:root {
  --primary: #1a5f7a;
  --primary-light: #2a8ba8;
  --primary-dark: #0f3d4f;
  --accent: #c9a227;
  --accent-light: #e8c547;
  --bg: #f5f7f9;
  --bg-alt: #ffffff;
  --surface: rgba(255, 255, 255, 0.72);
  --surface-solid: #ffffff;
  --border: rgba(26, 95, 122, 0.14);
  --text: #1c2833;
  --text-soft: #4a5a68;
  --text-muted: #7a8894;
  --shadow-sm: 0 2px 8px rgba(15, 61, 79, 0.06);
  --shadow-md: 0 8px 28px rgba(15, 61, 79, 0.1);
  --shadow-lg: 0 18px 48px rgba(15, 61, 79, 0.16);
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --max-width: 1180px;
  --transition: 0.32s cubic-bezier(0.22, 0.61, 0.36, 1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --primary: #4fb3d0;
    --primary-light: #6cc9e3;
    --primary-dark: #0b2b36;
    --accent: #e8c547;
    --accent-light: #f2d97a;
    --bg: #0d1418;
    --bg-alt: #131d23;
    --surface: rgba(24, 38, 46, 0.68);
    --surface-solid: #18262e;
    --border: rgba(79, 179, 208, 0.18);
    --text: #e6eef2;
    --text-soft: #b3c4cd;
    --text-muted: #7e939f;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 8px 28px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 18px 48px rgba(0, 0, 0, 0.5);
  }
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  scroll-padding-top: 84px;
}

body {
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", system-ui, -apple-system, sans-serif;
  font-size: 16px;
  line-height: 1.78;
  color: var(--text);
  background-color: var(--bg);
  background-image:
    radial-gradient(circle at 8% 4%, rgba(26, 95, 122, 0.07), transparent 42%),
    radial-gradient(circle at 92% 12%, rgba(201, 162, 39, 0.06), transparent 40%),
    radial-gradient(circle at 50% 96%, rgba(42, 139, 168, 0.05), transparent 46%);
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

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

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

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

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

ul,
ol {
  list-style: none;
}

/* ========== Header / Navigation ========== */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--surface);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
  backdrop-filter: blur(18px) saturate(160%);
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: background var(--transition), box-shadow var(--transition);
}

header nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.7rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  flex-wrap: wrap;
}

header nav > a {
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  color: var(--primary);
  position: relative;
  padding: 0.2rem 0.1rem;
  background: linear-gradient(120deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  transition: transform var(--transition);
}

header nav > a:hover {
  transform: scale(1.04);
}

header nav ul {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.15rem 0.35rem;
}

header nav ul li a {
  display: block;
  padding: 0.42rem 0.78rem;
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--text-soft);
  border-radius: 999px;
  position: relative;
  transition: color var(--transition), background var(--transition), transform var(--transition);
}

header nav ul li a::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 4px;
  width: 0;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  transform: translateX(-50%);
  transition: width var(--transition);
}

header nav ul li a:hover,
header nav ul li a:focus-visible {
  color: var(--primary);
  background: rgba(26, 95, 122, 0.08);
  transform: translateY(-1px);
}

header nav ul li a:hover::after {
  width: 55%;
}

/* ========== Main Layout ========== */
main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
}

main > nav[aria-label="面包屑导航"] {
  margin-bottom: 1.5rem;
}

main > nav[aria-label="面包屑导航"] ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.85rem;
  color: var(--text-muted);
}

main > nav[aria-label="面包屑导航"] ol li {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

main > nav[aria-label="面包屑导航"] ol li + li::before {
  content: "›";
  color: var(--text-muted);
  font-weight: 700;
}

main > nav[aria-label="面包屑导航"] ol li[aria-current="page"] {
  color: var(--text-soft);
  font-weight: 600;
}

/* ========== Sections ========== */
section {
  margin-bottom: 3.5rem;
  animation: fadeUp 0.7s cubic-bezier(0.22, 0.61, 0.36, 1) both;
}

section > h2 {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--text);
  margin-bottom: 1.6rem;
  padding-left: 1rem;
  position: relative;
  line-height: 1.35;
}

section > h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.18em;
  bottom: 0.18em;
  width: 5px;
  border-radius: 4px;
  background: linear-gradient(180deg, var(--primary), var(--accent));
}

section h3 {
  font-size: 1.14rem;
  font-weight: 700;
  color: var(--primary);
  margin: 1.6rem 0 0.6rem;
  line-height: 1.5;
  transition: color var(--transition);
}

section h3:first-of-type {
  margin-top: 0;
}

section p {
  color: var(--text-soft);
  margin-bottom: 0.85rem;
  font-size: 0.97rem;
}

