:root {
  --lemon-primary: #FFD400;
  --lemon-primary-dark: #F5C400;
  --lemon-primary-light: #FFE566;
  --lemon-accent: #FF6B35;
  --lemon-accent-dark: #E85A2A;
  --lemon-green: #4CAF50;
  --lemon-green-dark: #388E3C;
  --lemon-bg: #FFFDF5;
  --lemon-bg-alt: #FFF8E1;
  --lemon-card: #FFFFFF;
  --lemon-card-hover: #FFFDF0;
  --lemon-text: #1A1A1A;
  --lemon-text-secondary: #555555;
  --lemon-text-muted: #888888;
  --lemon-border: #F0E6C0;
  --lemon-border-light: #F5EEC8;
  --lemon-shadow: rgba(255, 212, 0, 0.15);
  --lemon-shadow-strong: rgba(255, 212, 0, 0.3);
  --lemon-glass: rgba(255, 255, 255, 0.7);
  --lemon-glass-border: rgba(255, 255, 255, 0.4);
  --lemon-gradient-1: linear-gradient(135deg, #FFD400 0%, #FFE566 50%, #FFF8E1 100%);
  --lemon-gradient-2: linear-gradient(160deg, #FFD400 0%, #FFA726 100%);
  --lemon-gradient-3: linear-gradient(135deg, #FFF8E1 0%, #FFD400 100%);
  --lemon-gradient-hero: linear-gradient(135deg, #FFD400 0%, #FFAB00 40%, #FF6B35 100%);
  --lemon-radius-sm: 8px;
  --lemon-radius: 16px;
  --lemon-radius-lg: 24px;
  --lemon-radius-xl: 32px;
  --lemon-radius-full: 50%;
  --lemon-transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --lemon-transition-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  --lemon-font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --lemon-max-width: 1200px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --lemon-bg: #0D0D0D;
    --lemon-bg-alt: #1A1A1A;
    --lemon-card: #1E1E1E;
    --lemon-card-hover: #252525;
    --lemon-text: #F0F0F0;
    --lemon-text-secondary: #B0B0B0;
    --lemon-text-muted: #777777;
    --lemon-border: #2A2A2A;
    --lemon-border-light: #333333;
    --lemon-shadow: rgba(255, 212, 0, 0.08);
    --lemon-shadow-strong: rgba(255, 212, 0, 0.15);
    --lemon-glass: rgba(30, 30, 30, 0.75);
    --lemon-glass-border: rgba(255, 255, 255, 0.08);
    --lemon-gradient-1: linear-gradient(135deg, #1A1A1A 0%, #2A2A2A 50%, #1E1E1E 100%);
    --lemon-gradient-3: linear-gradient(135deg, #1A1A1A 0%, #2A2A00 100%);
    --lemon-gradient-hero: linear-gradient(135deg, #1A1A00 0%, #2A2200 40%, #3A1A00 100%);
  }
}

*,
*::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(--lemon-font);
  font-size: 16px;
  line-height: 1.8;
  color: var(--lemon-text);
  background-color: var(--lemon-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  transition: background-color var(--lemon-transition), color var(--lemon-transition);
}

::selection {
  background: var(--lemon-primary);
  color: #1A1A1A;
}

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

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

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

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

header[role="banner"] {
  position: relative;
  background: var(--lemon-gradient-hero);
  color: #1A1A1A;
  padding: 60px 24px 50px;
  overflow: hidden;
  isolation: isolate;
}

header[role="banner"]::before {
  content: "";
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 30% 40%, rgba(255, 255, 255, 0.3) 0%, transparent 50%),
    radial-gradient(circle at 70% 60%, rgba(255, 107, 53, 0.15) 0%, transparent 50%);
  animation: lemonHeaderGlow 12s ease-in-out infinite alternate;
  z-index: -1;
}

