:root {
  --primary: #1a5276;
  --primary-light: #2980b9;
  --primary-dark: #0e3450;
  --accent: #e74c3c;
  --accent-light: #ff6b5b;
  --accent-dark: #c0392b;
  --bg: #f0f4f8;
  --bg-alt: #e8eef4;
  --card-bg: rgba(255, 255, 255, 0.72);
  --card-border: rgba(255, 255, 255, 0.5);
  --card-shadow: 0 8px 32px rgba(26, 82, 118, 0.1);
  --text: #1a2a3a;
  --text-light: #4a6070;
  --text-lighter: #7a8fa0;
  --glass-bg: rgba(255, 255, 255, 0.25);
  --glass-border: rgba(255, 255, 255, 0.35);
  --glass-blur: 16px;
  --radius-sm: 8px;
  --radius: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.6s 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;
  --max-width: 1200px;
  --header-height: 72px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1b2a;
    --bg-alt: #132233;
    --card-bg: rgba(22, 42, 62, 0.65);
    --card-border: rgba(255, 255, 255, 0.08);
    --card-shadow: 0 8px 32px rgba(0, 0, 0, 0.35);
    --text: #e8eef4;
    --text-light: #a0b4c8;
    --text-lighter: #6a8098;
    --glass-bg: rgba(22, 42, 62, 0.45);
    --glass-border: rgba(255, 255, 255, 0.1);
    --primary: #2980b9;
    --primary-light: #3498db;
    --primary-dark: #1a5276;
  }
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height);
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font);
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.75;
  font-size: 16px;
  min-height: 100vh;
  overflow-x: hidden;
  transition: background-color var(--transition), color var(--transition);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body::before {
  content: "";
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background:
    radial-gradient(ellipse at 20% 0%, rgba(26, 82, 118, 0.08) 0%, transparent 60%),
    radial-gradient(ellipse at 80% 100%, rgba(231, 76, 60, 0.06) 0%, transparent 60%),
    radial-gradient(ellipse at 50% 50%, rgba(41, 128, 185, 0.04) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

@media (prefers-color-scheme: dark) {
  body::before {
    background:
      radial-gradient(ellipse at 20% 0%, rgba(41, 128, 185, 0.12) 0%, transparent 60%),
      radial-gradient(ellipse at 80% 100%, rgba(231, 76, 60, 0.08) 0%, transparent 60%),
      radial-gradient(ellipse at 50% 50%, rgba(26, 82, 118, 0.06) 0%, transparent 70%);
  }
}

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

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

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

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

ul {
  list-style: none;
}

h1, h2, h3, h4, h5, h6 {
  line-height: 1.3;
  font-weight: 700;
  color: var(--text);
}

h1 {
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  letter-spacing: -0.02em;
}

h2 {
  font-size: clamp(1.4rem, 3vw, 2rem);
  letter-spacing: -0.01em;
  margin-bottom: 1.25rem;
  position: relative;
  padding-bottom: 0.75rem;
}

h2::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 60px;
  height: 4px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--primary-light), var(--accent));
}

h3 {
  font-size: clamp(1.1rem, 2vw, 1.35rem);
  margin-bottom: 0.75rem;
  color: var(--primary-light);
}

@media (prefers-color-scheme: dark) {
  h3 {
    color: var(--primary-light);
  }
}

p {
  margin-bottom: 1rem;
  color: var(--text-light);
}

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

header:hover {
  box-shadow: 0 4px 24px rgba(26, 82, 118, 0.08);
}

nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

nav > a {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--text);
  letter-spacing: -0.02em;
  white-space: nowrap;
  position: relative;
  transition: color var(--transition);
}

nav > a::before {
  content: "";
  display: inline-block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-light), var(--accent));
  margin-right: 8px;
  vertical-align: middle;
  transition: transform var(--transition);
}

nav > a:hover {
  color: var(--primary-light);
}

nav > a:hover::before {
  transform: scale(1.3) rotate(90deg);
}

nav ul {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
  padding: 0.25rem 0;
}

