:root {
  --primary: #1a2a6c;
  --primary-light: #2b4a9e;
  --primary-dark: #0f1a45;
  --accent: #e94560;
  --accent-light: #ff6b81;
  --accent-dark: #c23152;
  --bg: #f0f2f8;
  --bg-alt: #e4e8f2;
  --card-bg: rgba(255, 255, 255, 0.72);
  --card-border: rgba(255, 255, 255, 0.5);
  --text: #1a1a2e;
  --text-secondary: #4a4a6a;
  --text-muted: #7a7a9a;
  --shadow: 0 4px 20px rgba(26, 42, 108, 0.08);
  --shadow-hover: 0 8px 32px rgba(26, 42, 108, 0.16);
  --radius: 16px;
  --radius-sm: 10px;
  --radius-lg: 24px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --primary: #4a6cf7;
    --primary-light: #6b8aff;
    --primary-dark: #2a3a8c;
    --accent: #ff6b81;
    --accent-light: #ff8fa3;
    --accent-dark: #e94560;
    --bg: #0d1117;
    --bg-alt: #161b22;
    --card-bg: rgba(22, 27, 34, 0.78);
    --card-border: rgba(255, 255, 255, 0.08);
    --text: #e6edf3;
    --text-secondary: #b0b8c4;
    --text-muted: #7a8494;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    --shadow-hover: 0 8px 32px rgba(0, 0, 0, 0.5);
  }
}

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

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

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.75;
  min-height: 100vh;
  overflow-x: hidden;
  transition: background var(--transition), color var(--transition);
}

body::before {
  content: "";
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background:
    radial-gradient(ellipse at 20% 0%, rgba(26, 42, 108, 0.08) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 100%, rgba(233, 69, 96, 0.06) 0%, transparent 50%);
  pointer-events: none;
  z-index: 0;
}

@media (prefers-color-scheme: dark) {
  body::before {
    background:
      radial-gradient(ellipse at 20% 0%, rgba(74, 108, 247, 0.1) 0%, transparent 50%),
      radial-gradient(ellipse at 80% 100%, rgba(255, 107, 129, 0.06) 0%, transparent 50%);
  }
}

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

::-webkit-scrollbar {
  width: 8px;
}

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

::-webkit-scrollbar-thumb {
  background: var(--primary-light);
  border-radius: 4px;
}

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

header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 40%, var(--primary-light) 100%);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 2px 20px rgba(26, 42, 108, 0.25);
  transition: box-shadow var(--transition);
}

header::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
}

nav {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

nav ul {
  display: flex;
  flex-wrap: wrap;
  list-style: none;
  gap: 4px;
  padding: 10px 0;
  align-items: center;
  justify-content: center;
}

nav ul li {
  position: relative;
}

nav ul li a {
  display: block;
  padding: 8px 16px;
  color: rgba(255, 255, 255, 0.85);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  transition: all var(--transition);
  white-space: nowrap;
  letter-spacing: 0.02em;
}

nav ul li a::after {
  content: "";
  position: absolute;
  bottom: 4px;
  left: 50%;
  width: 0;
  height: 2px;
  background: var(--accent-light);
  transition: all var(--transition);
  transform: translateX(-50%);
  border-radius: 1px;
}

nav ul li a:hover {
  color: #fff;
  background: rgba(255, 255, 255, 0.1);
}

nav ul li a:hover::after {
  width: 60%;
}

main {
  position: relative;
  z-index: 1;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

section {
  margin: 48px 0;
  padding: 40px 36px;
  background: var(--card-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  transition: transform var(--transition), box-shadow var(--transition);
  animation: fadeInUp 0.7s ease both;
}

section:hover {
  box-shadow: var(--shadow-hover);
}

#home {
  margin-top: 32px;
  background: linear-gradient(135deg, rgba(26, 42, 108, 0.92) 0%, rgba(43, 74, 158, 0.88) 50%, rgba(233, 69, 96, 0.82) 100%);
  border: none;
  color: #fff;
  position: relative;
  overflow: hidden;
}

