:root {
  --primary: #1a73e8;
  --primary-dark: #1557b0;
  --primary-light: #4a90e8;
  --secondary: #0f9d58;
  --accent: #db4437;
  --gradient-1: linear-gradient(135deg, #1a73e8 0%, #6c5ce7 100%);
  --gradient-2: linear-gradient(135deg, #0f9d58 0%, #00b894 100%);
  --gradient-3: linear-gradient(135deg, #db4437 0%, #e17055 100%);
  --gradient-hero: linear-gradient(135deg, #1a73e8 0%, #6c5ce7 50%, #a29bfe 100%);
  --bg: #f5f7fb;
  --bg-card: #ffffff;
  --bg-glass: rgba(255, 255, 255, 0.72);
  --bg-glass-border: rgba(255, 255, 255, 0.4);
  --text: #1f2937;
  --text-muted: #5f6b7a;
  --text-light: #8a94a6;
  --border: #e3e8f0;
  --shadow-sm: 0 2px 8px rgba(26, 115, 232, 0.06);
  --shadow-md: 0 8px 24px rgba(26, 115, 232, 0.1);
  --shadow-lg: 0 16px 48px rgba(26, 115, 232, 0.16);
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-full: 999px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --header-h: 68px;
  --max-w: 1200px;
}

[data-theme="dark"] {
  --bg: #0f1420;
  --bg-card: #1a2233;
  --bg-glass: rgba(26, 34, 51, 0.72);
  --bg-glass-border: rgba(255, 255, 255, 0.08);
  --text: #e8edf5;
  --text-muted: #a3aec2;
  --text-light: #6d7a90;
  --border: #2a3448;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.5);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 16px);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.75;
  color: var(--text);
  background: var(--bg);
  transition: background var(--transition), color var(--transition);
  overflow-x: hidden;
}

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

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

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

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

/* ============ Header ============ */
#site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--bg-glass);
  -webkit-backdrop-filter: blur(18px) saturate(180%);
  backdrop-filter: blur(18px) saturate(180%);
  border-bottom: 1px solid var(--bg-glass-border);
  box-shadow: var(--shadow-sm);
  transition: background var(--transition), box-shadow var(--transition);
}

.header-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
  height: var(--header-h);
  display: flex;
  align-items: center;
  gap: 20px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
  color: var(--text);
  font-weight: 700;
  font-size: 1.15rem;
}

.logo svg {
  border-radius: 10px;
  transition: transform var(--transition);
}

.logo:hover svg {
  transform: rotate(-6deg) scale(1.06);
}

.logo-text {
  background: var(--gradient-1);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  white-space: nowrap;
}

.main-nav {
  list-style: none;
  display: flex;
  gap: 4px;
  margin: 0;
  padding: 0;
  flex-wrap: wrap;
}

.main-nav a {
  display: block;
  padding: 6px 12px;
  font-size: 0.9rem;
  color: var(--text-muted);
  border-radius: var(--radius-full);
  transition: all var(--transition);
  white-space: nowrap;
}

.main-nav a:hover {
  color: var(--primary);
  background: rgba(26, 115, 232, 0.08);
}

.site-search {
  display: flex;
  align-items: center;
  margin-left: auto;
  gap: 6px;
}

.site-search input {
  width: 160px;
  padding: 8px 14px;
  font-size: 0.88rem;
  color: var(--text);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  outline: none;
  transition: all var(--transition);
}

.site-search input:focus {
  width: 200px;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(26, 115, 232, 0.15);
}

.site-search button {
  padding: 8px 16px;
  font-size: 0.88rem;
  color: #fff;
  background: var(--gradient-1);
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

.site-search button:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

#theme-toggle,
#menu-toggle {
  padding: 8px 14px;
  font-size: 0.85rem;
  color: var(--text-muted);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

#theme-toggle:hover,
#menu-toggle:hover {
  color: var(--primary);
  border-color: var(--primary);
  transform: translateY(-1px);
}

