%;
  text-align: left;
  border-radius: 10px;
  margin-bottom: 4px;
  margin-top: 8px;
  transition: all 0.2s ease;
}
.sidebar-toggle:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}
.sidebar-toggle .arrow {
  transition: transform 0.2s ease;
  font-size: 0.7rem;
  opacity: 0.6;
}
.sidebar-toggle.collapsed .arrow { transform: rotate(-90deg); }
.sidebar-children { overflow: hidden; transition: max-height 0.3s ease; }
.sidebar-children.collapsed { max-height: 0 !important; }

/* Main Content */
.help-main {
  flex: 1; margin-left: var(--sidebar-width); min-width: 0;
  display: flex;
}
.help-content {
  flex: 1; padding: 32px 48px; max-width: 900px; min-width: 0;
}

/* Right TOC */
.help-toc {
  position: fixed; top: var(--header-height); right: 0;
  width: var(--toc-width); height: calc(100vh - var(--header-height));
  overflow-y: auto; padding: 20px 16px;
  border-left: 1px solid var(--border-color);
  background: var(--bg-primary);
  scrollbar-width: thin; scrollbar-color: var(--border-color) transparent;
}
.help-toc::-webkit-scrollbar { width: 4px; }
.help-toc::-webkit-scrollbar-track { background: transparent; }
.help-toc::-webkit-scrollbar-thumb { background: var(--border-color); border-radius: 2px; }
.toc-title { font-size: 0.8rem; font-weight: 700; color: var(--text-tertiary); text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 12px; }
.toc-item {
  display: block; padding: 4px 0; font-size: 0.82rem;
  color: var(--text-tertiary); text-decoration: none;
  border-left: 2px solid transparent; padding-left: 10px;
  transition: all var(--transition);
}
.toc-item:hover { color: var(--text-primary); text-decoration: none; }
.toc-item.active { color: var(--accent); border-left-color: var(--accent); }
.toc-item.level-3 { padding-left: 20px; }
.toc-related { margin-top: 24px; padding-top: 16px; border-top: 1px solid var(--border-color); display: none; }
.toc-related.visible { display: block; }
.toc-related-title { font-size: 0.8rem; font-weight: 700; color: var(--text-tertiary); text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 10px; }

/* Loading Placeholder */
.loading-placeholder {
  text-align: center;
  padding: 60px;
  color: var(--text-tertiary);
}
.toc-related-item {
  display: block; padding: 4px 0; font-size: 0.82rem;
  color: var(--text-link); text-decoration: none;
  transition: all var(--transition);
}
.toc-related-item:hover { color: var(--accent-hover); }

/* Help Content Styling */
.help-content h1 { font-size: 2rem; font-weight: 800; margin-bottom: 24px; padding-bottom: 12px; border-bottom: 2px solid var(--border-color); letter-spacing: -0.02em; }
.help-content h2 { 
  font-size: 1.5rem; 
  font-weight: 700; 
  margin-top: 48px; 
  margin-bottom: 20px; 
  padding-bottom: 12px; 
  padding-left: 16px;
  border-bottom: 1px solid var(--border-color); 
  color: var(--text-primary); 
  scroll-margin-top: 80px;
  letter-spacing: -0.01em;
  position: relative;
}
.help-content h2::before {
  content: '';
  position: absolute;
  left: 0;
  top: 6px;
  bottom: 12px;
  width: 4px;
  background: linear-gradient(180deg, var(--accent), #7c3aed);
  border-radius: 4px;
}
.help-content h3 { 
  font-size: 1.2rem; 
  font-weight: 700; 
  margin-top: 32px; 
  margin-bottom: 16px; 
  color: var(--text-primary); 
  scroll-margin-top: 80px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.help-content h3::before {
  content: '';
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
  flex-shrink: 0;
}

