:root {
  --bg: #f8f6f2;
  --surface: #ffffff;
  --surface-glass: rgba(255, 255, 255, 0.72);
  --text: #1e2b32;
  --text-secondary: #4a5c66;
  --border: #d9d2c5;
  --border-glass: rgba(255, 255, 255, 0.35);
  --primary: #2c3e50;
  --primary-light: #3e5a6e;
  --accent: #b86b4b;
  --accent-light: #d18e70;
  --accent-soft: rgba(184, 107, 75, 0.12);
  --gradient-hero: linear-gradient(135deg, #2c3e50 0%, #3e5a6e 45%, #b86b4b 100%);
  --gradient-accent: linear-gradient(135deg, #b86b4b 0%, #d18e70 100%);
  --gradient-card: linear-gradient(145deg, rgba(255,255,255,0.9) 0%, rgba(248,246,242,0.85) 100%);
  --shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
  --shadow-hover: 0 12px 32px rgba(0, 0, 0, 0.12);
  --shadow-glow: 0 0 24px rgba(184, 107, 75, 0.18);
  --radius: 12px;
  --radius-lg: 20px;
  --radius-pill: 999px;
  --header-h: 68px;
  --transition: 0.25s ease;
  --transition-slow: 0.45s cubic-bezier(0.22, 1, 0.36, 1);
  --blur: 14px;
}

[data-theme="dark"] {
  --bg: #0f161c;
  --surface: #1a242c;
  --surface-glass: rgba(26, 36, 44, 0.68);
  --text: #e5e0d8;
  --text-secondary: #aab5bc;
  --border: #2e3d46;
  --border-glass: rgba(255, 255, 255, 0.08);
  --primary: #7fa8c4;
  --primary-light: #9bbdd6;
  --accent: #d18e70;
  --accent-light: #e0a88e;
  --accent-soft: rgba(209, 142, 112, 0.16);
  --gradient-hero: linear-gradient(135deg, #16222b 0%, #1f3340 45%, #5c3a2c 100%);
  --gradient-accent: linear-gradient(135deg, #d18e70 0%, #e0a88e 100%);
  --gradient-card: linear-gradient(145deg, rgba(26,36,44,0.92) 0%, rgba(15,22,28,0.88) 100%);
  --shadow: 0 4px 16px rgba(0, 0, 0, 0.5);
  --shadow-hover: 0 12px 32px rgba(0, 0, 0, 0.65);
  --shadow-glow: 0 0 24px rgba(209, 142, 112, 0.22);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  background-color: var(--bg);
  background-image:
    radial-gradient(circle at 12% 8%, var(--accent-soft) 0%, transparent 42%),
    radial-gradient(circle at 88% 92%, rgba(44, 62, 80, 0.08) 0%, transparent 46%);
  background-attachment: fixed;
  color: var(--text);
  line-height: 1.7;
  transition: background-color var(--transition), color var(--transition);
  padding-top: var(--header-h);
  overflow-x: hidden;
}

::selection {
  background: var(--accent);
  color: #fff;
}

/* ============ 导航吸顶 ============ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-h);
  background: var(--surface-glass);
  backdrop-filter: blur(var(--blur)) saturate(180%);
  -webkit-backdrop-filter: blur(var(--blur)) saturate(180%);
  border-bottom: 1px solid var(--border-glass);
  box-shadow: var(--shadow);
  z-index: 1000;
  transition: background-color var(--transition), border-color var(--transition), box-shadow var(--transition);
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--primary);
  text-decoration: none;
  white-space: nowrap;
  transition: transform var(--transition), color var(--transition);
}

.logo:hover {
  transform: translateY(-1px);
  color: var(--accent);
}

.logo svg {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
  transition: transform var(--transition-slow);
}

.logo:hover svg {
  transform: rotate(-8deg) scale(1.06);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 20px;
  list-style: none;
}

.nav-links a {
  position: relative;
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 0.95rem;
  font-weight: 500;
  transition: color var(--transition);
  white-space: nowrap;
  padding: 4px 0;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 0;
  height: 2px;
  border-radius: var(--radius-pill);
  background: var(--gradient-accent);
  transition: width var(--transition-slow);
}

.nav-links a:hover {
  color: var(--primary);
}

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

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.search-box {
  display: flex;
  align-items: center;
  background: var(--surface-glass);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  padding: 4px 12px;
  transition: border-color var(--transition), box-shadow var(--transition), background var(--transition);
}

.search-box:focus-within {
  border-color: var(--accent);
  box-shadow: var(--shadow-glow);
}

.search-box input {
  border: none;
  background: transparent;
  padding: 6px 4px;
  font-size: 0.9rem;
  color: var(--text);
  outline: none;
  width: 130px;
  transition: width var(--transition);
}