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

/* ========== Hero ========== */
#hero {
  position: relative;
  padding: 3.4rem 2.8rem;
  border-radius: var(--radius-xl);
  overflow: hidden;
  color: #fff;
  background:
    radial-gradient(circle at 82% 18%, rgba(232, 197, 71, 0.32), transparent 48%),
    radial-gradient(circle at 12% 88%, rgba(108, 201, 227, 0.28), transparent 46%),
    linear-gradient(135deg, #0f3d4f 0%, #1a5f7a 46%, #2a8ba8 100%);
  box-shadow: var(--shadow-lg);
  isolation: isolate;
}

#hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
  background-size: 46px 46px;
  -webkit-mask-image: radial-gradient(circle at 50% 50%, #000 20%, transparent 78%);
  mask-image: radial-gradient(circle at 50% 50%, #000 20%, transparent 78%);
  z-index: -1;
}

#hero::after {
  content: "";
  position: absolute;
  top: -40%;
  right: -12%;
  width: 380px;
  height: 380px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.16), transparent 68%);
  pointer-events: none;
  z-index: -1;
}

#hero h1 {
  font-size: clamp(1.55rem, 4vw, 2.5rem);
  font-weight: 800;
  line-height: 1.35;
  letter-spacing: 0.01em;
  margin-bottom: 1.1rem;
  text-shadow: 0 2px 18px rgba(0, 0, 0, 0.22);
  animation: fadeUp 0.8s 0.1s cubic-bezier(0.22, 0.61, 0.36, 1) both;
}

#hero p {
  color: rgba(255, 255, 255, 0.92);
  font-size: clamp(0.95rem, 1.6vw, 1.06rem);
  line-height: 1.85;
  max-width: 62ch;
  animation: fadeUp 0.8s 0.22s cubic-bezier(0.22, 0.61, 0.36, 1) both;
}

/* ========== Cards (generic section content) ========== */
#about,
#products,
#advantages,
#solutions,
#applications,
#cases,
#testimonials,
#news,
#articles,
#knowledge,
#faq,
#howto,
#contact,
#sitemap,
#links,
#legal {
  background: var(--surface);
  -webkit-backdrop-filter: blur(14px) saturate(150%);
  backdrop-filter: blur(14px) saturate(150%);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2.2rem 2.2rem 2.4rem;
  box-shadow: var(--shadow-md);
  transition: box-shadow var(--transition), transform var(--transition), border-color var(--transition);
}

#about:hover,
#products:hover,
#advantages:hover,
#solutions:hover,
#applications:hover,
#cases:hover,
#testimonials:hover,
#news:hover,
#articles:hover,
#knowledge:hover,
#faq:hover,
#howto:hover,
#contact:hover,
#sitemap:hover,
#links:hover,
#legal:hover {
  box-shadow: var(--shadow-lg);
  border-color: rgba(26, 95, 122, 0.26);
}

/* ========== Products / Advantages / Solutions / Applications / Cases cards ========== */
#products h3,
#advantages h3,
#solutions h3,
#applications h3,
#cases h3,
#knowledge h3 {
  padding: 0.85rem 1.1rem;
  border-radius: var(--radius-sm);
  background: rgba(26, 95, 122, 0.06);
  border-left: 3px solid var(--accent);
  transition: background var(--transition), transform var(--transition), border-color var(--transition);
}

#products h3:hover,
#advantages h3:hover,
#solutions h3:hover,
#applications h3:hover,
#cases h3:hover,
#knowledge h3:hover {
  background: rgba(26, 95, 122, 0.12);
  transform: translateX(4px);
  border-left-color: var(--primary);
}

#products h3 + p,
#advantages h3 + p,
#solutions h3 + p,
#applications h3 + p,
#cases h3 + p,
#knowledge h3 + p {
  padding-left: 1.1rem;
}

/* ========== Testimonials ========== */
#testimonials blockquote {
  position: relative;
  margin: 1.2rem 0;
  padding: 1.5rem 1.6rem 1.5rem 2.6rem;
  background: linear-gradient(135deg, rgba(26, 95, 122, 0.07), rgba(201, 162, 39, 0.05));
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  transition: transform var(--transition), box-shadow var(--transition);
}

#testimonials blockquote::before {
  content: "\201C";
  position: absolute;
  left: 0.85rem;
  top: 0.2rem;
  font-size: 3rem;
  line-height: 1;
  font-family: Georgia, "Times New Roman", serif;
  color: var(--accent);
  opacity: 0.55;
}

#testimonials blockquote:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

#testimonials blockquote p {
  font-style: italic;
  color: var(--text-soft);
  margin: 0;
}

/* ========== News ========== */
#news h3 {
  position: relative;
  padding-bottom: 0.5rem;
  border-bottom: 1px dashed var(--border);
}

#news h3 + p:first-of-type {
  font-size: 0.82rem;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}