@keyframes lemonHeaderGlow {
  0% {
    transform: translate(0, 0) scale(1);
    opacity: 0.8;
  }
  100% {
    transform: translate(3%, 2%) scale(1.05);
    opacity: 1;
  }
}

header[role="banner"]::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 60px;
  background: linear-gradient(to top, var(--lemon-bg), transparent);
  pointer-events: none;
  z-index: 1;
}

header[role="banner"] h1 {
  max-width: var(--lemon-max-width);
  margin: 0 auto 16px;
  font-size: clamp(1.5rem, 4vw, 2.4rem);
  font-weight: 800;
  line-height: 1.35;
  letter-spacing: -0.02em;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  position: relative;
  z-index: 2;
}

header[role="banner"] > p {
  max-width: var(--lemon-max-width);
  margin: 0 auto 28px;
  font-size: clamp(0.9rem, 1.8vw, 1.05rem);
  line-height: 1.9;
  color: rgba(26, 26, 26, 0.85);
  position: relative;
  z-index: 2;
}

header[role="banner"] nav {
  max-width: var(--lemon-max-width);
  margin: 0 auto;
  position: relative;
  z-index: 2;
}

header[role="banner"] nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  list-style: none;
  justify-content: center;
}

header[role="banner"] nav ul li a {
  display: inline-block;
  padding: 8px 18px;
  background: var(--lemon-glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--lemon-glass-border);
  border-radius: var(--lemon-radius-full);
  color: #1A1A1A;
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 600;
  white-space: nowrap;
  transition: all var(--lemon-transition);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
}

header[role="banner"] nav ul li a:hover,
header[role="banner"] nav ul li a:focus-visible {
  background: #1A1A1A;
  color: var(--lemon-primary);
  transform: translateY(-3px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
  border-color: #1A1A1A;
}

header[role="banner"] nav ul li a:active {
  transform: translateY(-1px);
}

main {
  max-width: var(--lemon-max-width);
  margin: 0 auto;
  padding: 0 24px 60px;
}

main > section {
  margin-bottom: 48px;
  opacity: 0;
  transform: translateY(30px);
  animation: lemonFadeInUp 0.7s ease-out forwards;
}

main > section:nth-child(1) { animation-delay: 0.05s; }
main > section:nth-child(2) { animation-delay: 0.1s; }
main > section:nth-child(3) { animation-delay: 0.15s; }
main > section:nth-child(4) { animation-delay: 0.2s; }
main > section:nth-child(5) { animation-delay: 0.25s; }
main > section:nth-child(6) { animation-delay: 0.3s; }
main > section:nth-child(7) { animation-delay: 0.35s; }
main > section:nth-child(8) { animation-delay: 0.4s; }
main > section:nth-child(9) { animation-delay: 0.45s; }
main > section:nth-child(10) { animation-delay: 0.5s; }
main > section:nth-child(11) { animation-delay: 0.55s; }
main > section:nth-child(12) { animation-delay: 0.6s; }
main > section:nth-child(13) { animation-delay: 0.65s; }
main > section:nth-child(14) { animation-delay: 0.7s; }
main > section:nth-child(15) { animation-delay: 0.75s; }
main > section:nth-child(16) { animation-delay: 0.8s; }

@keyframes lemonFadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

main > section > h2 {
  font-size: clamp(1.3rem, 3vw, 1.75rem);
  font-weight: 800;
  color: var(--lemon-text);
  margin-bottom: 24px;
  padding-bottom: 12px;
  position: relative;
  letter-spacing: -0.01em;
}

main > section > h2::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 56px;
  height: 4px;
  background: var(--lemon-gradient-2);
  border-radius: 2px;
  transition: width var(--lemon-transition-slow);
}

main > section:hover > h2::after {
  width: 100px;
}

main > section > h3 {
  font-size: clamp(1.05rem, 2.2vw, 1.25rem);
  font-weight: 700;
  color: var(--lemon-text);
  margin: 28px 0 12px;
  padding-left: 14px;
  border-left: 4px solid var(--lemon-primary);
  line-height: 1.5;
  transition: border-color var(--lemon-transition), padding-left var(--lemon-transition);
}

main > section > h3:hover {
  border-left-color: var(--lemon-accent);
  padding-left: 18px;
}

main > section > h4 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--lemon-accent);
  margin: 20px 0 8px;
}

main > section p {
  color: var(--lemon-text-secondary);
  margin-bottom: 12px;
  font-size: 0.95rem;
  line-height: 1.9;
}

main > section p a {
  color: var(--lemon-accent);
  text-decoration: none;
  font-weight: 600;
  border-bottom: 2px solid transparent;
  transition: border-color var(--lemon-transition), color var(--lemon-transition);
}

main > section p a:hover {
  color: var(--lemon-primary-dark);
  border-bottom-color: var(--lemon-primary);
}

