:root {
  --primary: #f97316;
  --primary-light: #fb923c;
  --primary-dark: #ea580c;
  --primary-glow: rgba(249, 115, 22, 0.35);
  --secondary: #8b5cf6;
  --secondary-light: #a78bfa;
  --accent: #06b6d4;
  --bg: #fefcf9;
  --bg-alt: #fff7ed;
  --bg-card: rgba(255, 255, 255, 0.72);
  --bg-card-hover: rgba(255, 255, 255, 0.92);
  --bg-glass: rgba(255, 255, 255, 0.55);
  --bg-glass-border: rgba(255, 255, 255, 0.7);
  --text: #1c1917;
  --text-secondary: #57534e;
  --text-muted: #a8a29e;
  --border: rgba(249, 115, 22, 0.12);
  --border-strong: rgba(249, 115, 22, 0.25);
  --shadow-sm: 0 1px 3px rgba(28, 25, 23, 0.06), 0 1px 2px rgba(28, 25, 23, 0.04);
  --shadow-md: 0 4px 16px rgba(28, 25, 23, 0.08), 0 2px 6px rgba(28, 25, 23, 0.04);
  --shadow-lg: 0 12px 40px rgba(28, 25, 23, 0.1), 0 4px 12px rgba(28, 25, 23, 0.05);
  --shadow-glow: 0 8px 32px var(--primary-glow);
  --radius-sm: 10px;
  --radius: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1080px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0c0a09;
    --bg-alt: #1c1917;
    --bg-card: rgba(41, 37, 36, 0.65);
    --bg-card-hover: rgba(41, 37, 36, 0.85);
    --bg-glass: rgba(41, 37, 36, 0.5);
    --bg-glass-border: rgba(249, 115, 22, 0.15);
    --text: #fafaf9;
    --text-secondary: #d6d3d1;
    --text-muted: #78716c;
    --border: rgba(249, 115, 22, 0.15);
    --border-strong: rgba(249, 115, 22, 0.3);
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.35);
    --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.45);
    --primary-glow: rgba(249, 115, 22, 0.25);
    --shadow-glow: 0 8px 32px var(--primary-glow);
  }
}

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

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

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.75;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  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 80% 60% at 10% 0%, rgba(249, 115, 22, 0.06), transparent 60%),
    radial-gradient(ellipse 60% 50% at 90% 20%, rgba(139, 92, 246, 0.05), transparent 60%),
    radial-gradient(ellipse 70% 50% at 50% 100%, rgba(6, 182, 212, 0.04), transparent 60%);
  pointer-events: none;
  z-index: 0;
}

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

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

a:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 3px;
  border-radius: 4px;
}

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

ul, ol {
  list-style: none;
}

header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg-glass);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid var(--bg-glass-border);
  transition: background var(--transition), box-shadow var(--transition);
}

header::after {
  content: "";
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 100%;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--primary), transparent);
  opacity: 0.3;
}

nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  gap: 4px;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
  height: 64px;
}

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

nav a {
  flex-shrink: 0;
  padding: 8px 16px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: 100px;
  position: relative;
  transition: all var(--transition);
  white-space: nowrap;
}

nav a::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 100px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  opacity: 0;
  transition: opacity var(--transition);
  z-index: -1;
}

nav a:hover {
  color: var(--primary);
  background: rgba(249, 115, 22, 0.08);
}

nav a:active {
  transform: scale(0.96);
}

main {
  position: relative;
  z-index: 1;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px 80px;
}

main > h1 {
  font-size: clamp(1.75rem, 5vw, 3rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.03em;
  margin: 48px 0 20px;
  background: linear-gradient(135deg, var(--primary-dark), var(--primary), var(--secondary));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  animation: fadeInUp 0.8s ease both;
}

main > h1 + p {
  font-size: 1.0625rem;
  color: var(--text-secondary);
  line-height: 1.85;
  max-width: 820px;
  margin-bottom: 56px;
  animation: fadeInUp 0.8s 0.1s ease both;
}