[data-theme="dark"] .help-content h1,
[data-theme="dark"] .help-content h2,
[data-theme="dark"] .help-content h3 {
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--text-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.help-content p { margin-bottom: 16px; color: var(--text-primary); font-size: 0.95rem; line-height: 1.8; }
.help-content ul, .help-content ol { margin-bottom: 16px; padding-left: 24px; }
.help-content li { margin-bottom: 8px; color: var(--text-primary); font-size: 0.95rem; line-height: 1.8; }
.help-content li::marker { color: var(--accent); font-weight: 600; }
.help-content .text-block { 
  margin-bottom: 16px; 
  color: var(--text-primary); 
  font-size: 0.95rem; 
  line-height: 1.8;
  letter-spacing: 0.01em;
}

/* 强调文字 */
.help-content strong { 
  color: var(--text-primary); 
  font-weight: 700; 
  background: var(--accent-bg);
  padding: 1px 6px;
  border-radius: 4px;
}
.help-content em { 
  color: var(--accent); 
  font-style: italic; 
  font-weight: 500;
}

/* 链接样式 */
.help-content a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: all 0.2s ease;
  font-weight: 500;
}
.help-content a:hover {
  color: var(--accent-hover);
  border-bottom-color: var(--accent);
}

/* 代码样式 */
.help-content code {
  background: var(--bg-code);
  padding: 2px 8px;
  border-radius: 6px;
  font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
  font-size: 0.88rem;
  color: var(--accent);
  border: 1px solid var(--border-light);
}

/* 引用样式 */
.help-content blockquote {
  margin: 16px 0;
  padding: 12px 20px;
  background: var(--bg-secondary);
  border-left: 4px solid var(--accent);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  color: var(--text-secondary);
  font-style: italic;
}

/* 参数介绍卡片样式 */
.help-content .param-intro {
  position: relative;
  padding: 16px 20px 16px 52px;
  margin-bottom: 20px;
  background: var(--accent-light);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  color: var(--text-primary);
  font-size: 0.95rem;
  line-height: 1.7;
}

.help-content .param-intro::before {
  content: 'ℹ️';
  position: absolute;
  left: 18px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 1.2rem;
}

.help-content .param-intro::after {
  content: '';
  position: absolute;
  left: 0;
  top: 12px;
  bottom: 12px;
  width: 4px;
  background: linear-gradient(180deg, var(--accent), #7c3aed);
  border-radius: 0 4px 4px 0;
}

/* 深色主题下的参数介绍 */
[data-theme="dark"] .help-content .param-intro {
  background: rgba(59, 130, 246, 0.1);
  border-color: rgba(59, 130, 246, 0.2);
}

.help-content .link-block { margin-bottom: 12px; }
.help-content .link-block a { display: inline-flex; align-items: center; gap: 6px; }
.help-content .faq-item { margin-bottom: 20px; padding: 20px; background: var(--bg-secondary); border-radius: var(--radius-md); border: 1px solid var(--border-color); transition: all 0.3s ease; }
.help-content .faq-item:hover {
  border-color: var(--accent);
  box-shadow: 0 4px 12px var(--accent-light);
}
.help-content .faq-item .question { font-weight: 700; color: var(--text-primary); margin-bottom: 12px; font-size: 1rem; line-height: 1.6; }
.help-content .faq-item .answer { color: var(--text-primary); line-height: 1.8; font-size: 0.95rem; }
.help-content .steps-block { margin-bottom: 20px; }
.help-content .steps-block .step { display: flex; gap: 14px; margin-bottom: 14px; transition: all 0.2s ease; padding: 8px 10px; border-radius: 10px; }
.help-content .steps-block .step:hover {
  background: var(--accent-bg);
}
.help-content .steps-block .step-num {
  width: 30px; height: 30px; flex-shrink: 0;
  background: linear-gradient(135deg, #3b82f6, #8b5cf6);
  color: #fff; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 0.85rem; font-weight: 700;
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.3);
  transition: all 0.3s ease;
}
.help-content .steps-block .step:hover .step-num {
  transform: scale(1.1);
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}
.help-content .steps-block .step-text { color: var(--text-primary); font-size: 0.95rem; line-height: 1.8; padding-top: 2px; }

