:root {
  --brand-primary: #FF8C42;
  --brand-primary-dark: #E06A1A;
  --brand-primary-light: #FFB07C;
  --brand-secondary: #2E86AB;
  --brand-secondary-dark: #1F5E7A;
  --brand-accent: #6B4EAA;
  --bg-page: #FFFFFF;
  --bg-section: #F8F9FA;
  --bg-card: #FFFFFF;
  --bg-nav: rgba(255, 255, 255, 0.82);
  --bg-footer: #1A1E24;
  --bg-footer-card: #252B33;
  --bg-glass: rgba(255, 255, 255, 0.6);
  --bg-glass-border: rgba(255, 255, 255, 0.5);
  --text-primary: #17202A;
  --text-secondary: #334155;
  --text-muted: #4B5563;
  --text-light: #6B7280;
  --text-on-dark: #E5E7EB;
  --text-on-dark-muted: #9CA3AF;
  --text-on-brand: #FFFFFF;
  --border-color: #E5E7EB;
  --border-light: #F3F4F6;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
  --shadow-glow: 0 0 24px rgba(255, 140, 66, 0.35);
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --transition: all 0.3s ease;
  --transition-slow: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
}

[data-theme="dark"] {
  --bg-page: #0F1419;
  --bg-section: #1A1F26;
  --bg-card: #1E242C;
  --bg-nav: rgba(21, 26, 33, 0.82);
  --bg-footer: #0A0E12;
  --bg-footer-card: #1A1F26;
  --bg-glass: rgba(30, 36, 44, 0.6);
  --bg-glass-border: rgba(255, 255, 255, 0.08);
  --text-primary: #F1F5F9;
  --text-secondary: #E2E8F0;
  --text-muted: #CBD5E1;
  --text-light: #94A3B8;
  --text-on-dark: #F1F5F9;
  --text-on-dark-muted: #A0AEC0;
  --text-on-brand: #FFFFFF;
  --border-color: #2D3748;
  --border-light: #1E242C;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);
  --shadow-glow: 0 0 28px rgba(255, 140, 66, 0.25);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-page);
  color: var(--text-primary);
  line-height: 1.75;
  font-size: 16px;
  transition: background-color 0.35s ease, color 0.35s ease;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ===== 导航吸顶 + 毛玻璃 ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: var(--bg-nav);
  backdrop-filter: blur(16px) saturate(1.6);
  -webkit-backdrop-filter: blur(16px) saturate(1.6);
  border-bottom: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
  transition: background-color 0.35s ease, border-color 0.35s ease, box-shadow 0.35s ease;
}

.nav-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  flex-shrink: 0;
  transition: var(--transition);
}

.logo:hover {
  transform: scale(1.04);
}

.logo svg {
  width: 36px;
  height: 36px;
  transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.logo:hover svg {
  transform: rotate(-12deg) scale(1.08);
}

.logo-text {
  font-size: 20px;
  font-weight: 700;
  color: var(--brand-primary-dark);
  letter-spacing: 0.5px;
  transition: color 0.35s ease;
}

[data-theme="dark"] .logo-text {
  color: var(--brand-primary);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  list-style: none;
}

.nav-links a {
  display: block;
  padding: 8px 14px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 15px;
  font-weight: 500;
  border-radius: var(--radius-sm);
  transition: var(--transition);
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 2px;
  left: 50%;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--brand-primary), var(--brand-primary-light));
  border-radius: 2px;
  transition: width 0.3s ease, left 0.3s ease;
}

.nav-links a:hover::after,
.nav-links a:focus::after {
  width: 60%;
  left: 20%;
}

.nav-links a:hover,
.nav-links a:focus {
  color: var(--brand-primary-dark);
  background-color: rgba(255, 140, 66, 0.08);
}

[data-theme="dark"] .nav-links a:hover,
[data-theme="dark"] .nav-links a:focus {
  color: var(--brand-primary);
  background-color: rgba(255, 140, 66, 0.15);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

/* 搜索框 毛玻璃 */
.search-box {
  display: flex;
  align-items: center;
  background-color: var(--bg-glass);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--bg-glass-border);
  border-radius: var(--radius-sm);
  padding: 0 10px;
  height: 36px;
  transition: var(--transition);
}

.search-box:focus-within {
  border-color: var(--brand-primary);
  box-shadow: 0 0 0 2px rgba(255, 140, 66, 0.2), var(--shadow-glow);
}