#home::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -20%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.08) 0%, transparent 70%);
  border-radius: 50%;
  animation: float 8s ease-in-out infinite;
}

#home::after {
  content: "";
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(233, 69, 96, 0.15) 0%, transparent 70%);
  border-radius: 50%;
  animation: float 10s ease-in-out infinite reverse;
}

#home h1 {
  position: relative;
  z-index: 1;
  font-size: 2.2rem;
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 24px;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, #fff 0%, rgba(255, 255, 255, 0.85) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

#home p {
  position: relative;
  z-index: 1;
  color: rgba(255, 255, 255, 0.9);
  font-size: 1.05rem;
  margin-bottom: 16px;
  max-width: 800px;
}

#home p:last-child {
  margin-bottom: 0;
}

h2 {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 24px;
  padding-bottom: 12px;
  position: relative;
  letter-spacing: -0.01em;
}

@media (prefers-color-scheme: dark) {
  h2 {
    color: var(--primary-light);
  }
}

h2::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 48px;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-light));
  border-radius: 2px;
}

h3 {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--text);
  margin: 24px 0 12px;
  padding-left: 14px;
  position: relative;
}

h3::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background: linear-gradient(180deg, var(--accent), var(--primary-light));
  border-radius: 2px;
}

p {
  color: var(--text-secondary);
  margin-bottom: 14px;
  font-size: 0.98rem;
  line-height: 1.8;
}

section ul {
  list-style: none;
  padding: 0;
}

section ul li {
  position: relative;
  padding: 8px 0 8px 24px;
  color: var(--text-secondary);
  font-size: 0.95rem;
  transition: color var(--transition);
}

section ul li::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 50%;
  width: 8px;
  height: 8px;
  background: var(--accent);
  border-radius: 50%;
  transform: translateY(-50%) scale(0.8);
  transition: transform var(--transition);
}

section ul li:hover::before {
  transform: translateY(-50%) scale(1.2);
}

section ul li:hover {
  color: var(--text);
}

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

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

article {
  background: var(--bg-alt);
  border-radius: var(--radius);
  padding: 20px 24px;
  margin-bottom: 16px;
  border: 1px solid var(--card-border);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
  animation: fadeInUp 0.6s ease both;
}

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

article h3 {
  margin-top: 0;
  font-size: 1.05rem;
}

article h3 a {
  color: var(--text);
  font-weight: 600;
}

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

article p {
  font-size: 0.9rem;
  margin-bottom: 6px;
}

article p:first-of-type {
  color: var(--text-muted);
  font-size: 0.82rem;
  font-weight: 500;
}

blockquote {
  background: var(--bg-alt);
  border-left: 4px solid var(--accent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 16px 20px;
  margin: 16px 0;
  transition: transform var(--transition), box-shadow var(--transition);
}

blockquote:hover {
  transform: translateX(4px);
  box-shadow: var(--shadow);
}

blockquote p {
  font-style: italic;
  color: var(--text-secondary);
  margin-bottom: 8px;
  font-size: 0.95rem;
}

blockquote p:last-child {
  margin-bottom: 0;
  font-style: normal;
  color: var(--text-muted);
  font-size: 0.85rem;
}

#faq h3 {
  margin-top: 28px;
  padding: 12px 16px 12px 20px;
  background: var(--bg-alt);
  border-radius: var(--radius-sm);
  border-left: 4px solid var(--primary-light);
  transition: background var(--transition), border-color var(--transition);
  cursor: default;
}

#faq h3:hover {
  background: var(--primary);
  color: #fff;
  border-color: var(--accent);
}

#faq h3:hover::before {
  background: var(--accent-light);
}

#faq h3 + p {
  padding: 12px 20px;
  background: transparent;
  border-radius: 0 0 var(--radius-sm) var(--radius-sm);
  margin-top: -4px;
}