.search-box input:focus {
  width: 170px;
}

.search-box input::placeholder {
  color: var(--text-secondary);
  opacity: 0.7;
}

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

.search-box button:hover {
  color: var(--accent);
  transform: scale(1.1);
}

.theme-toggle {
  background: var(--surface-glass);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--border);
  border-radius: 50%;
  width: 38px;
  height: 38px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-secondary);
  transition: background var(--transition), border-color var(--transition), color var(--transition), transform var(--transition);
}

.theme-toggle:hover {
  color: var(--accent);
  border-color: var(--accent);
  transform: rotate(18deg) scale(1.06);
}

.mobile-menu-btn {
  display: none;
  background: var(--surface-glass);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 6px 8px;
  cursor: pointer;
  color: var(--text);
  transition: color var(--transition), border-color var(--transition);
}

.mobile-menu-btn:hover {
  color: var(--accent);
  border-color: var(--accent);
}

/* ============ 移动端菜单 ============ */
.mobile-nav {
  display: none;
  position: fixed;
  top: var(--header-h);
  left: 0;
  width: 100%;
  background: var(--surface-glass);
  backdrop-filter: blur(var(--blur)) saturate(180%);
  -webkit-backdrop-filter: blur(var(--blur)) saturate(180%);
  border-bottom: 1px solid var(--border-glass);
  padding: 16px 20px;
  flex-direction: column;
  gap: 12px;
  z-index: 999;
  box-shadow: var(--shadow-hover);
  animation: slideDown 0.3s ease;
}

@keyframes slideDown {
  from { opacity: 0; transform: translateY(-12px); }
  to { opacity: 1; transform: translateY(0); }
}

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

.mobile-nav a {
  text-decoration: none;
  color: var(--text);
  font-size: 1rem;
  padding: 8px 0;
  border-bottom: 1px solid var(--border);
  transition: color var(--transition), padding-left var(--transition);
}

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

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

/* ============ 主容器 ============ */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ============ 面包屑 ============ */
.breadcrumb {
  padding: 16px 0 8px;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

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

.breadcrumb a:hover {
  color: var(--accent);
}

.breadcrumb span {
  margin: 0 6px;
}

/* ============ Banner轮播 ============ */
.hero {
  margin: 12px 0 32px;
  border-radius: var(--radius-lg);
  overflow: hidden;
  position: relative;
  background: var(--gradient-hero);
  box-shadow: var(--shadow-hover);
  border: 1px solid var(--border-glass);
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 85% 15%, rgba(255,255,255,0.16) 0%, transparent 38%),
    radial-gradient(circle at 10% 90%, rgba(209,142,112,0.28) 0%, transparent 44%);
  pointer-events: none;
}

.hero-slides {
  display: flex;
  transition: transform 0.55s cubic-bezier(0.22, 1, 0.36, 1);
  position: relative;
  z-index: 1;
}

.hero-slide {
  min-width: 100%;
  padding: 48px 40px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.hero-slide h1 {
  font-size: 2rem;
  color: #fff;
  line-height: 1.3;
  text-shadow: 0 2px 12px rgba(0,0,0,0.28);
  letter-spacing: 0.02em;
}

.hero-slide h1 span {
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
  filter: drop-shadow(0 2px 6px rgba(0,0,0,0.25));
}

.hero-slide p {
  font-size: 1.05rem;
  color: rgba(255, 255, 255, 0.88);
  max-width: 700px;
  text-shadow: 0 1px 6px rgba(0,0,0,0.2);
}

.hero-dots {
  position: absolute;
  bottom: 16px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 8px;
  z-index: 2;
}

.hero-dot {
  width: 10px;
  height: 10px;
  border-radius: var(--radius-pill);
  background: rgba(255, 255, 255, 0.4);
  border: none;
  cursor: pointer;
  transition: background var(--transition), width var(--transition-slow), transform var(--transition);
}

.hero-dot:hover {
  background: rgba(255, 255, 255, 0.75);
  transform: scale(1.15);
}

.hero-dot.active {
  background: var(--accent-light);
  width: 26px;
  box-shadow: 0 0 12px rgba(209, 142, 112, 0.7);
}

/* ============ 数字动画区 ============ */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin: 32px 0;
}

.stat-item {
  position: relative;
  background: var(--surface-glass);
  backdrop-filter: blur(var(--blur));
  -webkit-backdrop-filter: blur(var(--blur));
  border-radius: var(--radius-lg);
  padding: 24px 16px;
  text-align: center;
  box-shadow: var(--shadow);
  border: 1px solid var(--border-glass);
  overflow: hidden;
  transition: transform var(--transition-slow), box-shadow var(--transition-slow), border-color var(--transition);
}

.stat-item::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--gradient-accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-slow);
}

.stat-item:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-hover);
  border-color: var(--accent);
}