.search-box input {
  border: none;
  background: transparent;
  outline: none;
  color: var(--text-primary);
  font-size: 14px;
  width: 140px;
  font-family: inherit;
}

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

.search-box button {
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  display: flex;
  align-items: center;
  color: var(--text-muted);
  transition: var(--transition);
}

.search-box button:hover {
  color: var(--brand-primary-dark);
  transform: scale(1.15);
}

[data-theme="dark"] .search-box button:hover {
  color: var(--brand-primary);
}

/* 主题切换按钮 */
.theme-toggle {
  background: var(--bg-glass);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--bg-glass-border);
  border-radius: var(--radius-sm);
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-secondary);
  transition: var(--transition);
}

.theme-toggle:hover {
  border-color: var(--brand-primary);
  color: var(--brand-primary-dark);
  transform: rotate(20deg) scale(1.08);
  box-shadow: var(--shadow-glow);
}

[data-theme="dark"] .theme-toggle:hover {
  color: var(--brand-primary);
}

.mobile-menu-btn {
  display: none;
  background: var(--bg-glass);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--bg-glass-border);
  border-radius: var(--radius-sm);
  width: 36px;
  height: 36px;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-secondary);
  transition: var(--transition);
}

.mobile-menu-btn:hover {
  border-color: var(--brand-primary);
  color: var(--brand-primary-dark);
}

/* ===== 移动端菜单 ===== */
.mobile-nav {
  display: none;
  background-color: var(--bg-nav);
  backdrop-filter: blur(16px) saturate(1.6);
  -webkit-backdrop-filter: blur(16px) saturate(1.6);
  border-bottom: 1px solid var(--border-color);
  padding: 12px 20px;
  animation: slideDown 0.3s ease;
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.mobile-nav.open {
  display: block;
}

.mobile-nav a {
  display: block;
  padding: 10px 0;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 15px;
  border-bottom: 1px solid var(--border-light);
  transition: var(--transition);
}

.mobile-nav a:last-child {
  border-bottom: none;
}

.mobile-nav a:hover {
  color: var(--brand-primary-dark);
  padding-left: 6px;
}

[data-theme="dark"] .mobile-nav a:hover {
  color: var(--brand-primary);
}

/* ===== 首屏 Hero 渐变 ===== */
.hero {
  position: relative;
  background: linear-gradient(135deg, #FFF3E9 0%, #FFE8D6 35%, #FFF9F5 70%, #FFF3E9 100%);
  background-size: 200% 200%;
  animation: gradientShift 12s ease infinite;
  padding: 60px 0 50px;
  overflow: hidden;
  transition: background 0.35s ease;
}

@keyframes gradientShift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

[data-theme="dark"] .hero {
  background: linear-gradient(135deg, #1A1410 0%, #2A1F18 35%, #1A1410 70%, #2A1F18 100%);
  background-size: 200% 200%;
  animation: gradientShift 12s ease infinite;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -10%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(255, 140, 66, 0.18) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
  animation: floatOrb 8s ease-in-out infinite;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -8%;
  width: 380px;
  height: 380px;
  background: radial-gradient(circle, rgba(46, 134, 171, 0.12) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
  animation: floatOrb 10s ease-in-out infinite reverse;
}

@keyframes floatOrb {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(-20px, 20px) scale(1.08); }
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 720px;
}

.hero-badge {
  display: inline-block;
  background: linear-gradient(135deg, var(--brand-primary), var(--brand-primary-light));
  color: var(--text-on-brand);
  font-size: 13px;
  font-weight: 600;
  padding: 4px 14px;
  border-radius: 20px;
  margin-bottom: 18px;
  letter-spacing: 0.5px;
  box-shadow: 0 4px 14px rgba(255, 140, 66, 0.35);
  animation: badgePulse 3s ease-in-out infinite;
}

@keyframes badgePulse {
  0%, 100% { box-shadow: 0 4px 14px rgba(255, 140, 66, 0.35); }
  50% { box-shadow: 0 4px 22px rgba(255, 140, 66, 0.55); }
}

.hero h1 {
  font-size: 38px;
  font-weight: 800;
  color: var(--text-primary);
  line-height: 1.3;
  margin-bottom: 18px;
}

.hero h1 .highlight {
  color: var(--brand-primary-dark);
  position: relative;
  display: inline-block;
}