#howto h3 {
  margin-top: 28px;
}

#contact ul li {
  padding: 10px 0 10px 24px;
  font-size: 0.95rem;
}

#contact ul li::before {
  background: var(--primary-light);
}

#sitemap ul {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 4px;
}

#sitemap ul li {
  padding: 8px 12px;
  background: var(--bg-alt);
  border-radius: var(--radius-sm);
  transition: background var(--transition), transform var(--transition);
}

#sitemap ul li::before {
  display: none;
}

#sitemap ul li:hover {
  background: var(--primary);
  transform: translateX(4px);
}

#sitemap ul li:hover a {
  color: #fff;
}

#sitemap ul li a {
  display: block;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

#links ul {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

#links ul li {
  padding: 8px 18px;
  background: var(--bg-alt);
  border-radius: 50px;
  border: 1px solid var(--card-border);
  transition: all var(--transition);
}

#links ul li::before {
  display: none;
}

#links ul li:hover {
  background: var(--primary);
  border-color: var(--primary);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(26, 42, 108, 0.2);
}

#links ul li:hover a {
  color: #fff;
}

#links ul li a {
  color: var(--text-secondary);
  font-size: 0.88rem;
  font-weight: 500;
}

footer {
  position: relative;
  z-index: 1;
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%);
  color: rgba(255, 255, 255, 0.8);
  padding: 40px 24px;
  margin-top: 64px;
  text-align: center;
}

footer p {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.88rem;
  margin-bottom: 8px;
  line-height: 1.7;
}

footer p:last-child {
  margin-bottom: 0;
}

footer p:first-child {
  font-weight: 600;
  color: rgba(255, 255, 255, 0.95);
  font-size: 0.95rem;
}

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

@keyframes float {
  0%, 100% {
    transform: translate(0, 0) scale(1);
  }
  50% {
    transform: translate(-20px, 20px) scale(1.05);
  }
}

@media (max-width: 900px) {
  html {
    font-size: 15px;
  }

  nav ul {
    gap: 2px;
    padding: 8px 0;
  }

  nav ul li a {
    padding: 6px 10px;
    font-size: 0.82rem;
  }

  main {
    padding: 0 16px;
  }

  section {
    margin: 32px 0;
    padding: 28px 20px;
    border-radius: var(--radius);
  }

  #home {
    margin-top: 24px;
    padding: 32px 20px;
  }

  #home h1 {
    font-size: 1.6rem;
  }

  #home p {
    font-size: 0.95rem;
  }

  h2 {
    font-size: 1.35rem;
  }

  h3 {
    font-size: 1.05rem;
  }

  #sitemap ul {
    grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
  }
}

@media (max-width: 600px) {
  html {
    font-size: 14px;
  }

  header {
    position: relative;
  }

  nav ul {
    flex-wrap: nowrap;
    overflow-x: auto;
    justify-content: flex-start;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    padding: 8px 0;
  }

  nav ul::-webkit-scrollbar {
    display: none;
  }

  nav ul li a {
    padding: 6px 12px;
    font-size: 0.8rem;
  }

  main {
    padding: 0 12px;
  }

  section {
    margin: 24px 0;
    padding: 24px 16px;
    border-radius: var(--radius-sm);
  }

  #home {
    margin-top: 16px;
    padding: 28px 16px;
  }

  #home h1 {
    font-size: 1.35rem;
  }

  #home p {
    font-size: 0.9rem;
  }

  h2 {
    font-size: 1.2rem;
  }

  h3 {
    font-size: 1rem;
    margin: 20px 0 10px;
  }

  p {
    font-size: 0.92rem;
  }

  article {
    padding: 16px;
  }

  article h3 {
    font-size: 0.95rem;
  }

  #sitemap ul {
    grid-template-columns: repeat(2, 1fr);
  }

  #links ul {
    flex-direction: column;
  }

  #links ul li {
    text-align: center;
  }

  footer {
    padding: 32px 16px;
  }
}

@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;
  }
}

@media print {
  header,
  footer,
  nav {
    display: none;
  }

  body {
    background: #fff;
    color: #000;
  }

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