section {
  margin-bottom: 64px;
  animation: fadeInUp 0.7s ease both;
  animation-timeline: view();
  animation-range: entry 0% entry 40%;
}

section h2 {
  font-size: clamp(1.35rem, 3.5vw, 1.875rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 24px;
  padding-bottom: 14px;
  position: relative;
  color: var(--text);
}

section h2::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 56px;
  height: 3px;
  border-radius: 3px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  transition: width var(--transition-slow);
}

section:hover h2::after {
  width: 96px;
}

section h3 {
  font-size: clamp(1.05rem, 2.5vw, 1.25rem);
  font-weight: 650;
  margin: 28px 0 10px;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 8px;
}

section h3::before {
  content: "";
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  flex-shrink: 0;
}

section p {
  color: var(--text-secondary);
  font-size: 0.9375rem;
  line-height: 1.85;
  margin-bottom: 14px;
}

section ul {
  display: grid;
  gap: 10px;
  margin: 16px 0;
}

section ul li {
  position: relative;
  padding: 12px 16px 12px 44px;
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 0.9375rem;
  color: var(--text-secondary);
  transition: all var(--transition);
}

section ul li::before {
  content: "";
  position: absolute;
  left: 18px;
  top: 50%;
  transform: translateY(-50%);
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  box-shadow: 0 0 8px var(--primary-glow);
}

section ul li:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-strong);
  transform: translateX(4px);
  box-shadow: var(--shadow-sm);
}

section ol {
  counter-reset: step-counter;
  display: grid;
  gap: 12px;
  margin: 16px 0;
}

section ol li {
  counter-increment: step-counter;
  position: relative;
  padding: 16px 20px 16px 64px;
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.9375rem;
  color: var(--text-secondary);
  transition: all var(--transition);
}

section ol li::before {
  content: counter(step-counter);
  position: absolute;
  left: 16px;
  top: 50%;
  transform: translateY(-50%);
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff;
  font-size: 0.8125rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 12px var(--primary-glow);
}

section ol li:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-strong);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

article {
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 16px;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

article::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--secondary), var(--accent));
  opacity: 0;
  transition: opacity var(--transition);
}

article:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-strong);
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

article:hover::before {
  opacity: 1;
}

article h3 {
  margin-top: 0;
  font-size: 1.0625rem;
}

article h3::before {
  display: none;
}

article > p:first-of-type {
  font-size: 0.8125rem;
  color: var(--text-muted);
  margin-bottom: 8px;
}

article > p:nth-of-type(2) {
  margin-bottom: 16px;
}

article a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--primary);
  padding: 8px 18px;
  border-radius: 100px;
  background: rgba(249, 115, 22, 0.08);
  border: 1px solid rgba(249, 115, 22, 0.15);
  transition: all var(--transition);
}

article a::after {
  content: "→";
  transition: transform var(--transition);
}

article a:hover {
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: #fff;
  border-color: transparent;
  box-shadow: var(--shadow-glow);
  transform: translateY(-1px);
}

article a:hover::after {
  transform: translateX(3px);
}

section#faq h3 {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  border-radius: var(--radius) var(--radius) 0 0;
  padding: 16px 20px;
  margin: 20px 0 0;
  font-size: 1rem;
  cursor: pointer;
  transition: all var(--transition);
  position: relative;
}

section#faq h3::before {
  display: none;
}

section#faq h3::after {
  content: "+";
  position: absolute;
  right: 20px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 1.25rem;
  font-weight: 300;
  color: var(--primary);
  transition: transform var(--transition);
}

section#faq h3:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-strong);
}

section#faq h3 + p {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  border-top: none;
  border-radius: 0 0 var(--radius) var(--radius);
  padding: 16px 20px;
  margin-top: 0;
  margin-bottom: 0;
  font-size: 0.9375rem;
  line-height: 1.8;
  transition: all var(--transition);
}

section#faq h3:hover + p {
  background: var(--bg-card-hover);
  border-color: var(--border-strong);
}

section#contact p {
  padding: 10px 16px;
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  margin-bottom: 8px;
  font-size: 0.9375rem;
  transition: all var(--transition);
}

section#contact p:hover {
  border-color: var(--border-strong);
  transform: translateX(4px);
  box-shadow: var(--shadow-sm);
}