[data-theme="dark"] .hero h1 .highlight {
  color: var(--brand-primary);
}

.hero h1 .highlight::after {
  content: '';
  position: absolute;
  bottom: 2px;
  left: 0;
  width: 100%;
  height: 8px;
  background: linear-gradient(90deg, rgba(255, 140, 66, 0.3), rgba(255, 176, 124, 0.1));
  border-radius: 4px;
  z-index: -1;
}

.hero p {
  font-size: 17px;
  color: var(--text-secondary);
  margin-bottom: 28px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  border: none;
  font-family: inherit;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  background: rgba(255, 255, 255, 0.25);
  border-radius: 50%;
  transform: translate(-50%, -50%);
  transition: width 0.5s ease, height 0.5s ease;
}

.btn:hover::before {
  width: 300px;
  height: 300px;
}

.btn-primary {
  background: linear-gradient(135deg, var(--brand-primary), var(--brand-primary-dark));
  color: var(--text-on-brand);
  box-shadow: 0 4px 14px rgba(255, 140, 66, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(255, 140, 66, 0.45);
}

.btn-outline {
  background-color: transparent;
  color: var(--brand-primary-dark);
  border: 2px solid var(--brand-primary);
}

.btn-outline:hover {
  background: linear-gradient(135deg, var(--brand-primary), var(--brand-primary-dark));
  color: var(--text-on-brand);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(255, 140, 66, 0.35);
}

[data-theme="dark"] .btn-outline {
  color: var(--brand-primary);
  border-color: var(--brand-primary);
}

/* ===== Banner轮播 ===== */
.banner-slider {
  position: relative;
  margin-top: 40px;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  background-color: var(--bg-card);
  transition: box-shadow 0.35s ease;
}

.banner-slider:hover {
  box-shadow: 0 12px 36px rgba(255, 140, 66, 0.2), var(--shadow-lg);
}

.slider-track {
  display: flex;
  transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.slide {
  min-width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 30px;
  text-align: center;
  box-sizing: border-box;
  position: relative;
  overflow: hidden;
}

.slide::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 300px;
  height: 300px;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.2) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

.slide-1 {
  background: linear-gradient(135deg, #FF8C42 0%, #FFB07C 50%, #FF8C42 100%);
  background-size: 200% 200%;
  animation: gradientShift 8s ease infinite;
}

.slide-2 {
  background: linear-gradient(135deg, #2E86AB 0%, #5BAFD6 50%, #2E86AB 100%);
  background-size: 200% 200%;
  animation: gradientShift 8s ease infinite;
}

.slide-3 {
  background: linear-gradient(135deg, #6B4EAA 0%, #9B7FD4 50%, #6B4EAA 100%);
  background-size: 200% 200%;
  animation: gradientShift 8s ease infinite;
}

.slide h2 {
  color: #FFFFFF;
  font-size: 26px;
  font-weight: 700;
  margin-bottom: 10px;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}

.slide p {
  color: #FFFFFF;
  font-size: 16px;
  opacity: 0.95;
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.12);
}

.slider-dots {
  position: absolute;
  bottom: 16px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 8px;
  z-index: 10;
}

.slider-dots span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background-color: rgba(255, 255, 255, 0.5);
  cursor: pointer;
  transition: var(--transition);
}

.slider-dots span:hover {
  background-color: rgba(255, 255, 255, 0.8);
}

.slider-dots span.active {
  background-color: #FFFFFF;
  width: 24px;
  border-radius: 5px;
  box-shadow: 0 0 10px rgba(255, 255, 255, 0.6);
}

/* ===== 通用区块 ===== */
.section {
  padding: 64px 0;
  transition: background-color 0.35s ease;
}

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

.section-header {
  text-align: center;
  margin-bottom: 44px;
}

.section-header h2 {
  font-size: 30px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
  line-height: 1.3;
  position: relative;
  display: inline-block;
}

.section-header h2::after {
  content: '';
  position: absolute;
  bottom: -6px;
  left: 50%;
  transform: translateX(-50%);
  width: 48px;
  height: 3px;
  background: linear-gradient(90deg, var(--brand-primary), var(--brand-primary-light));
  border-radius: 2px;
}

.section-header p {
  font-size: 16px;
  color: var(--text-muted);
  max-width: 640px;
  margin: 0 auto;
  line-height: 1.8;
}

/* ===== 卡片网格 ===== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  transition: var(--transition);
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--brand-primary), var(--brand-primary-light), var(--brand-secondary));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s ease;
}