/* Images */
.help-content .image-block {
  margin: 16px 0; text-align: center;
}
.help-content .image-block img {
  max-width: 100%; border-radius: var(--radius-md);
  border: 1px solid var(--border-color); cursor: zoom-in;
  transition: all var(--transition);
}
.help-content .image-block img:hover { box-shadow: var(--shadow-md); }
.help-content .image-block .image-caption {
  font-size: 0.85rem; 
  color: var(--text-secondary); 
  margin-top: 12px;
  text-align: center;
  font-style: italic;
  position: relative;
  padding-top: 10px;
}
.help-content .image-block .image-caption::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 40px;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
  border-radius: 2px;
}

/* Image Lightbox */
.lightbox {
  position: fixed; top: 0; left: 0; width: 100%; height: 100%;
  background: rgba(0,0,0,0.85); z-index: 1000;
  display: flex; align-items: center; justify-content: center;
  opacity: 0; pointer-events: none; transition: opacity 0.3s;
}
.lightbox.active { opacity: 1; pointer-events: all; }
.lightbox img { max-width: 92%; max-height: 92%; border-radius: var(--radius-md); }
.lightbox-close {
  position: absolute; top: 20px; right: 20px;
  width: 40px; height: 40px; border: none; background: rgba(255,255,255,0.15);
  color: #fff; font-size: 1.3rem; border-radius: 50%; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: background var(--transition);
}
.lightbox-close:hover { background: rgba(255,255,255,0.3); }

/* ===== Parameter Display (Modern Style) ===== */
/* ===== Parameter List - Tech Dark Style (New) ===== */
.param-list {
  margin: 20px 0 28px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.param-row {
  position: relative;
  display: flex;
  flex-direction: column;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  opacity: 0;
  transform: translateY(15px);
  animation: paramFadeIn 0.4s ease forwards;
}
.param-row:nth-child(1) { animation-delay: 0.02s; }
.param-row:nth-child(2) { animation-delay: 0.04s; }
.param-row:nth-child(3) { animation-delay: 0.06s; }
.param-row:nth-child(4) { animation-delay: 0.08s; }
.param-row:nth-child(5) { animation-delay: 0.1s; }
.param-row:nth-child(6) { animation-delay: 0.12s; }
.param-row:nth-child(7) { animation-delay: 0.14s; }
.param-row:nth-child(8) { animation-delay: 0.16s; }
.param-row:nth-child(9) { animation-delay: 0.18s; }
.param-row:nth-child(10) { animation-delay: 0.2s; }

