:root {
  --primary: #c0392b;
  --primary-dark: #8e1b12;
  --primary-light: #e74c3c;
  --primary-glow: rgba(192, 57, 43, 0.35);
  --accent: #8e44ad;
  --accent-dark: #5b2c6f;
  --bg: #f5f6fa;
  --bg-alt: #ffffff;
  --bg-elevated: #ffffff;
  --bg-glass: rgba(255, 255, 255, 0.72);
  --bg-glass-border: rgba(255, 255, 255, 0.55);
  --bg-subtle: #fdf3f2;
  --bg-muted: #fafafa;
  --text: #2c3e50;
  --text-strong: #1a252f;
  --text-muted: #4a5568;
  --text-light: #7f8c8d;
  --text-faint: #95a5a6;
  --border: #eeeeee;
  --border-strong: #e2e8f0;
  --footer-bg: #1a252f;
  --footer-text: #bdc3c7;
  --shadow-sm: 0 2px 12px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 26px rgba(192, 57, 43, 0.13);
  --shadow-glow: 0 6px 18px rgba(192, 57, 43, 0.4);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 14px;
  --radius-pill: 20px;
  --transition: 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
  --transition-slow: 0.7s cubic-bezier(0.25, 0.8, 0.25, 1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --primary: #e74c3c;
    --primary-dark: #c0392b;
    --primary-light: #ff6b5a;
    --primary-glow: rgba(231, 76, 60, 0.4);
    --accent: #a569bd;
    --accent-dark: #8e44ad;
    --bg: #0f1419;
    --bg-alt: #1a1f2e;
    --bg-elevated: #1e2433;
    --bg-glass: rgba(30, 36, 51, 0.78);
    --bg-glass-border: rgba(255, 255, 255, 0.08);
    --bg-subtle: #2a1f1e;
    --bg-muted: #1a1f2e;
    --text: #e2e8f0;
    --text-strong: #f5f6fa;
    --text-muted: #b0bec5;
    --text-light: #8b9bb0;
    --text-faint: #6b7a8f;
    --border: #2a3142;
    --border-strong: #3a4255;
    --footer-bg: #0a0e14;
    --footer-text: #8b9bb0;
    --shadow-sm: 0 2px 12px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.45);
    --shadow-lg: 0 10px 26px rgba(231, 76, 60, 0.2);
    --shadow-glow: 0 6px 18px rgba(231, 76, 60, 0.45);
  }
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: "Microsoft YaHei", "PingFang SC", "Hiragino Sans GB", "Helvetica Neue", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.8;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  transition: background 0.4s ease, color 0.4s ease;
}

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

a:hover {
  text-decoration: underline;
  color: var(--primary-light);
}

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

::selection {
  background: var(--primary);
  color: #ffffff;
}

::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

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

::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border-radius: 5px;
}

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

header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--bg-glass);
  -webkit-backdrop-filter: blur(18px) saturate(180%);
  backdrop-filter: blur(18px) saturate(180%);
  box-shadow: var(--shadow-sm);
  border-bottom: 1px solid var(--bg-glass-border);
  transition: background 0.4s ease, box-shadow 0.4s ease;
}

.nav-wrap {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 20px;
  gap: 16px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 22px;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
  flex-shrink: 0;
  transition: transform var(--transition);
}

.logo:hover {
  text-decoration: none;
  transform: scale(1.03);
}

.logo svg {
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  filter: drop-shadow(0 4px 10px var(--primary-glow));
  transition: filter var(--transition), transform var(--transition);
}

.logo:hover svg {
  filter: drop-shadow(0 6px 16px var(--primary-glow));
  transform: rotate(-4deg);
}

nav ul {
  display: flex;
  list-style: none;
  gap: 22px;
  align-items: center;
}

nav a {
  color: var(--text);
  font-size: 15px;
  font-weight: 500;
  text-decoration: none;
  position: relative;
  padding: 4px 0;
  transition: color var(--transition);
}

nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: 2px;
  transition: width var(--transition);
}

nav a:hover {
  color: var(--primary);
  text-decoration: none;
}

nav a:hover::after {
  width: 100%;
}

.search-box {
  display: flex;
  align-items: center;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-pill);
  overflow: hidden;
  background: var(--bg-elevated);
  transition: border-color var(--transition), box-shadow var(--transition);
  flex-shrink: 0;
}