.card:hover::before {
  transform: scaleX(1);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md), 0 0 0 1px rgba(255, 140, 66, 0.1);
  border-color: var(--brand-primary-light);
}

.card-icon {
  width: 48px;
  height: 48px;
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, #FFF3E9, #FFE8D6);
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.card:hover .card-icon {
  transform: scale(1.1) rotate(-6deg);
  box-shadow: 0 4px 14px rgba(255, 140, 66, 0.25);
}

[data-theme="dark"] .card-icon {
  background: linear-gradient(135deg, #2A1F18, #3A2A1E);
}

.card h3 {
  font-size: 19px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 10px;
}

.card p {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.75;
}

/* ===== 文章列表 ===== */
.article-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 24px;
}

.article-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
  transition: var(--transition);
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
}

.article-card::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--brand-primary), var(--brand-secondary));
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.4s ease;
}

.article-card:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

.article-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--brand-primary-light);
}

.article-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
  font-size: 13px;
  color: var(--text-light);
}

.article-tag {
  display: inline-block;
  background: linear-gradient(135deg, rgba(255, 140, 66, 0.15), rgba(255, 176, 124, 0.1));
  color: var(--brand-primary-dark);
  font-size: 12px;
  font-weight: 600;
  padding: 2px 10px;
  border-radius: 12px;
  transition: var(--transition);
}

.article-card:hover .article-tag {
  background: linear-gradient(135deg, var(--brand-primary), var(--brand-primary-light));
  color: #FFFFFF;
}

[data-theme="dark"] .article-tag {
  background: linear-gradient(135deg, rgba(255, 140, 66, 0.25), rgba(255, 176, 124, 0.15));
  color: var(--brand-primary-light);
}

.article-card h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 10px;
  line-height: 1.4;
  transition: color 0.3s ease;
}

.article-card:hover h3 {
  color: var(--brand-primary-dark);
}

[data-theme="dark"] .article-card:hover h3 {
  color: var(--brand-primary);
}

.article-card p {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.7;
  flex: 1;
  margin-bottom: 14px;
}

.read-more {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--brand-primary-dark);
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  transition: var(--transition);
}

.read-more:hover {
  gap: 10px;
  color: var(--brand-primary);
}

[data-theme="dark"] .read-more {
  color: var(--brand-primary);
}

/* ===== FAQ ===== */
.faq-list {
  max-width: 860px;
  margin: 0 auto;
}

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

.faq-item:hover {
  border-color: var(--brand-primary-light);
  box-shadow: var(--shadow-sm);
}

.faq-item.open {
  border-color: var(--brand-primary);
  box-shadow: 0 0 0 1px rgba(255, 140, 66, 0.15), var(--shadow-sm);
}

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 22px;
  cursor: pointer;
  background: none;
  border: none;
  width: 100%;
  text-align: left;
  font-family: inherit;
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
  gap: 16px;
  transition: var(--transition);
}

.faq-question:hover {
  color: var(--brand-primary-dark);
}

[data-theme="dark"] .faq-question:hover {
  color: var(--brand-primary);
}

.faq-icon {
  flex-shrink: 0;
  width: 22px;
  height: 22px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  color: var(--text-muted);
}

.faq-item.open .faq-icon {
  transform: rotate(180deg);
  color: var(--brand-primary);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.45s cubic-bezier(0.4, 0, 0.2, 1), padding 0.35s ease;
  padding: 0 22px;
}

.faq-item.open .faq-answer {
  max-height: 500px;
  padding: 0 22px 20px;
}

.faq-answer p {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* ===== HowTo ===== */
.howto-steps {
  max-width: 860px;
  margin: 0 auto;
  counter-reset: step;
}

.howto-step {
  position: relative;
  padding-left: 64px;
  padding-bottom: 32px;
  border-left: 2px solid var(--border-color);
  margin-left: 24px;
  transition: var(--transition);
}

.howto-step:last-child {
  border-left-color: transparent;
  padding-bottom: 0;
}

.howto-step:hover {
  border-left-color: var(--brand-primary-light);
}

.howto-step::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: -25px;
  top: 0;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--brand-primary), var(--brand-primary-dark));
  color: var(--text-on-brand);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  font-weight: 700;
  box-shadow: 0 0 0 4px var(--bg-page), 0 4px 12px rgba(255, 140, 66, 0.3);
  transition: var(--transition);
}