main > section ul,
main > section ol {
  padding-left: 24px;
  margin-bottom: 16px;
}

main > section ul li,
main > section ol li {
  color: var(--lemon-text-secondary);
  margin-bottom: 8px;
  font-size: 0.95rem;
  line-height: 1.8;
  position: relative;
}

main > section ul li::marker {
  color: var(--lemon-primary);
  font-size: 1.1em;
}

main > section ol li::marker {
  color: var(--lemon-accent);
  font-weight: 700;
}

main > section article {
  background: var(--lemon-card);
  border: 1px solid var(--lemon-border);
  border-radius: var(--lemon-radius);
  padding: 24px;
  margin-bottom: 16px;
  transition: all var(--lemon-transition);
  position: relative;
  overflow: hidden;
}

main > section article::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--lemon-gradient-2);
  opacity: 0;
  transition: opacity var(--lemon-transition);
}

main > section article:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px var(--lemon-shadow-strong);
  border-color: var(--lemon-primary);
  background: var(--lemon-card-hover);
}

main > section article:hover::before {
  opacity: 1;
}

main > section article h3 {
  border-left: none;
  padding-left: 0;
  margin-top: 0;
  margin-bottom: 8px;
  font-size: 1.08rem;
}

main > section article h3:hover {
  border-left: none;
  padding-left: 0;
}

main > section article p {
  margin-bottom: 8px;
}

main > section article p:last-child {
  margin-bottom: 0;
}

main > section article p a {
  display: inline-block;
  padding: 4px 16px;
  background: var(--lemon-gradient-2);
  color: #1A1A1A;
  border-radius: var(--lemon-radius-full);
  font-size: 0.85rem;
  font-weight: 700;
  text-decoration: none;
  border-bottom: none;
  transition: all var(--lemon-transition);
}

main > section article p a:hover {
  transform: translateX(4px);
  box-shadow: 0 4px 16px var(--lemon-shadow-strong);
  color: #1A1A1A;
  border-bottom: none;
}

#brand,
#products,
#solutions,
#cases,
#news,
#articles,
#faq,
#howto,
#contact,
#sitemap,
#links,
#copyright,
#privacy,
#disclaimer,
#breadcrumb,
#search {
  background: var(--lemon-card);
  border: 1px solid var(--lemon-border);
  border-radius: var(--lemon-radius-lg);
  padding: 32px 28px;
  box-shadow: 0 4px 20px var(--lemon-shadow);
  transition: box-shadow var(--lemon-transition), border-color var(--lemon-transition);
}

#brand:hover,
#products:hover,
#solutions:hover,
#cases:hover,
#news:hover,
#articles:hover,
#faq:hover,
#howto:hover,
#contact:hover {
  box-shadow: 0 8px 32px var(--lemon-shadow-strong);
  border-color: var(--lemon-border-light);
}

#cases ul {
  list-style: none;
  padding-left: 0;
}

#cases ul li {
  position: relative;
  padding: 10px 16px 10px 40px;
  background: var(--lemon-bg-alt);
  border-radius: var(--lemon-radius-sm);
  margin-bottom: 8px;
  transition: all var(--lemon-transition);
}

#cases ul li::before {
  content: "🍋";
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 1rem;
}

#cases ul li:hover {
  background: var(--lemon-primary-light);
  transform: translateX(6px);
}

@media (prefers-color-scheme: dark) {
  #cases ul li:hover {
    background: rgba(255, 212, 0, 0.12);
  }
}

#faq h3 {
  cursor: default;
  position: relative;
  padding: 14px 18px 14px 18px;
  background: var(--lemon-bg-alt);
  border-radius: var(--lemon-radius-sm);
  border-left: 4px solid var(--lemon-primary);
  margin-bottom: 8px;
  transition: all var(--lemon-transition);
}

#faq h3:hover {
  background: var(--lemon-primary-light);
  border-left-color: var(--lemon-accent);
  padding-left: 22px;
}

@media (prefers-color-scheme: dark) {
  #faq h3:hover {
    background: rgba(255, 212, 0, 0.08);
  }
}