.stat-item:hover::before {
  transform: scaleX(1);
}

.stat-number {
  font-size: 2rem;
  font-weight: 700;
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
  display: block;
  line-height: 1.2;
}

.stat-label {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-top: 4px;
}

/* ============ 通用章节 ============ */
section {
  margin: 48px 0;
  scroll-margin-top: calc(var(--header-h) + 16px);
}

.section-title {
  position: relative;
  font-size: 1.6rem;
  color: var(--primary);
  margin-bottom: 8px;
  padding-left: 18px;
  line-height: 1.35;
}

.section-title::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.18em;
  bottom: 0.18em;
  width: 5px;
  border-radius: var(--radius-pill);
  background: var(--gradient-accent);
  box-shadow: 0 0 12px rgba(184, 107, 75, 0.4);
}

.section-sub {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: 24px;
  padding-left: 23px;
}

/* ============ 卡片网格 ============ */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
}

.card {
  position: relative;
  background: var(--gradient-card);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: transform var(--transition-slow), box-shadow var(--transition-slow), border-color var(--transition);
}

.card::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  padding: 1px;
  background: linear-gradient(135deg, var(--accent-light), transparent 45%, transparent 60%, var(--primary-light));
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  opacity: 0;
  transition: opacity var(--transition-slow);
  pointer-events: none;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-hover);
  border-color: transparent;
}

.card:hover::after {
  opacity: 1;
}

.card h3 {
  font-size: 1.15rem;
  color: var(--primary);
  margin-bottom: 10px;
  transition: color var(--transition);
}

.card:hover h3 {
  color: var(--accent);
}

.card p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.card p a {
  color: var(--accent);
  text-decoration: none;
  transition: color var(--transition);
}

.card p a:hover {
  color: var(--accent-light);
  text-decoration: underline;
}

/* ============ 文章列表 ============ */
.article-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
}

.article-item {
  position: relative;
  background: var(--gradient-card);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 20px;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  gap: 8px;
  overflow: hidden;
  transition: transform var(--transition-slow), box-shadow var(--transition-slow), border-color var(--transition);
}

.article-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--gradient-accent);
  transform: scaleY(0);
  transform-origin: top;
  transition: transform var(--transition-slow);
}

.article-item:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  border-color: var(--accent);
}

.article-item:hover::before {
  transform: scaleY(1);
}

.article-item h3 {
  font-size: 1.05rem;
  color: var(--primary);
  transition: color var(--transition);
}

.article-item:hover h3 {
  color: var(--accent);
}

.article-meta {
  font-size: 0.8rem;
  color: var(--text-secondary);
  display: flex;
  gap: 12px;
}

.article-meta span {
  position: relative;
  padding-left: 12px;
}

.article-meta span::before {
  content: "·";
  position: absolute;
  left: 0;
}

.article-item p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  flex: 1;
}

.read-more {
  font-size: 0.85rem;
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
  align-self: flex-start;
  transition: color var(--transition), transform var(--transition);
}

.read-more:hover {
  color: var(--accent-light);
  text-decoration: underline;
  transform: translateX(3px);
}

/* ============ FAQ ============ */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.faq-item {
  background: var(--surface-glass);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.faq-item.open {
  border-color: var(--accent);
  box-shadow: var(--shadow-glow);
}

.faq-question {
  width: 100%;
  text-align: left;
  padding: 16px 20px;
  background: none;
  border: none;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  font-family: inherit;
  transition: background var(--transition), color var(--transition);
}

.faq-question:hover {
  background: var(--accent-soft);
  color: var(--accent);
}

.faq-question svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  transition: transform 0.35s cubic-bezier(0.22, 1, 0.36, 1), color var(--transition);
}

.faq-item.open .faq-question svg {
  transform: rotate(180deg);
  color: var(--accent);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s cubic-bezier(0.22, 1, 0.36, 1), padding 0.4s ease;
  padding: 0 20px;
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.8;
}

.faq-item.open .faq-answer {
  max-height: 800px;
  padding: 0 20px 20px;
}

/* ============ HowTo ============ */
.howto-steps {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.step {
  display: flex;
  gap: 16px;
  background: var(--gradient-card);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 20px;
  box-shadow: var(--shadow);
  transition: transform var(--transition-slow), box-shadow var(--transition-slow), border-color var(--transition);
}

.step:hover {
  transform: translateX(6px);
  box-shadow: var(--shadow-hover);
  border-color: var(--accent);
}

.step-num {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--gradient-accent);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  flex-shrink: 0;
  box-shadow: 0 4px 12px rgba(184, 107, 75, 0.35);
  transition: transform var(--transition-slow);
}

.step:hover .step-num {
  transform: scale(1.1) rotate(-6deg);
}

.step-content h4 {
  font-size: 1rem;
  color: var(--primary);
  margin-bottom: 4px;
}