#menu-toggle {
  display: none;
}

/* ============ Main & Sections ============ */
main {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px 60px;
}

section {
  margin: 48px 0;
  scroll-margin-top: calc(var(--header-h) + 20px);
}

section h2 {
  font-size: 1.75rem;
  line-height: 1.35;
  margin: 0 0 20px;
  padding-bottom: 14px;
  position: relative;
  color: var(--text);
}

section h2::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 56px;
  height: 4px;
  border-radius: var(--radius-full);
  background: var(--gradient-1);
}

section h3 {
  font-size: 1.25rem;
  margin: 28px 0 12px;
  color: var(--text);
}

section h4 {
  font-size: 1.05rem;
  margin: 22px 0 10px;
  color: var(--primary);
}

section p {
  margin: 0 0 14px;
  color: var(--text-muted);
}

/* ============ Hero ============ */
#hero {
  margin-top: 28px;
  padding: 32px;
  border-radius: var(--radius-lg);
  background: var(--gradient-hero);
  background-size: 200% 200%;
  animation: gradientShift 12s ease infinite;
  box-shadow: var(--shadow-lg);
  position: relative;
  overflow: hidden;
}

#hero::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -20%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.25), transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

@keyframes gradientShift {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

.hero-slider {
  position: relative;
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  margin-bottom: 28px;
  background: rgba(0, 0, 0, 0.15);
}

.slide {
  display: none;
  animation: fadeSlide 0.6s ease;
}

.slide.active {
  display: block;
}

@keyframes fadeSlide {
  from { opacity: 0; transform: scale(1.02); }
  to { opacity: 1; transform: scale(1); }
}

.slide svg {
  width: 100%;
  height: auto;
  border-radius: var(--radius-md);
}

#hero-title {
  font-size: 1.9rem;
  line-height: 1.35;
  color: #fff;
  margin: 0 0 16px;
  text-shadow: 0 2px 12px rgba(0, 0, 0, 0.2);
}

.hero-lead {
  color: rgba(255, 255, 255, 0.92);
  font-size: 1rem;
  line-height: 1.8;
  margin: 0 0 28px;
  max-width: 900px;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.stat {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 18px 12px;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.16);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.28);
  transition: transform var(--transition), background var(--transition);
}

.stat:hover {
  transform: translateY(-4px);
  background: rgba(255, 255, 255, 0.26);
}

.stat .num {
  font-size: 1.9rem;
  font-weight: 800;
  color: #fff;
  line-height: 1.1;
  font-variant-numeric: tabular-nums;
}

.stat span:last-child {
  font-size: 0.82rem;
  color: rgba(255, 255, 255, 0.85);
  text-align: center;
}

/* ============ Breadcrumb ============ */
#breadcrumb {
  margin: 24px 0 0;
}

#breadcrumb ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  font-size: 0.88rem;
  color: var(--text-light);
}

#breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--text-light);
}

#breadcrumb a {
  color: var(--text-muted);
}

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

#breadcrumb [aria-current="page"] {
  color: var(--primary);
  font-weight: 600;
}

/* ============ Anchor Nav ============ */
#anchor-nav {
  margin: 24px 0;
  padding: 16px 20px;
  border-radius: var(--radius-md);
  background: var(--bg-card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}

#anchor-nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
}

#anchor-nav a {
  display: inline-block;
  padding: 6px 14px;
  font-size: 0.85rem;
  color: var(--text-muted);
  background: var(--bg);
  border-radius: var(--radius-full);
  border: 1px solid var(--border);
  transition: all var(--transition);
}

#anchor-nav a:hover {
  color: #fff;
  background: var(--gradient-1);
  border-color: transparent;
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

/* ============ Cards (sections) ============ */
#brand,
#history,
#culture,
#products,
#advantages,
#solutions,
#applications,
#cases,
#reviews,
#news,
#articles,
#knowledge,
#faq,
#howto,
#contact,
#sitemap,
#links {
  padding: 32px;
  border-radius: var(--radius-lg);
  background: var(--bg-card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition);
}

#brand:hover,
#products:hover,
#solutions:hover,
#cases:hover,
#articles:hover,
#faq:hover,
#howto:hover {
  box-shadow: var(--shadow-md);
}

/* ============ Articles ============ */
#articles article {
  padding: 20px 22px;
  margin-bottom: 16px;
  border-radius: var(--radius-md);
  background: var(--bg);
  border: 1px solid var(--border);
  border-left: 4px solid var(--primary);
  transition: all var(--transition);
}