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

section#sitemap ul li,
section#links ul li {
  padding: 0;
  background: none;
  border: none;
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
}

section#sitemap ul li::before,
section#links ul li::before {
  display: none;
}

section#sitemap ul li a,
section#links ul li a {
  display: inline-block;
  padding: 10px 20px;
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  border-radius: 100px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--transition);
}

section#sitemap ul li a:hover,
section#links ul li a:hover {
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: #fff;
  border-color: transparent;
  box-shadow: var(--shadow-glow);
  transform: translateY(-2px);
}

section#legal h3 {
  margin-top: 24px;
}

section#legal p {
  font-size: 0.875rem;
}

footer {
  position: relative;
  z-index: 1;
  background: var(--bg-alt);
  border-top: 1px solid var(--border);
  padding: 40px 24px;
  text-align: center;
  transition: background var(--transition), border-color var(--transition);
}

footer p {
  font-size: 0.8125rem;
  color: var(--text-muted);
  line-height: 2;
  margin: 0;
}

footer p:first-child {
  font-weight: 600;
  color: var(--text-secondary);
  font-size: 0.875rem;
}

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

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-20px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes pulseGlow {
  0%, 100% {
    box-shadow: 0 0 0 0 var(--primary-glow);
  }
  50% {
    box-shadow: 0 0 0 8px transparent;
  }
}

@media (max-width: 768px) {
  body {
    font-size: 15px;
  }

  nav {
    padding: 0 16px;
    height: 56px;
    gap: 2px;
  }

  nav a {
    padding: 6px 12px;
    font-size: 0.8125rem;
  }

  main {
    padding: 0 16px 60px;
  }

  main > h1 {
    margin-top: 32px;
    font-size: 1.625rem;
  }

  main > h1 + p {
    font-size: 0.9375rem;
    margin-bottom: 40px;
  }

  section {
    margin-bottom: 48px;
  }

  section h2 {
    font-size: 1.25rem;
    margin-bottom: 18px;
  }

  article {
    padding: 18px;
    border-radius: var(--radius);
  }

  section ul li {
    padding: 10px 14px 10px 38px;
    font-size: 0.875rem;
  }

  section ol li {
    padding: 14px 16px 14px 56px;
    font-size: 0.875rem;
  }

  section ol li::before {
    left: 14px;
    width: 28px;
    height: 28px;
    font-size: 0.75rem;
  }

  section#faq h3 {
    padding: 14px 16px;
    font-size: 0.9375rem;
  }

  section#faq h3 + p {
    padding: 14px 16px;
    font-size: 0.875rem;
  }

  footer {
    padding: 32px 16px;
  }

  footer p {
    font-size: 0.75rem;
  }
}

@media (max-width: 480px) {
  nav {
    padding: 0 12px;
    height: 52px;
  }

  nav a {
    padding: 5px 10px;
    font-size: 0.75rem;
  }

  main {
    padding: 0 12px 48px;
  }

  main > h1 {
    font-size: 1.375rem;
  }

  section h2 {
    font-size: 1.125rem;
  }

  article {
    padding: 14px;
  }

  article h3 {
    font-size: 0.9375rem;
  }

  section#sitemap ul li a,
  section#links ul li a {
    padding: 8px 14px;
    font-size: 0.8125rem;
  }
}

@media (min-width: 1024px) {
  main {
    padding: 0 32px 100px;
  }

  nav {
    padding: 0 32px;
  }

  article {
    padding: 28px 32px;
  }

  section#articles {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
  }

  section#articles h2,
  section#articles > p {
    grid-column: 1 / -1;
  }
}

@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;
  }
}

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

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

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

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

::-webkit-scrollbar-thumb {
  background: linear-gradient(180deg, var(--primary), var(--secondary));
  border-radius: 100px;
}

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