/* ========== Articles ========== */
#articles article {
  padding: 1.4rem 1.6rem;
  margin-bottom: 1.2rem;
  background: var(--surface-solid);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

#articles article:last-child {
  margin-bottom: 0;
}

#articles article:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: rgba(26, 95, 122, 0.3);
}

#articles article h3 {
  margin: 0 0 0.4rem;
  font-size: 1.08rem;
  color: var(--text);
  transition: color var(--transition);
}

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

#articles article p:first-of-type {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 0.6rem;
}

#articles article p a {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-weight: 700;
  font-size: 0.9rem;
  padding: 0.42rem 1.05rem;
  border-radius: 999px;
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  box-shadow: 0 4px 14px rgba(26, 95, 122, 0.28);
  transition: transform var(--transition), box-shadow var(--transition), filter var(--transition);
}

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

#articles article p a:hover {
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 8px 22px rgba(26, 95, 122, 0.4);
  filter: brightness(1.06);
}

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

/* ========== FAQ ========== */
#faq h3 {
  position: relative;
  padding: 0.95rem 1.1rem 0.95rem 2.4rem;
  margin: 1.1rem 0 0.55rem;
  font-size: 1rem;
  color: var(--text);
  background: var(--surface-solid);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: default;
  transition: background var(--transition), color var(--transition), border-color var(--transition), transform var(--transition);
}

#faq h3::before {
  content: "Q";
  position: absolute;
  left: 0.75rem;
  top: 50%;
  transform: translateY(-50%);
  width: 1.35rem;
  height: 1.35rem;
  display: grid;
  place-items: center;
  font-size: 0.72rem;
  font-weight: 800;
  color: #fff;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
}

#faq h3:hover {
  background: rgba(26, 95, 122, 0.08);
  color: var(--primary);
  border-color: rgba(26, 95, 122, 0.3);
  transform: translateX(3px);
}

#faq h3 + p {
  padding: 0.2rem 1.1rem 0.9rem 2.4rem;
  margin-bottom: 0.4rem;
  border-bottom: 1px dashed var(--border);
}

/* ========== HowTo ========== */
#howto h3 {
  display: inline-block;
  padding: 0.35rem 0.95rem;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--primary-dark);
  background: linear-gradient(135deg, rgba(232, 197, 71, 0.35), rgba(201, 162, 39, 0.2));
  border-radius: 999px;
  margin: 1.5rem 0 0.7rem;
}

#howto h3:first-of-type {
  margin-top: 0;
}

#howto ol,
#howto ul {
  padding-left: 1.2rem;
}

#howto p {
  padding-left: 0.2rem;
}

/* ========== Contact ========== */
#contact p {
  padding: 0.55rem 0.9rem;
  margin-bottom: 0.45rem;
  background: rgba(26, 95, 122, 0.045);
  border-radius: var(--radius-sm);
  border-left: 2px solid var(--border);
  transition: background var(--transition), border-color var(--transition), transform var(--transition);
  font-size: 0.94rem;
}

#contact p:hover {
  background: rgba(26, 95, 122, 0.1);
  border-left-color: var(--accent);
  transform: translateX(3px);
}

#contact p a {
  font-weight: 600;
}

/* ========== Sitemap & Links ========== */
#sitemap ul,
#links ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}

#sitemap ul li a,
#links ul li a {
  display: inline-block;
  padding: 0.5rem 1.05rem;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-soft);
  background: var(--surface-solid);
  border: 1px solid var(--border);
  border-radius: 999px;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition), color var(--transition), border-color var(--transition), background var(--transition);
}

#sitemap ul li a:hover,
#links ul li a:hover {
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  border-color: transparent;
  transform: translateY(-3px);
  box-shadow: 0 8px 20px rgba(26, 95, 122, 0.32);
}

/* ========== Legal ========== */
#legal h2 {
  font-size: 1.25rem;
  margin-top: 1.8rem;
}

#legal h2:first-of-type {
  margin-top: 0;
}

#legal h2::before {
  top: 0.22em;
  bottom: 0.22em;
  width: 4px;
}

#legal p {
  font-size: 0.93rem;
}

/* ========== Footer ========== */
footer {
  background: linear-gradient(160deg, var(--primary-dark) 0%, #0a2831 100%);
  color: rgba(255, 255, 255, 0.82);
  padding: 2.6rem 1.5rem 2.2rem;
  margin-top: 1rem;
  position: relative;
  overflow: hidden;
}

footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary-light), var(--accent), var(--primary-light));
}

footer p {
  max-width: var(--max-width);
  margin: 0 auto 0.6rem;
  font-size: 0.86rem;
  line-height: 1.75;
  text-align: center;
  color: rgba(255, 255, 255, 0.72);
}

footer p:first-of-type {
  font-weight: 700;
  font-size: 0.95rem;
  color: rgba(255, 255, 255, 0.92);
  letter-spacing: 0.03em;
}

footer p:last-child {
  margin-bottom: 0;
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.55);
}