@keyframes paramFadeIn {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}
.param-row::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, #3b82f6, #8b5cf6, #06b6d4);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s ease;
}
.param-row::after {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(59, 130, 246, 0.03), transparent);
  transition: left 0.6s ease;
  pointer-events: none;
}
.param-row:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 24px rgba(0, 0, 0, 0.15), 0 0 30px rgba(59, 130, 246, 0.08);
  border-color: var(--accent);
}
.param-row:hover::before {
  transform: scaleX(1);
}
.param-row:hover::after {
  left: 100%;
}
.param-row.expanded {
  background: var(--bg-card);
}
.param-header {
  display: flex;
  align-items: center;
  padding: 16px;
  cursor: pointer;
  gap: 12px;
  user-select: none;
  transition: all 0.2s ease;
}
.param-icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  font-size: 1.1rem;
  background: var(--accent-bg);
  color: var(--accent);
  flex-shrink: 0;
  transition: all 0.3s ease;
  box-shadow: 0 4px 12px var(--accent-light);
}
.param-row:hover .param-icon {
  transform: scale(1.1) rotate(-3deg);
  box-shadow: 0 8px 20px var(--accent-light);
}
.param-icon.type-date {
  background: rgba(5, 150, 105, 0.1);
  color: #059669;
}
.param-icon.type-number {
  background: rgba(217, 119, 6, 0.1);
  color: #d97706;
}
.param-icon.type-boolean {
  background: rgba(124, 58, 237, 0.1);
  color: #7c3aed;
}
.param-icon.type-file {
  background: rgba(8, 145, 178, 0.1);
  color: #0891b2;
}
.param-icon.type-array {
  background: rgba(220, 38, 38, 0.1);
  color: #dc2626;
}
.param-icon.type-object {
  background: rgba(101, 163, 13, 0.1);
  color: #65a30d;
}
.param-info {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.param-name {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.4;
  word-break: break-word;
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--text-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.param-type-badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  font-size: 0.72rem;
  font-weight: 600;
  color: #fff;
  background: linear-gradient(135deg, #3b82f6, #8b5cf6);
  border-radius: 999px;
  width: fit-content;
  flex-shrink: 0;
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.3);
  letter-spacing: 0.02em;
}
.param-arrow {
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-tertiary);
  transition: transform 0.3s ease;
  flex-shrink: 0;
  opacity: 0.5;
}
.param-row.expanded .param-arrow {
  transform: rotate(180deg);
  color: var(--accent);
}
.param-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1), 
              padding 0.4s cubic-bezier(0.4, 0, 0.2, 1),
              opacity 0.3s ease;
  padding: 0 16px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  opacity: 0;
}
.param-row.expanded .param-content {
  max-height: 800px;
  padding: 0 16px 20px;
  opacity: 1;
}
.param-value-row {
  display: flex;
  align-items: flex-start;
  gap: 10px;
}
.param-value-label {
  font-size: 0.7rem;
  font-weight: 700;
  color: var(--text-tertiary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding-top: 6px;
  min-width: 50px;
  flex-shrink: 0;
}
.param-value {
  display: inline-flex;
  align-items: center;
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-bg);
  padding: 6px 14px;
  border-radius: 8px;
  border: 1px solid var(--accent-light);
  word-break: break-all;
  box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.05);
}
.param-desc {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.7;
  white-space: pre-line;
  margin: 0;
  padding: 10px 0 0;
  border-top: 1px solid var(--border-light);
}
.param-options {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: flex-start;
  padding-top: 4px;
}
.param-options-label {
  width: 100%;
  color: var(--text-tertiary);
  font-weight: 700;
  margin-bottom: 4px;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.param-option-tag {
  display: inline-flex;
  align-items: center;
  padding: 5px 12px;
  background: var(--bg-secondary);
  border-radius: 8px;
  font-size: 0.78rem;
  font-family: "SFMono-Regular", Consolas, monospace;
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  transition: all 0.2s ease;
  word-break: break-all;
  cursor: default;
}
.param-option-tag:hover {
  background: var(--accent-bg);
  color: var(--accent);
  border-color: var(--accent);
  transform: translateY(-1px);
  box-shadow: 0 2px 8px var(--accent-light);
}

@media (max-width: 900px) {
  .param-list {
    grid-template-columns: 1fr;
    gap: 16px;
  }
}

@media (max-width: 768px) {
  .param-header {
    padding: 16px;
    gap: 12px;
  }
  .param-icon {
    width: 36px;
    height: 36px;
    font-size: 1rem;
  }
  .param-content {
    padding: 0 16px 16px;
  }
  .param-value-row {
    flex-direction: column;
    gap: 6px;
  }
  .param-value-label {
    min-width: auto;
    padding-top: 0;
  }
}

/* Tables (keep for reference tables like data info, GOCI2 products) */
.help-content .table-wrapper {
  margin: 20px 0; overflow-x: auto; border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
}
.help-content table {
  width: 100%; border-collapse: collapse; font-size: 0.9rem;
}
.help-content thead { background: var(--bg-tertiary); }
.help-content th {
  padding: 12px 16px; text-align: left; font-weight: 700;
  color: var(--text-primary); border-bottom: 2px solid var(--border-color);
  white-space: nowrap;
  font-size: 0.88rem;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}
.help-content td {
  padding: 12px 16px; border-bottom: 1px solid var(--border-light);
  color: var(--text-primary); vertical-align: top;
  line-height: 1.7;
}
.help-content tr:last-child td { border-bottom: none; }
.help-content tr:hover td { background: var(--accent-bg); }
.help-content td:first-child { font-weight: 600; color: var(--text-primary); white-space: nowrap; }