.howto-step:hover::before {
  transform: scale(1.1);
  box-shadow: 0 0 0 4px var(--bg-page), 0 6px 18px rgba(255, 140, 66, 0.45);
}

.howto-step h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
  padding-top: 12px;
}

.howto-step p {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.8;
}

/* ===== 数据统计 ===== */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 24px;
  text-align: center;
}

.stat-item {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 32px 20px;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.stat-item::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, rgba(255, 140, 66, 0.05), transparent);
  opacity: 0;
  transition: opacity 0.4s ease;
}

.stat-item:hover::before {
  opacity: 1;
}

.stat-item:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--brand-primary-light);
}

.stat-number {
  font-size: 36px;
  font-weight: 800;
  color: var(--brand-primary-dark);
  line-height: 1.2;
  margin-bottom: 8px;
  position: relative;
  z-index: 1;
}

[data-theme="dark"] .stat-number {
  color: var(--brand-primary);
}

.stat-label {
  font-size: 15px;
  color: var(--text-muted);
  font-weight: 500;
  position: relative;
  z-index: 1;
}

/* ===== 案例/评价 ===== */
.testimonial-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.testimonial-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  position: relative;
}

.testimonial-card::before {
  content: '"';
  position: absolute;
  top: 12px;
  right: 20px;
  font-size: 60px;
  line-height: 1;
  color: rgba(255, 140, 66, 0.12);
  font-family: Georgia, serif;
  pointer-events: none;
}

.testimonial-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--brand-primary-light);
}

.testimonial-card p {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 18px;
  font-style: italic;
  position: relative;
  z-index: 1;
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 12px;
}

.testimonial-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  font-weight: 700;
  color: #FFFFFF;
  flex-shrink: 0;
  transition: var(--transition);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}

.testimonial-card:hover .testimonial-avatar {
  transform: scale(1.1);
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.2);
}

.testimonial-name {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-primary);
}

.testimonial-role {
  font-size: 13px;
  color: var(--text-light);
}

/* ===== 友情链接 ===== */
.friend-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

.friend-links a {
  display: inline-block;
  padding: 8px 18px;
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 14px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.friend-links a::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 140, 66, 0.1), transparent);
  transition: left 0.5s ease;
}

.friend-links a:hover::before {
  left: 100%;
}

.friend-links a:hover {
  border-color: var(--brand-primary);
  color: var(--brand-primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(255, 140, 66, 0.15);
}

[data-theme="dark"] .friend-links a:hover {
  color: var(--brand-primary);
}

/* ===== 页脚 ===== */
.site-footer {
  background: linear-gradient(180deg, var(--bg-footer) 0%, #0F1318 100%);
  color: var(--text-on-dark);
  padding: 56px 0 0;
  position: relative;
  overflow: hidden;
}

.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--brand-primary), transparent);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 36px;
  padding-bottom: 40px;
}

.footer-col h4 {
  font-size: 16px;
  font-weight: 700;
  color: var(--text-on-dark);
  margin-bottom: 16px;
  position: relative;
  display: inline-block;
}

.footer-col h4::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 24px;
  height: 2px;
  background: var(--brand-primary);
  border-radius: 1px;
}

.footer-col p,
.footer-col a {
  font-size: 14px;
  color: var(--text-on-dark-muted);
  line-height: 2;
  text-decoration: none;
  display: block;
  transition: var(--transition);
}

.footer-col a:hover {
  color: var(--brand-primary-light);
  padding-left: 4px;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: 20px 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.footer-bottom p {
  font-size: 13px;
  color: var(--text-on-dark-muted);
}

.footer-bottom-links {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
}

.footer-bottom-links a {
  font-size: 13px;
  color: var(--text-on-dark-muted);
  text-decoration: none;
  transition: var(--transition);
  position: relative;
}

.footer-bottom-links a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--brand-primary-light);
  transition: width 0.3s ease;
}

.footer-bottom-links a:hover::after {
  width: 100%;
}

.footer-bottom-links a:hover {
  color: var(--brand-primary-light);
}

/* ===== 返回顶部 ===== */
.back-to-top {
  position: fixed;
  bottom: 28px;
  right: 28px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--brand-primary), var(--brand-primary-dark));
  color: var(--text-on-brand);
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md), 0 0 0 0 rgba(255, 140, 66, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px) scale(0.9);
  transition: var(--transition);
  z-index: 999;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0) scale(1);
  animation: pulseGlow 2s ease-in-out infinite;
}