/* ========== Animations ========== */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(26px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

/* Staggered scroll-reveal for direct children of sections */
section > h3,
section > p,
section > article,
section > blockquote,
section > ul,
section > ol,
#hero h1,
#hero p {
  animation: fadeUp 0.7s cubic-bezier(0.22, 0.61, 0.36, 1) both;
}

section > h3:nth-of-type(1),
section > article:nth-of-type(1) { animation-delay: 0.04s; }
section > h3:nth-of-type(2),
section > article:nth-of-type(2) { animation-delay: 0.08s; }
section > h3:nth-of-type(3),
section > article:nth-of-type(3) { animation-delay: 0.12s; }
section > h3:nth-of-type(4),
section > article:nth-of-type(4) { animation-delay: 0.16s; }
section > h3:nth-of-type(5),
section > article:nth-of-type(5) { animation-delay: 0.2s; }

/* ========== Reduced Motion ========== */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}

/* ========== Responsive ========== */
@media (max-width: 900px) {
  header nav {
    padding: 0.6rem 1rem;
    gap: 0.8rem;
  }

  header nav ul {
    gap: 0.1rem 0.2rem;
  }

  header nav ul li a {
    padding: 0.36rem 0.62rem;
    font-size: 0.85rem;
  }

  main {
    padding: 1.5rem 1rem 3rem;
  }

  #hero {
    padding: 2.4rem 1.8rem;
  }

  #about,
  #products,
  #advantages,
  #solutions,
  #applications,
  #cases,
  #testimonials,
  #news,
  #articles,
  #knowledge,
  #faq,
  #howto,
  #contact,
  #sitemap,
  #links,
  #legal {
    padding: 1.6rem 1.3rem 1.8rem;
  }

  section {
    margin-bottom: 2.4rem;
  }
}

@media (max-width: 640px) {
  html {
    scroll-padding-top: 120px;
  }

  header nav {
    flex-direction: column;
    align-items: stretch;
    gap: 0.5rem;
  }

  header nav > a {
    text-align: center;
    font-size: 1.2rem;
  }

  header nav ul {
    justify-content: center;
  }

  header nav ul li a {
    padding: 0.3rem 0.55rem;
    font-size: 0.8rem;
  }

  main {
    padding: 1.1rem 0.8rem 2.4rem;
  }

  #hero {
    padding: 1.9rem 1.2rem;
    border-radius: var(--radius-lg);
  }

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

  section > h2 {
    font-size: 1.28rem;
    padding-left: 0.85rem;
    margin-bottom: 1.1rem;
  }

  #about,
  #products,
  #advantages,
  #solutions,
  #applications,
  #cases,
  #testimonials,
  #news,
  #articles,
  #knowledge,
  #faq,
  #howto,
  #contact,
  #sitemap,
  #links,
  #legal {
    padding: 1.3rem 1rem 1.5rem;
    border-radius: var(--radius-md);
  }

  section h3 {
    font-size: 1.02rem;
  }

  #products h3,
  #advantages h3,
  #solutions h3,
  #applications h3,
  #cases h3,
  #knowledge h3 {
    padding: 0.7rem 0.85rem;
  }

  #products h3 + p,
  #advantages h3 + p,
  #solutions h3 + p,
  #applications h3 + p,
  #cases h3 + p,
  #knowledge h3 + p {
    padding-left: 0.4rem;
  }

  #articles article {
    padding: 1.1rem 1rem;
  }

  #faq h3 {
    padding: 0.8rem 0.85rem 0.8rem 2.2rem;
    font-size: 0.94rem;
  }

  #faq h3 + p {
    padding: 0.2rem 0.85rem 0.8rem 2.2rem;
  }

  #testimonials blockquote {
    padding: 1.2rem 1rem 1.2rem 2.2rem;
  }

  #contact p {
    font-size: 0.88rem;
    padding: 0.5rem 0.75rem;
  }

  footer {
    padding: 2rem 1rem 1.8rem;
  }

  footer p {
    font-size: 0.8rem;
  }
}

/* ========== High Contrast / Forced Colors ========== */
@media (forced-colors: active) {
  header,
  #hero,
  #about,
  #products,
  #advantages,
  #solutions,
  #applications,
  #cases,
  #testimonials,
  #news,
  #articles,
  #knowledge,
  #faq,
  #howto,
  #contact,
  #sitemap,
  #links,
  #legal,
  footer,
  #articles article {
    border: 1px solid CanvasText;
  }

  a {
    text-decoration: underline;
  }
}

/* ========== Print ========== */
@media print {
  header,
  footer,
  #sitemap,
  #links {
    display: none;
  }

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

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

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