/* ===== Responsive ===== */
@media (max-width: 1200px) {
  .help-toc { display: none; }
  .help-content { max-width: 100%; }
}
@media (max-width: 900px) {
  .help-sidebar {
    transform: translateX(-100%); transition: transform 0.3s;
    width: 280px; box-shadow: var(--shadow-xl);
  }
  .help-sidebar.open { transform: translateX(0); }
  .help-main { margin-left: 0; width: 100%; }
  .help-content { padding: 24px 20px; max-width: 100%; width: 100%; }
  .mobile-menu-btn { display: flex; }
  .sidebar-overlay {
    position: fixed; top: var(--header-height); left: 0; right: 0; bottom: 0;
    background: rgba(0,0,0,0.4); z-index: 49; display: none;
  }
  .sidebar-overlay.active { display: block; }
  .hero h1 { font-size: 2rem; }
  .hero .subtitle { font-size: 1rem; }
  .carousel-slide { flex-direction: column; padding: 30px 20px; text-align: center; }
  .header-nav { display: none; }
  .search-container { margin: 0 12px; }
  .purchase-grid { grid-template-columns: 1fr; }
  
  /* Header mobile */
  .header-logo span:last-child {
    display: none;
  }
  .header-logo {
    font-size: 1rem;
  }
  
  /* Search mobile */
  .search-input {
    font-size: 0.85rem;
  }
  .search-shortcut {
    display: none;
  }
  
  /* 移动端隐藏拖拽线 */
  .resizer {
    display: none;
  }
}
@media (max-width: 600px) {
  .hero h1 { font-size: 1.6rem; }
  .download-card { padding: 30px 20px; }
  .download-card h2 { font-size: 1.4rem; }
  .features-grid { grid-template-columns: 1fr; }
  
  /* Header small mobile */
  .header-inner {
    padding: 0 12px;
  }
  .header-actions {
    gap: 4px;
  }
  .theme-toggle, .lang-toggle {
    width: 32px;
    height: 32px;
    font-size: 0.8rem;
  }
  .mobile-menu-btn {
    width: 32px;
    height: 32px;
    font-size: 1rem;
  }
  
  /* Search small mobile */
  .search-container {
    margin: 0 8px;
  }
  .search-input-wrapper {
    height: 36px;
  }
  .search-icon {
    font-size: 0.9rem;
  }
  .search-input {
    font-size: 0.8rem;
    padding: 0 32px;
  }
  
  /* Content mobile */
  .help-content {
    padding: 20px 16px;
  }
  .help-content h1 {
    font-size: 1.5rem;
  }
  .help-content h2 {
    font-size: 1.25rem;
  }
  .help-content h3 {
    font-size: 1.1rem;
  }
  .help-content p {
    font-size: 0.9rem;
    line-height: 1.7;
  }
  
  /* Images mobile */
  .help-content img {
    max-width: 100%;
    height: auto;
  }
  
  /* Back to top mobile */
  #backToTop.back-to-top {
    bottom: 20px;
    right: 20px;
    width: 42px;
    height: 42px;
    font-size: 1.1rem;
  }
  
  /* Steps mobile */
  .steps-list li {
    padding-left: 40px;
  }
  .steps-list li::before {
    width: 28px;
    height: 28px;
    font-size: 0.8rem;
    left: 0;
  }
  
  /* FAQ mobile */
  .faq-item {
    padding: 16px;
  }
  .faq-question {
    font-size: 0.95rem;
  }
  
  /* Param list mobile */
  .param-row {
    border-radius: 12px;
  }
  .param-header {
    padding: 14px;
  }
  .param-name {
    font-size: 0.85rem;
  }
  .param-icon {
    width: 36px;
    height: 36px;
    font-size: 1rem;
  }
  .param-content {
    padding: 0 14px;
  }
  .param-value-row {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }
  .param-value-label {
    font-size: 0.75rem;
  }
  .param-value {
    font-size: 0.85rem;
    padding: 6px 10px;
  }
  
  /* Table mobile */
  .table-wrapper {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    margin: 0 -16px;
    padding: 0 16px;
  }
  table {
    font-size: 0.8rem;
    min-width: 500px;
  }
  th, td {
    padding: 8px 10px;
  }
  