.search-box:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

.search-box input {
  border: none;
  outline: none;
  padding: 7px 14px;
  font-size: 14px;
  width: 150px;
  background: transparent;
  color: var(--text);
  font-family: inherit;
}

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

.search-box button {
  border: none;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #ffffff;
  padding: 7px 16px;
  cursor: pointer;
  font-size: 14px;
  font-family: inherit;
  font-weight: 500;
  transition: background var(--transition), transform var(--transition);
}

.search-box button:hover {
  background: linear-gradient(135deg, var(--primary-light), var(--primary));
}

.search-box button:active {
  transform: scale(0.96);
}

.menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 26px;
  cursor: pointer;
  color: var(--primary);
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  transition: background var(--transition), transform var(--transition);
}

.menu-toggle:hover {
  background: var(--bg-subtle);
}

.menu-toggle:active {
  transform: scale(0.92);
}

.banner {
  position: relative;
  max-width: 1200px;
  margin: 24px auto;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  background: #1a1a2e;
}

.slides {
  position: relative;
  height: 360px;
}

.slide {
  position: absolute;
  inset: 0;
  opacity: 0;
  transition: opacity 0.8s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: #ffffff;
  padding: 40px;
}

.slide.active {
  opacity: 1;
}

.slide h2 {
  font-size: 34px;
  margin-bottom: 16px;
  color: #ffffff;
  border-left: none;
  padding-left: 0;
  text-shadow: 0 2px 20px rgba(0, 0, 0, 0.25);
  animation: slideUp 0.8s ease both;
}

.slide p {
  font-size: 17px;
  max-width: 680px;
  margin: 0 auto;
  opacity: 0.92;
  color: rgba(255, 255, 255, 0.92);
  text-align: center;
  animation: slideUp 0.8s 0.15s ease both;
}

.slide-1 {
  background: linear-gradient(135deg, #c0392b 0%, #8e1b12 50%, #5b0f0a 100%);
}

.slide-2 {
  background: linear-gradient(135deg, #2c3e50 0%, #1a252f 50%, #0f1419 100%);
}

.slide-3 {
  background: linear-gradient(135deg, #8e44ad 0%, #5b2c6f 50%, #3d1a4d 100%);
}

.slide-1::before,
.slide-2::before,
.slide-3::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 30% 50%, rgba(255, 255, 255, 0.12), transparent 60%);
  pointer-events: none;
}

.dots {
  position: absolute;
  bottom: 16px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 10px;
  z-index: 2;
}

.dots span {
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.5);
  cursor: pointer;
  transition: background var(--transition), transform var(--transition), width var(--transition);
}

.dots span:hover {
  background: rgba(255, 255, 255, 0.8);
  transform: scale(1.2);
}

.dots span.active {
  background: #ffffff;
  width: 28px;
  border-radius: 6px;
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px 60px;
}

section {
  background: var(--bg-elevated);
  border-radius: var(--radius-md);
  padding: 36px;
  margin-bottom: 28px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
  transition: background 0.4s ease, box-shadow 0.4s ease, border-color 0.4s ease;
}

h1 {
  font-size: 30px;
  color: var(--text-strong);
  margin-bottom: 18px;
  line-height: 1.4;
  letter-spacing: -0.3px;
}

h2 {
  font-size: 24px;
  color: var(--primary);
  margin: 0 0 20px;
  padding-left: 14px;
  border-left: 5px solid var(--primary);
  line-height: 1.4;
}

h3 {
  font-size: 19px;
  color: var(--text);
  margin: 22px 0 12px;
  line-height: 1.5;
}

h4 {
  font-size: 16px;
  color: var(--text-muted);
  margin: 16px 0 10px;
  line-height: 1.5;
}

p {
  margin-bottom: 14px;
  color: var(--text-muted);
  text-align: justify;
  word-break: break-word;
}

.breadcrumb {
  max-width: 1200px;
  margin: 16px auto 0;
  padding: 0 20px;
  font-size: 14px;
  color: var(--text-light);
}

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

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

.intro {
  font-size: 17px;
  background: var(--bg-subtle);
  border-left: 4px solid var(--primary);
  padding: 18px 22px;
  border-radius: var(--radius-sm);
  margin-bottom: 20px;
  transition: background 0.4s ease;
}