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

nav ul li {
  flex-shrink: 0;
}

nav ul li a {
  display: block;
  padding: 0.5rem 0.85rem;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-light);
  white-space: nowrap;
  transition: all var(--transition);
  position: relative;
}

nav ul li a::after {
  content: "";
  position: absolute;
  bottom: 2px;
  left: 50%;
  transform: translateX(-50%) scaleX(0);
  width: 60%;
  height: 2px;
  border-radius: 1px;
  background: linear-gradient(90deg, var(--primary-light), var(--accent));
  transition: transform var(--transition);
}

nav ul li a:hover {
  color: var(--primary-light);
  background: rgba(41, 128, 185, 0.08);
}

nav ul li a:hover::after {
  transform: translateX(-50%) scaleX(1);
}

main {
  position: relative;
  z-index: 1;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem 3rem;
}

section {
  margin-bottom: 3rem;
  animation: fadeInUp 0.7s ease-out both;
}

section:nth-child(1) { animation-delay: 0.05s; }
section:nth-child(2) { animation-delay: 0.1s; }
section:nth-child(3) { animation-delay: 0.15s; }
section:nth-child(4) { animation-delay: 0.2s; }
section:nth-child(5) { animation-delay: 0.25s; }
section:nth-child(6) { animation-delay: 0.3s; }
section:nth-child(7) { animation-delay: 0.35s; }
section:nth-child(8) { animation-delay: 0.4s; }
section:nth-child(9) { animation-delay: 0.45s; }
section:nth-child(10) { animation-delay: 0.5s; }
section:nth-child(11) { animation-delay: 0.55s; }
section:nth-child(12) { animation-delay: 0.6s; }

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

#home {
  position: relative;
  padding: 4rem 2.5rem;
  margin-top: 2rem;
  border-radius: var(--radius-xl);
  background: linear-gradient(135deg, #1a5276 0%, #2980b9 40%, #3498db 70%, #5dade2 100%);
  color: #fff;
  overflow: hidden;
  box-shadow: 0 20px 60px rgba(26, 82, 118, 0.35);
  animation: heroFadeIn 1s ease-out both;
}

@keyframes heroFadeIn {
  from {
    opacity: 0;
    transform: translateY(40px) scale(0.98);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

#home::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -20%;
  width: 500px;
  height: 500px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.08);
  pointer-events: none;
}

#home::after {
  content: "";
  position: absolute;
  bottom: -40%;
  left: -10%;
  width: 400px;
  height: 400px;
  border-radius: 50%;
  background: rgba(231, 76, 60, 0.15);
  pointer-events: none;
}

#home h1 {
  color: #fff;
  text-shadow: 0 2px 20px rgba(0, 0, 0, 0.15);
  margin-bottom: 1.25rem;
  position: relative;
  z-index: 1;
}

#home p {
  color: rgba(255, 255, 255, 0.9);
  font-size: 1.05rem;
  max-width: 800px;
  position: relative;
  z-index: 1;
  line-height: 1.85;
}

#about,
#products,
#advantages,
#solutions,
#cases,
#news,
#howto,
#faq,
#contact,
#sitemap,
#links {
  background: var(--card-bg);
  backdrop-filter: blur(var(--glass-blur)) saturate(160%);
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(160%);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  box-shadow: var(--card-shadow);
  transition: box-shadow var(--transition), transform var(--transition), border-color var(--transition);
}

#about:hover,
#products:hover,
#advantages:hover,
#solutions:hover,
#cases:hover,
#news:hover,
#howto:hover,
#faq:hover,
#contact:hover {
  box-shadow: 0 16px 48px rgba(26, 82, 118, 0.14);
  transform: translateY(-2px);
  border-color: rgba(41, 128, 185, 0.2);
}

#about h3,
#products h3,
#advantages h3,
#solutions h3,
#cases h3,
#howto h3,
#contact h3 {
  margin-top: 1.5rem;
}

#about h3:first-of-type,
#products h3:first-of-type,
#advantages h3:first-of-type,
#solutions h3:first-of-type,
#cases h3:first-of-type,
#howto h3:first-of-type,
#contact h3:first-of-type {
  margin-top: 0;
}