#faq p {
  padding: 0 18px;
  margin-bottom: 20px;
}

#howto ol {
  counter-reset: lemonStep;
  list-style: none;
  padding-left: 0;
}

#howto ol li {
  counter-increment: lemonStep;
  position: relative;
  padding: 14px 18px 14px 56px;
  background: var(--lemon-bg-alt);
  border-radius: var(--lemon-radius-sm);
  margin-bottom: 10px;
  transition: all var(--lemon-transition);
}

#howto ol li::before {
  content: counter(lemonStep);
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  width: 30px;
  height: 30px;
  background: var(--lemon-gradient-2);
  color: #1A1A1A;
  border-radius: var(--lemon-radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 0.85rem;
  transition: transform var(--lemon-transition);
}

#howto ol li:hover {
  background: var(--lemon-primary-light);
  transform: translateX(6px);
}

#howto ol li:hover::before {
  transform: translateY(-50%) scale(1.15);
}

@media (prefers-color-scheme: dark) {
  #howto ol li:hover {
    background: rgba(255, 212, 0, 0.08);
  }
}

#contact p {
  line-height: 2;
}

#contact p br {
  display: block;
  content: "";
  margin-bottom: 4px;
}

#sitemap ul,
#links ul {
  list-style: none;
  padding-left: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

#sitemap ul li a,
#links ul li a {
  display: inline-block;
  padding: 8px 18px;
  background: var(--lemon-bg-alt);
  border: 1px solid var(--lemon-border);
  border-radius: var(--lemon-radius-full);
  color: var(--lemon-text-secondary);
  text-decoration: none;
  font-size: 0.88rem;
  font-weight: 500;
  transition: all var(--lemon-transition);
}

#sitemap ul li a:hover,
#links ul li a:hover {
  background: var(--lemon-gradient-2);
  color: #1A1A1A;
  border-color: transparent;
  transform: translateY(-3px);
  box-shadow: 0 6px 20px var(--lemon-shadow-strong);
}

#breadcrumb nav ol {
  display: flex;
  align-items: center;
  gap: 8px;
  list-style: none;
  padding-left: 0;
  flex-wrap: wrap;
}

#breadcrumb nav ol li {
  font-size: 0.9rem;
  color: var(--lemon-text-muted);
}

#breadcrumb nav ol li + li::before {
  content: "›";
  margin-right: 8px;
  color: var(--lemon-primary);
  font-weight: 700;
}

#breadcrumb nav ol li a {
  color: var(--lemon-accent);
  text-decoration: none;
  font-weight: 600;
  transition: color var(--lemon-transition);
}

#breadcrumb nav ol li a:hover {
  color: var(--lemon-primary-dark);
  text-decoration: underline;
}

#search form {
  display: flex;
  gap: 12px;
  align-items: center;
  flex-wrap: wrap;
}

#search form label {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

#search form input[type="search"] {
  flex: 1;
  min-width: 200px;
  padding: 14px 20px;
  border: 2px solid var(--lemon-border);
  border-radius: var(--lemon-radius-full);
  font-size: 0.95rem;
  font-family: var(--lemon-font);
  color: var(--lemon-text);
  background: var(--lemon-bg-alt);
  outline: none;
  transition: all var(--lemon-transition);
}

#search form input[type="search"]::placeholder {
  color: var(--lemon-text-muted);
}

#search form input[type="search"]:focus {
  border-color: var(--lemon-primary);
  box-shadow: 0 0 0 4px var(--lemon-shadow);
  background: var(--lemon-card);
}

#search form button[type="submit"] {
  padding: 14px 32px;
  background: var(--lemon-gradient-2);
  color: #1A1A1A;
  border: none;
  border-radius: var(--lemon-radius-full);
  font-size: 0.95rem;
  font-weight: 700;
  font-family: var(--lemon-font);
  cursor: pointer;
  transition: all var(--lemon-transition);
  white-space: nowrap;
  box-shadow: 0 4px 16px var(--lemon-shadow-strong);
}

#search form button[type="submit"]:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 28px var(--lemon-shadow-strong);
  filter: brightness(1.05);
}

#search form button[type="submit"]:active {
  transform: translateY(-1px);
  box-shadow: 0 2px 8px var(--lemon-shadow-strong);
}

footer[role="contentinfo"] {
  background: var(--lemon-gradient-1);
  color: var(--lemon-text);
  text-align: center;
  padding: 40px 24px;
  margin-top: 20px;
  position: relative;
  overflow: hidden;
}

footer[role="contentinfo"]::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--lemon-gradient-2);
}

footer[role="contentinfo"] p {
  max-width: var(--lemon-max-width);
  margin: 0 auto 8px;
  font-size: 0.88rem;
  color: var(--lemon-text-secondary);
  line-height: 1.8;
}

footer[role="contentinfo"] p:first-child {
  font-weight: 700;
  color: var(--lemon-text);
  font-size: 0.95rem;
}