.step-content p {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

/* ============ 团队/EEAT ============ */
.team-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
}

.team-member {
  background: var(--gradient-card);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 20px;
  text-align: center;
  box-shadow: var(--shadow);
  transition: transform var(--transition-slow), box-shadow var(--transition-slow), border-color var(--transition);
}

.team-member:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
  border-color: var(--accent);
}

.team-avatar {
  width: 72px;
  height: 72px;
  border-radius: 50%;
  background: var(--accent-soft);
  margin: 0 auto 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 2px solid var(--accent);
  transition: transform var(--transition-slow), box-shadow var(--transition-slow);
}

.team-member:hover .team-avatar {
  transform: scale(1.08);
  box-shadow: var(--shadow-glow);
}

.team-member h4 {
  font-size: 1rem;
  color: var(--primary);
}

.team-member p {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* ============ 联系信息 ============ */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 20px;
}

.contact-item {
  background: var(--surface-glass);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 20px;
  box-shadow: var(--shadow);
  transition: transform var(--transition-slow), box-shadow var(--transition-slow), border-color var(--transition);
}

.contact-item:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  border-color: var(--accent);
}

.contact-item h4 {
  font-size: 0.95rem;
  color: var(--primary);
  margin-bottom: 6px;
}

.contact-item p {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

/* ============ 页脚 ============ */
.site-footer {
  position: relative;
  background: var(--surface-glass);
  backdrop-filter: blur(var(--blur)) saturate(160%);
  -webkit-backdrop-filter: blur(var(--blur)) saturate(160%);
  border-top: 1px solid var(--border-glass);
  padding: 40px 0 24px;
  margin-top: 48px;
}

.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--gradient-accent);
  opacity: 0.85;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 28px;
  margin-bottom: 28px;
}

.footer-col h4 {
  font-size: 0.95rem;
  color: var(--primary);
  margin-bottom: 12px;
}

.footer-col ul {
  list-style: none;
}

.footer-col li {
  margin-bottom: 8px;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.footer-col a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.85rem;
  transition: color var(--transition), padding-left var(--transition);
}

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

.footer-bottom {
  border-top: 1px solid var(--border-glass);
  padding-top: 20px;
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.footer-bottom p {
  margin-bottom: 4px;
}

/* ============ 返回顶部 ============ */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--gradient-accent);
  color: #fff;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 6px 20px rgba(184, 107, 75, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 0.3s, visibility 0.3s, transform 0.3s, box-shadow 0.3s;
  z-index: 900;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  transform: translateY(-4px) scale(1.06);
  box-shadow: 0 10px 28px rgba(184, 107, 75, 0.55);
}

/* ============ 滚动动画 ============ */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1), transform 0.7s cubic-bezier(0.22, 1, 0.36, 1);
  will-change: opacity, transform;
}

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

/* ============ 图片懒加载占位 ============ */
.lazy-img {
  background: var(--bg);
  border-radius: 8px;
}

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

/* ============ 响应式 ============ */
@media (max-width: 900px) {
  .nav-links {
    display: none;
  }
  .mobile-menu-btn {
    display: flex;
  }
  .search-box {
    display: none;
  }
  .stats {
    grid-template-columns: repeat(2, 1fr);
  }
  .hero-slide {
    padding: 32px 24px;
  }
  .hero-slide h1 {
    font-size: 1.5rem;
  }
  .hero-slide p {
    font-size: 0.98rem;
  }
}

@media (max-width: 600px) {
  html {
    font-size: 15px;
  }
  .stats {
    grid-template-columns: 1fr 1fr;
    gap: 12px;
  }
  .stat-item {
    padding: 18px 10px;
  }
  .stat-number {
    font-size: 1.6rem;
  }
  .hero {
    border-radius: var(--radius);
  }
  .hero-slide {
    padding: 24px 16px;
  }
  .hero-slide h1 {
    font-size: 1.3rem;
  }
  .section-title {
    font-size: 1.3rem;
  }
  .card,
  .article-item,
  .step,
  .team-member,
  .contact-item {
    padding: 18px;
  }
  .step {
    gap: 12px;
  }
  .step:hover {
    transform: translateY(-3px);
  }
  .back-to-top {
    bottom: 16px;
    right: 16px;
    width: 40px;
    height: 40px;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 20px;
  }
}

@media (max-width: 380px) {
  .stats {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
}

/* ============ 辅助类 ============ */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

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

.mt-2 { margin-top: 8px; }
.mt-4 { margin-top: 16px; }
.mb-4 { margin-bottom: 16px; }

/* ============ 无障碍与动效偏好 ============ */
@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;
  }
}

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

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

::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: var(--radius-pill);
  border: 2px solid var(--bg);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--accent);
}