  /* Search results mobile */
  .search-results {
    max-height: 60vh;
  }
  .search-result-item {
    padding: 10px 12px;
  }
  .search-result-title {
    font-size: 0.85rem;
  }
  .search-result-preview {
    font-size: 0.75rem;
  }
  
  /* TOC mobile */
  .toc-panel {
    display: none;
  }
  
  /* Sidebar mobile drawer - 小屏幕优化 */
  .help-sidebar {
    width: 260px;
    z-index: 10000;
  }
  
}

/* ===== Back to Top Button ===== */
#backToTop.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 50%, #06b6d4 100%);
  background-size: 200% 200%;
  color: #fff;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  font-weight: bold;
  box-shadow: 0 4px 20px rgba(59, 130, 246, 0.5);
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px) scale(0.9);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  z-index: 9999 !important;
  animation: gradientShift 3s ease infinite;
  pointer-events: none;
}

#backToTop.back-to-top::before {
  content: '';
  position: absolute;
  top: -4px;
  left: -4px;
  right: -4px;
  bottom: -4px;
  border-radius: 50%;
  background: linear-gradient(135deg, #3b82f6, #8b5cf6, #06b6d4);
  filter: blur(12px);
  opacity: 0;
  transition: opacity 0.3s ease;
  z-index: -1;
}

#backToTop.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0) scale(1);
  pointer-events: auto;
}

#backToTop.back-to-top:hover {
  transform: translateY(-4px) scale(1.1);
  box-shadow: 0 8px 30px rgba(59, 130, 246, 0.6);
}

#backToTop.back-to-top:hover::before {
  opacity: 0.7;
}

#backToTop.back-to-top:active {
  transform: translateY(-2px) scale(1.05);
}

/* ===== Scroll Progress Bar ===== */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 2px;
  background: linear-gradient(90deg, #3b82f6 0%, #8b5cf6 50%, #06b6d4 100%);
  z-index: 101;
  transition: width 0.1s ease;
  box-shadow: 0 0 8px rgba(59, 130, 246, 0.5);
}

/* ===== Animations ===== */
@keyframes gradientShift {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

@keyframes float {
  0%, 100% { transform: translateY(0px); }
  50% { transform: translateY(-10px); }
}

@keyframes pulse-glow {
  0%, 100% { box-shadow: 0 0 20px rgba(59, 130, 246, 0.3); }
  50% { box-shadow: 0 0 40px rgba(59, 130, 246, 0.6); }
}

@keyframes shimmer {
  0% { background-position: -200% center; }
  100% { background-position: 200% center; }
}

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

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.9);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

/* ===== Scroll Reveal Animations ===== */
.reveal {
  opacity: 0;
  transform: translateY(15px);
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}
.reveal.active {
  opacity: 1;
  transform: translateY(0);
}
.reveal-left {
  opacity: 0;
  transform: translateX(-15px);
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}
.reveal-left.active {
  opacity: 1;
  transform: translateX(0);
}
.reveal-right {
  opacity: 0;
  transform: translateX(15px);
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}
.reveal-right.active {
  opacity: 1;
  transform: translateX(0);
}
.reveal-scale {
  opacity: 0;
  transform: scale(0.97);
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}
.reveal-scale.active {
  opacity: 1;
  transform: scale(1);
}

/* ===== Cursor Glow Effect ===== */
.cursor-glow {
  position: fixed;
  width: 250px;
  height: 250px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(59, 130, 246, 0.08) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
  transform: translate(-50%, -50%);
  transition: opacity 0.3s ease;
  opacity: 0;
}
.cursor-glow.visible {
  opacity: 1;
}

/* ===== Ripple Effect ===== */
.ripple {
  position: relative;
  overflow: hidden;
}
.ripple::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.3);
  transform: translate(-50%, -50%);
  transition: width 0.6s ease, height 0.6s ease, opacity 0.6s ease;
  opacity: 0;
}
.ripple:active::after {
  width: 300px;
  height: 300px;
  opacity: 1;
  transition: 0s;
}

/* ===== Enhanced Header ===== */
.site-header {
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}
.site-header.scrolled {
  box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}