@media (prefers-color-scheme: dark) {
  footer[role="contentinfo"] {
    background: var(--lemon-gradient-1);
  }
}

@media (max-width: 768px) {
  header[role="banner"] {
    padding: 40px 16px 36px;
  }

  header[role="banner"] h1 {
    font-size: 1.35rem;
  }

  header[role="banner"] > p {
    font-size: 0.88rem;
    margin-bottom: 20px;
  }

  header[role="banner"] nav ul {
    gap: 8px;
  }

  header[role="banner"] nav ul li a {
    padding: 6px 14px;
    font-size: 0.82rem;
  }

  main {
    padding: 0 16px 40px;
  }

  main > section {
    margin-bottom: 32px;
  }

  #brand,
  #products,
  #solutions,
  #cases,
  #news,
  #articles,
  #faq,
  #howto,
  #contact,
  #sitemap,
  #links,
  #copyright,
  #privacy,
  #disclaimer,
  #breadcrumb,
  #search {
    padding: 24px 18px;
    border-radius: var(--lemon-radius);
  }

  main > section > h2 {
    font-size: 1.2rem;
    margin-bottom: 18px;
  }

  main > section > h3 {
    font-size: 1rem;
    margin-top: 22px;
  }

  main > section article {
    padding: 18px;
  }

  #search form {
    flex-direction: column;
  }

  #search form input[type="search"] {
    width: 100%;
    min-width: 0;
  }

  #search form button[type="submit"] {
    width: 100%;
    padding: 12px 24px;
  }

  footer[role="contentinfo"] {
    padding: 28px 16px;
  }

  footer[role="contentinfo"] p {
    font-size: 0.82rem;
  }
}

@media (max-width: 480px) {
  header[role="banner"] {
    padding: 32px 12px 28px;
  }

  header[role="banner"] h1 {
    font-size: 1.15rem;
  }

  header[role="banner"] nav ul li a {
    padding: 5px 12px;
    font-size: 0.78rem;
  }

  main {
    padding: 0 12px 32px;
  }

  main > section > h2 {
    font-size: 1.1rem;
  }

  main > section > h3 {
    font-size: 0.95rem;
    padding-left: 10px;
  }

  main > section p {
    font-size: 0.88rem;
  }

  #brand,
  #products,
  #solutions,
  #cases,
  #news,
  #articles,
  #faq,
  #howto,
  #contact,
  #sitemap,
  #links,
  #copyright,
  #privacy,
  #disclaimer,
  #breadcrumb,
  #search {
    padding: 18px 14px;
  }

  #howto ol li {
    padding: 12px 14px 12px 48px;
  }

  #howto ol li::before {
    width: 26px;
    height: 26px;
    font-size: 0.78rem;
    left: 10px;
  }
}

@media (min-width: 1024px) {
  main > section article {
    padding: 28px 32px;
  }

  header[role="banner"] {
    padding: 80px 40px 70px;
  }
}

@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;
  }

  main > section {
    opacity: 1;
    transform: none;
  }
}

@media print {
  header[role="banner"] {
    background: none;
    color: #000;
    padding: 20px 0;
  }

  header[role="banner"] nav {
    display: none;
  }

  main > section {
    opacity: 1;
    transform: none;
    break-inside: avoid;
    box-shadow: none;
    border: 1px solid #ccc;
  }

  footer[role="contentinfo"] {
    background: none;
    color: #000;
  }
}

a:focus-visible,
button:focus-visible,
input:focus-visible {
  outline: 3px solid var(--lemon-primary);
  outline-offset: 2px;
}

.skip-link {
  position: absolute;
  top: -100px;
  left: 16px;
  padding: 8px 16px;
  background: var(--lemon-primary);
  color: #1A1A1A;
  border-radius: var(--lemon-radius-sm);
  font-weight: 700;
  z-index: 9999;
  transition: top var(--lemon-transition);
}

.skip-link:focus {
  top: 16px;
}