#about p,
#products p,
#advantages p,
#solutions p,
#cases p,
#howto p,
#contact p {
  font-size: 0.975rem;
  line-height: 1.85;
}

#news article {
  background: var(--glass-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  margin-bottom: 1.25rem;
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
  position: relative;
  overflow: hidden;
}

#news article::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: linear-gradient(180deg, var(--primary-light), var(--accent));
  border-radius: 0 2px 2px 0;
  opacity: 0;
  transition: opacity var(--transition);
}

#news article:hover {
  transform: translateX(6px);
  box-shadow: 0 8px 24px rgba(26, 82, 118, 0.12);
  border-color: rgba(41, 128, 185, 0.25);
}

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

#news article h3 {
  margin-top: 0;
  margin-bottom: 0.5rem;
  font-size: 1.1rem;
}

#news article p:first-of-type {
  font-size: 0.85rem;
  color: var(--text-lighter);
  margin-bottom: 0.5rem;
}

#news article p:nth-of-type(2) {
  font-size: 0.95rem;
  color: var(--text-light);
  margin-bottom: 0.75rem;
}

#news article a {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--primary-light);
  transition: color var(--transition), gap var(--transition);
}

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

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

#news article a:hover::after {
  transform: translateX(4px);
}

#faq h3 {
  margin-top: 1.25rem;
  padding: 0.75rem 1rem;
  background: rgba(41, 128, 185, 0.06);
  border-radius: var(--radius-sm);
  cursor: default;
  transition: background var(--transition), color var(--transition);
  font-size: 1.05rem;
  position: relative;
  padding-left: 2.25rem;
}

#faq h3::before {
  content: "Q";
  position: absolute;
  left: 0.75rem;
  top: 50%;
  transform: translateY(-50%);
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-light), var(--accent));
  color: #fff;
  font-size: 0.7rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
}

#faq h3:hover {
  background: rgba(41, 128, 185, 0.12);
  color: var(--primary-light);
}

#faq p {
  padding: 0.5rem 1rem 0.75rem 2.25rem;
  font-size: 0.95rem;
}

#howto h3 {
  padding-left: 1.5rem;
  position: relative;
}

#howto h3::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 3px rgba(231, 76, 60, 0.2);
}

#sitemap ul,
#links ul {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 0.75rem;
}

#sitemap ul li a,
#links ul li a {
  display: block;
  padding: 0.6rem 1rem;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-light);
  text-align: center;
  transition: all var(--transition);
}

#sitemap ul li a:hover,
#links ul li a:hover {
  background: linear-gradient(135deg, var(--primary-light), var(--primary));
  color: #fff;
  border-color: transparent;
  transform: translateY(-3px);
  box-shadow: 0 6px 20px rgba(41, 128, 185, 0.3);
}

#cases p:last-of-type {
  font-style: italic;
  color: var(--text-lighter);
}

#cases h3 {
  padding-left: 1rem;
  border-left: 3px solid var(--accent);
}

#contact p {
  margin-bottom: 0.5rem;
}

#contact h3 {
  margin-top: 1.5rem;
}

footer {
  position: relative;
  z-index: 1;
  background: linear-gradient(180deg, transparent, rgba(26, 82, 118, 0.06));
  border-top: 1px solid var(--glass-border);
  padding: 3rem 1.5rem 2rem;
  margin-top: 2rem;
}

footer > section {
  max-width: var(--max-width);
  margin: 0 auto 1.5rem;
  padding: 0 0.5rem;
  animation: none;
}

footer h3 {
  font-size: 1rem;
  color: var(--text);
  margin-bottom: 0.75rem;
  position: relative;
  padding-bottom: 0.5rem;
}

footer h3::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 32px;
  height: 3px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--primary-light), var(--accent));
}

footer p {
  font-size: 0.85rem;
  color: var(--text-lighter);
  line-height: 1.8;
}

footer > p {
  max-width: var(--max-width);
  margin: 2rem auto 0;
  padding: 1.5rem 0.5rem 0;
  border-top: 1px solid var(--glass-border);
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-lighter);
}

footer > section:last-of-type {
  margin-bottom: 0;
}

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

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: rgba(41, 128, 185, 0.25);
  border-radius: 4px;
  transition: background var(--transition);
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(41, 128, 185, 0.45);
}