.intro p {
  color: var(--text);
  margin-bottom: 0;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 22px;
  margin-top: 18px;
}

.card {
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 22px;
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition), background 0.4s ease;
  background: var(--bg-elevated);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-light);
}

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

.card h3 {
  margin-top: 0;
  color: var(--primary);
}

.card p:last-child {
  margin-bottom: 0;
}

.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 20px;
  text-align: center;
  margin-top: 20px;
}

.stat-num {
  font-size: 36px;
  font-weight: 700;
  color: var(--primary);
  line-height: 1.2;
  font-variant-numeric: tabular-nums;
}

.stat-label {
  color: var(--text-light);
  font-size: 15px;
}

article {
  border-bottom: 1px dashed var(--border-strong);
  padding: 20px 0;
  transition: border-color 0.4s ease;
}

article:last-child {
  border-bottom: none;
}

article h3 {
  margin-top: 0;
  transition: color var(--transition);
}

article:hover h3 {
  color: var(--primary);
}

.meta {
  font-size: 13px;
  color: var(--text-faint);
  margin-bottom: 10px;
}

.meta span {
  margin-right: 16px;
}

.faq-item {
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  margin-bottom: 12px;
  overflow: hidden;
  transition: border-color var(--transition), box-shadow var(--transition), background 0.4s ease;
}

.faq-item:hover {
  border-color: var(--primary-light);
  box-shadow: 0 4px 14px var(--primary-glow);
}

.faq-item.open {
  border-color: var(--primary);
}

.faq-q {
  background: var(--bg-muted);
  padding: 16px 20px;
  cursor: pointer;
  font-weight: 600;
  color: var(--text);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  user-select: none;
  transition: background var(--transition), color var(--transition);
}

.faq-q:hover {
  background: var(--bg-subtle);
  color: var(--primary);
}

.faq-q::after {
  content: "+";
  font-size: 22px;
  color: var(--primary);
  transition: transform var(--transition);
  flex-shrink: 0;
  line-height: 1;
}

.faq-item.open .faq-q::after {
  content: "−";
  transform: rotate(180deg);
}

.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.4s ease;
  padding: 0 20px;
  color: var(--text-muted);
}

.faq-item.open .faq-a {
  max-height: 500px;
  padding: 16px 20px;
}

.steps {
  counter-reset: step;
  list-style: none;
}

.steps li {
  position: relative;
  padding: 16px 0 16px 56px;
  border-bottom: 1px dashed var(--border);
  color: var(--text-muted);
  transition: background var(--transition);
}

.steps li:hover {
  background: var(--bg-subtle);
  border-radius: var(--radius-sm);
}

.steps li:last-child {
  border-bottom: none;
}

.steps li::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 0;
  top: 14px;
  width: 38px;
  height: 38px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #ffffff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  box-shadow: 0 4px 12px var(--primary-glow);
  transition: transform var(--transition), box-shadow var(--transition);
}

.steps li:hover::before {
  transform: scale(1.1);
  box-shadow: 0 6px 18px var(--primary-glow);
}

.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 18px;
  margin-top: 18px;
}

.contact-item {
  background: var(--bg-subtle);
  border-radius: 10px;
  padding: 18px;
  transition: transform var(--transition), box-shadow var(--transition), background 0.4s ease;
}

.contact-item:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-sm);
}

.contact-item strong {
  color: var(--primary);
  display: block;
  margin-bottom: 6px;
}

.tag {
  display: inline-block;
  background: var(--bg-subtle);
  color: var(--primary);
  border-radius: var(--radius-lg);
  padding: 3px 12px;
  font-size: 13px;
  margin: 3px 5px 3px 0;
  transition: background var(--transition), color var(--transition), transform var(--transition);
}

.tag:hover {
  background: var(--primary);
  color: #ffffff;
  transform: translateY(-2px);
}

.toc {
  background: var(--bg-muted);
  border-radius: 10px;
  padding: 18px 24px;
  margin-bottom: 22px;
  transition: background 0.4s ease;
}

.toc a {
  margin-right: 18px;
  font-size: 14px;
  display: inline-block;
  transition: color var(--transition), transform var(--transition);
}

.toc a:hover {
  transform: translateY(-2px);
}

footer {
  background: var(--footer-bg);
  color: var(--footer-text);
  padding: 44px 20px 20px;
  margin-top: 20px;
  transition: background 0.4s ease;
}