/* ===== Enhanced Sidebar - Rounded Style ===== */
.help-sidebar {
  scrollbar-width: thin;
  scrollbar-color: transparent transparent;
  padding: 12px 8px;
}
.help-sidebar:hover {
  scrollbar-color: var(--border-color) transparent;
}

/* Sidebar section title */
.sidebar-section-title {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--text-tertiary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 12px 14px 6px;
}

/* Level 1 items have a subtle background */
.sidebar-item.level-1::before {
  content: '';
  display: none;
}

/* Add subtle icon placeholder for level 1 */
.sidebar-item.level-1 {
  position: relative;
}

/* Active state glow effect */
.sidebar-item.active {
  position: relative;
  overflow: hidden;
}
.sidebar-item.active::after {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
  animation: shimmer 2s infinite;
}
@keyframes shimmer {
  0% { left: -100%; }
  100% { left: 100%; }
}

/* ===== Enhanced TOC ===== */
.toc-item {
  position: relative;
  transition: all 0.2s ease;
}
.toc-item::before {
  content: '';
  position: absolute;
  left: -2px;
  top: 50%;
  transform: translateY(-50%);
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--border-color);
  transition: all 0.2s ease;
}
.toc-item.active::before {
  background: var(--accent);
  box-shadow: 0 0 0 4px var(--accent-light);
}

/* ===== Enhanced Content Cards ===== */
.help-content .faq-item {
  transition: all 0.2s ease;
  position: relative;
  overflow: hidden;
}
.help-content .faq-item::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: linear-gradient(180deg, var(--accent) 0%, #7c3aed 100%);
  border-radius: 4px 0 0 4px;
  opacity: 0;
  transition: opacity 0.2s ease;
}
.help-content .faq-item:hover {
  transform: translateX(4px);
  box-shadow: var(--shadow-md);
}
.help-content .faq-item:hover::before {
  opacity: 1;
}

/* ===== Enhanced Steps ===== */
.help-content .steps-block .step-num {
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.3);
  transition: transform 0.2s ease;
}
.help-content .steps-block .step:hover .step-num {
  transform: scale(1.1);
}

/* ===== Enhanced Images ===== */
.help-content .image-block img {
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}
.help-content .image-block img:hover {
  transform: scale(1.02);
  box-shadow: 0 8px 24px rgba(0,0,0,0.12);
}

/* ===== Enhanced Tables ===== */
.help-content table {
  transition: all 0.2s ease;
}
.help-content tbody tr {
  transition: all 0.2s ease;
}
.help-content tbody tr:hover {
  background: var(--accent-bg);
}

/* ===== Code Block Enhancement ===== */
pre {
  position: relative;
  border: 1px solid var(--border-color);
  transition: all 0.2s ease;
}
pre:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow-md);
}
code {
  transition: all 0.2s ease;
}
code:hover {
  background: var(--accent-light);
  color: var(--accent);
}

/* ===== Search Enhancement ===== */
.search-input {
  transition: all 0.2s ease;
}
.search-input:focus {
  transform: translateY(-1px);
}

/* ===== Animations ===== */
@keyframes fadeInUp { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: translateY(0); } }
.animate-in { animation: fadeInUp 0.5s ease forwards; }

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}
.animate-pulse { animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite; }

/* ===== Smooth Scrollbar for whole page ===== */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}
::-webkit-scrollbar-track {
  background: transparent;
}
::-webkit-scrollbar-thumb {
  background: var(--border-color);
  border-radius: 4px;
  transition: background 0.2s ease;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--text-tertiary);
}

/* ===== Selection Color ===== */
::selection {
  background: var(--accent-light);
  color: var(--accent);
}

/* ===== Dark mode adjustments ===== */
[data-theme="dark"] .back-to-top {
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.5);
}
[data-theme="dark"] .back-to-top:hover {
  box-shadow: 0 8px 20px rgba(59, 130, 246, 0.6);
}
[data-theme="dark"] .help-content .image-block img:hover {
  box-shadow: 0 8px 24px rgba(0,0,0,0.4);
}
[data-theme="dark"] .site-header.scrolled {
  box-shadow: 0 4px 12px rgba(0,0,0,0.3);
}