@keyframes pulseGlow {
  0%, 100% { box-shadow: var(--shadow-md), 0 0 0 0 rgba(255, 140, 66, 0.4); }
  50% { box-shadow: var(--shadow-md), 0 0 0 8px rgba(255, 140, 66, 0); }
}

.back-to-top:hover {
  transform: translateY(-3px) scale(1.06);
  box-shadow: 0 8px 24px rgba(255, 140, 66, 0.45);
  animation: none;
}

/* ===== 滚动动画 ===== */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s cubic-bezier(0.4, 0, 0.2, 1), transform 0.7s cubic-bezier(0.4, 0, 0.2, 1);
}

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

/* ===== 面包屑 ===== */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-light);
  padding: 16px 0;
  flex-wrap: wrap;
}

.breadcrumb a {
  color: var(--text-muted);
  text-decoration: none;
  transition: var(--transition);
}

.breadcrumb a:hover {
  color: var(--brand-primary-dark);
}

[data-theme="dark"] .breadcrumb a:hover {
  color: var(--brand-primary);
}

.breadcrumb .sep {
  color: var(--text-light);
}

/* ===== 表格 ===== */
.info-table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
  font-size: 14px;
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.info-table th,
.info-table td {
  padding: 12px 16px;
  text-align: left;
  border: 1px solid var(--border-color);
  transition: background-color 0.3s ease;
}

.info-table th {
  background-color: var(--bg-section);
  color: var(--text-primary);
  font-weight: 600;
  white-space: nowrap;
}

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

.info-table tr:hover td {
  background-color: rgba(255, 140, 66, 0.04);
}

[data-theme="dark"] .info-table tr:hover td {
  background-color: rgba(255, 140, 66, 0.08);
}

/* ===== 响应式 ===== */
@media (max-width: 900px) {
  .nav-links {
    display: none;
  }

  .mobile-menu-btn {
    display: flex;
  }

  .search-box input {
    width: 100px;
  }

  .hero h1 {
    font-size: 30px;
  }

  .hero p {
    font-size: 16px;
  }

  .section {
    padding: 48px 0;
  }

  .section-header h2 {
    font-size: 26px;
  }

  .slide h2 {
    font-size: 22px;
  }

  .slide p {
    font-size: 15px;
  }
}

@media (max-width: 600px) {
  .container {
    padding: 0 16px;
  }

  .search-box {
    display: none;
  }

  .hero {
    padding: 40px 0 36px;
  }

  .hero h1 {
    font-size: 26px;
  }

  .hero-actions {
    flex-direction: column;
  }

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

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

  .article-list {
    grid-template-columns: 1fr;
  }

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

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

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }

  .howto-step {
    padding-left: 52px;
  }

  .howto-step::before {
    width: 40px;
    height: 40px;
    left: -21px;
    font-size: 16px;
  }

  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 42px;
    height: 42px;
  }

  .slide {
    padding: 32px 20px;
  }

  .slide h2 {
    font-size: 20px;
  }

  .slide p {
    font-size: 14px;
  }

  .banner-slider {
    margin-top: 28px;
    border-radius: var(--radius-md);
  }

  .info-table th,
  .info-table td {
    padding: 10px 12px;
    font-size: 13px;
  }
}

@media (max-width: 400px) {
  .hero h1 {
    font-size: 23px;
  }

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

  .stat-number {
    font-size: 30px;
  }
}

/* ===== 焦点可见性 ===== */
a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--brand-primary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* ===== 文字可读性强化 ===== */
.text-strong {
  color: var(--text-primary);
  font-weight: 600;
}

.text-muted-readable {
  color: var(--text-muted);
}

.text-light-readable {
  color: var(--text-light);
}

/* ===== 滚动条美化 ===== */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

::-webkit-scrollbar-track {
  background: var(--bg-section);
}

::-webkit-scrollbar-thumb {
  background: linear-gradient(180deg, var(--brand-primary-light), var(--brand-primary));
  border-radius: 5px;
  border: 2px solid var(--bg-section);
}

::-webkit-scrollbar-thumb:hover {
  background: linear-gradient(180deg, var(--brand-primary), var(--brand-primary-dark));
}

/* ===== 选中文字 ===== */
::selection {
  background-color: rgba(255, 140, 66, 0.25);
  color: var(--text-primary);
}

/* ===== 减少动画偏好 ===== */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

  .fade-in {
    opacity: 1;
    transform: none;
  }
}