.footer-wrap {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 30px;
}

footer h4 {
  color: #ffffff;
  margin-bottom: 14px;
  font-size: 16px;
}

footer ul {
  list-style: none;
}

footer li {
  margin-bottom: 8px;
  font-size: 14px;
}

footer a {
  color: var(--footer-text);
  transition: color var(--transition), padding-left var(--transition);
  display: inline-block;
}

footer a:hover {
  color: #ffffff;
  text-decoration: none;
  padding-left: 4px;
}

.copyright {
  max-width: 1200px;
  margin: 30px auto 0;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  text-align: center;
  font-size: 13px;
  color: var(--text-faint);
}

.copyright p {
  color: var(--text-faint);
  text-align: center;
  margin-bottom: 6px;
}

#backTop {
  position: fixed;
  right: 26px;
  bottom: 26px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #ffffff;
  border: none;
  font-size: 22px;
  cursor: pointer;
  display: none;
  z-index: 999;
  box-shadow: var(--shadow-glow);
  transition: transform var(--transition), box-shadow var(--transition), opacity var(--transition);
  align-items: center;
  justify-content: center;
  line-height: 1;
}

#backTop:hover {
  transform: translateY(-4px) scale(1.08);
  box-shadow: 0 10px 28px var(--primary-glow);
}

#backTop:active {
  transform: scale(0.94);
}

.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity var(--transition-slow), transform var(--transition-slow);
  will-change: opacity, transform;
}

.reveal.visible {
  opacity: 1;
  transform: none;
}

@media (max-width: 1024px) {
  .slides {
    height: 320px;
  }
  .slide h2 {
    font-size: 28px;
  }
  nav ul {
    gap: 16px;
  }
  .search-box input {
    width: 120px;
  }
}

@media (max-width: 820px) {
  html {
    scroll-padding-top: 70px;
  }

  nav {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--bg-glass);
    -webkit-backdrop-filter: blur(18px) saturate(180%);
    backdrop-filter: blur(18px) saturate(180%);
    flex-direction: column;
    padding: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease, padding 0.4s ease;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
    border-bottom: 1px solid var(--bg-glass-border);
  }

  nav.open {
    max-height: 420px;
    padding: 14px 0;
  }

  nav ul {
    flex-direction: column;
    gap: 0;
    width: 100%;
  }

  nav li {
    padding: 12px 24px;
    border-bottom: 1px solid var(--border);
    width: 100%;
  }

  nav li:last-child {
    border-bottom: none;
  }

  nav a {
    display: block;
  }

  nav a::after {
    display: none;
  }

  .menu-toggle {
    display: block;
  }

  .search-box {
    display: none;
  }

  .slides {
    height: 300px;
  }

  .slide h2 {
    font-size: 24px;
  }

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

  section {
    padding: 24px 18px;
    border-radius: var(--radius-sm);
  }

  h1 {
    font-size: 23px;
  }

  h2 {
    font-size: 20px;
  }

  h3 {
    font-size: 17px;
  }

  .grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .stats {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }

  .stat-num {
    font-size: 28px;
  }

  .footer-wrap {
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }

  #backTop {
    right: 16px;
    bottom: 16px;
    width: 42px;
    height: 42px;
    font-size: 19px;
  }

  .toc a {
    display: block;
    margin: 6px 0;
  }
}

@media (max-width: 480px) {
  .nav-wrap {
    padding: 10px 14px;
  }

  .logo {
    font-size: 18px;
  }

  .logo svg {
    width: 34px;
    height: 34px;
  }

  .slides {
    height: 260px;
  }

  .slide {
    padding: 24px 18px;
  }

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

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

  main {
    padding: 0 12px 40px;
  }

  section {
    padding: 20px 14px;
  }

  h1 {
    font-size: 20px;
  }

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

  .stat-num {
    font-size: 24px;
  }

  .stat-label {
    font-size: 13px;
  }

  .footer-wrap {
    grid-template-columns: 1fr;
    gap: 20px;
  }

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

@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;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}

@media print {
  header,
  .banner,
  #backTop,
  footer {
    display: none;
  }

  body {
    background: #ffffff;
    color: #000000;
  }

  section {
    box-shadow: none;
    border: 1px solid #cccccc;
    page-break-inside: avoid;
  }
}