::selection {
  background: rgba(41, 128, 185, 0.25);
  color: var(--text);
}

@media (prefers-color-scheme: dark) {
  ::selection {
    background: rgba(52, 152, 219, 0.35);
    color: #fff;
  }
}

@media (max-width: 900px) {
  :root {
    --header-height: 64px;
  }

  nav {
    padding: 0 1rem;
  }

  nav > a {
    font-size: 1.1rem;
  }

  nav ul li a {
    padding: 0.4rem 0.65rem;
    font-size: 0.82rem;
  }

  main {
    padding: 0 1rem 2rem;
  }

  #home {
    padding: 3rem 1.75rem;
    margin-top: 1.5rem;
    border-radius: var(--radius-lg);
  }

  #about,
  #products,
  #advantages,
  #solutions,
  #cases,
  #news,
  #howto,
  #faq,
  #contact,
  #sitemap,
  #links {
    padding: 1.75rem;
    border-radius: var(--radius);
  }

  #news article {
    padding: 1.25rem;
  }
}

@media (max-width: 600px) {
  :root {
    --header-height: 56px;
  }

  body {
    font-size: 15px;
  }

  nav {
    padding: 0 0.75rem;
    gap: 0.5rem;
  }

  nav > a {
    font-size: 1rem;
  }

  nav > a::before {
    width: 8px;
    height: 8px;
    margin-right: 6px;
  }

  nav ul {
    gap: 0.1rem;
  }

  nav ul li a {
    padding: 0.35rem 0.55rem;
    font-size: 0.78rem;
  }

  main {
    padding: 0 0.75rem 1.5rem;
  }

  #home {
    padding: 2.25rem 1.25rem;
    margin-top: 1rem;
    border-radius: var(--radius);
  }

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

  #about,
  #products,
  #advantages,
  #solutions,
  #cases,
  #news,
  #howto,
  #faq,
  #contact,
  #sitemap,
  #links {
    padding: 1.25rem;
    border-radius: var(--radius-sm);
    margin-bottom: 2rem;
  }

  section {
    margin-bottom: 2rem;
  }

  h2 {
    font-size: 1.25rem;
  }

  h3 {
    font-size: 1.02rem;
  }

  #news article {
    padding: 1rem;
    margin-bottom: 1rem;
  }

  #news article:hover {
    transform: translateX(3px);
  }

  #faq h3 {
    font-size: 0.95rem;
    padding: 0.6rem 0.75rem 0.6rem 2rem;
  }

  #faq h3::before {
    left: 0.6rem;
    width: 18px;
    height: 18px;
    font-size: 0.6rem;
  }

  #faq p {
    padding-left: 2rem;
    font-size: 0.9rem;
  }

  #sitemap ul,
  #links ul {
    grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
    gap: 0.5rem;
  }

  #sitemap ul li a,
  #links ul li a {
    padding: 0.5rem 0.75rem;
    font-size: 0.82rem;
  }

  footer {
    padding: 2rem 0.75rem 1.5rem;
  }

  footer > p {
    font-size: 0.72rem;
    padding-top: 1rem;
  }
}

@media print {
  header,
  nav,
  footer,
  #home::before,
  #home::after {
    display: none;
  }

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

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

  a {
    color: #000;
    text-decoration: underline;
  }
}

@supports not (backdrop-filter: blur(16px)) {
  header {
    background: rgba(255, 255, 255, 0.95);
  }

  #about,
  #products,
  #advantages,
  #solutions,
  #cases,
  #news,
  #howto,
  #faq,
  #contact,
  #sitemap,
  #links {
    background: rgba(255, 255, 255, 0.9);
  }

  @media (prefers-color-scheme: dark) {
    header {
      background: rgba(13, 27, 42, 0.95);
    }

    #about,
    #products,
    #advantages,
    #solutions,
    #cases,
    #news,
    #howto,
    #faq,
    #contact,
    #sitemap,
    #links {
      background: rgba(19, 34, 51, 0.92);
    }
  }
}

@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;
  }

  section {
    animation: none;
  }
}