#articles article:hover {
  transform: translateX(4px);
  box-shadow: var(--shadow-md);
  border-left-color: var(--secondary);
}

#articles article h3 {
  margin: 0 0 6px;
  font-size: 1.12rem;
  color: var(--text);
}

#articles article time {
  display: inline-block;
  font-size: 0.8rem;
  color: var(--text-light);
  margin-bottom: 8px;
}

#articles article p {
  margin: 0 0 10px;
  font-size: 0.92rem;
}

#articles article a {
  display: inline-block;
  font-size: 0.88rem;
  font-weight: 600;
  padding: 4px 0;
  position: relative;
}

#articles article a::after {
  content: "→";
  margin-left: 4px;
  transition: transform var(--transition);
  display: inline-block;
}

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

/* ============ News ============ */
#news article {
  padding: 20px 0;
  border-bottom: 1px dashed var(--border);
}

#news article:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

#news article h3 {
  margin: 0 0 6px;
  font-size: 1.1rem;
}

#news article time {
  font-size: 0.82rem;
  color: var(--text-light);
}

/* ============ Reviews ============ */
#reviews blockquote {
  margin: 0 0 18px;
  padding: 20px 24px;
  border-radius: var(--radius-md);
  background: var(--bg);
  border-left: 4px solid var(--secondary);
  position: relative;
  transition: all var(--transition);
}

#reviews blockquote:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

#reviews blockquote p {
  margin: 0 0 10px;
  font-style: italic;
  color: var(--text);
}

#reviews blockquote footer {
  font-size: 0.88rem;
  color: var(--text-light);
  text-align: right;
}

#reviews blockquote footer::before {
  content: "— ";
}

/* ============ FAQ ============ */
#faq details {
  margin-bottom: 12px;
  padding: 0;
  border-radius: var(--radius-md);
  background: var(--bg);
  border: 1px solid var(--border);
  overflow: hidden;
  transition: box-shadow var(--transition), border-color var(--transition);
}

#faq details[open] {
  border-color: var(--primary);
  box-shadow: var(--shadow-sm);
}

#faq summary {
  padding: 16px 20px;
  font-weight: 600;
  font-size: 0.98rem;
  color: var(--text);
  cursor: pointer;
  list-style: none;
  position: relative;
  padding-right: 48px;
  transition: color var(--transition), background var(--transition);
}

#faq summary::-webkit-details-marker {
  display: none;
}

#faq summary::after {
  content: "+";
  position: absolute;
  right: 20px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 1.4rem;
  font-weight: 400;
  color: var(--primary);
  line-height: 1;
  transition: transform var(--transition);
}

#faq details[open] summary::after {
  transform: translateY(-50%) rotate(45deg);
}

#faq summary:hover {
  color: var(--primary);
  background: rgba(26, 115, 232, 0.04);
}

#faq details p {
  padding: 0 20px 18px;
  margin: 0;
  font-size: 0.92rem;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ============ Contact ============ */
#contact address {
  font-style: normal;
  padding: 20px 24px;
  border-radius: var(--radius-md);
  background: var(--bg);
  border: 1px solid var(--border);
  margin-bottom: 18px;
}

#contact address p {
  margin: 0 0 8px;
}

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

/* ============ Sitemap & Links ============ */
#sitemap ul,
#links ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 0;
  padding: 0;
}

#sitemap a,
#links a {
  display: inline-block;
  padding: 6px 14px;
  font-size: 0.86rem;
  color: var(--text-muted);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  transition: all var(--transition);
}

#sitemap a:hover,
#links a:hover {
  color: #fff;
  background: var(--gradient-1);
  border-color: transparent;
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

/* ============ Footer ============ */
#site-footer {
  margin-top: 40px;
  padding: 48px 24px 32px;
  background: var(--bg-card);
  border-top: 1px solid var(--border);
}

.footer-info {
  max-width: var(--max-w);
  margin: 0 auto 32px;
  text-align: center;
}

.footer-info p {
  margin: 0 0 8px;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.footer-info nav ul {
  list-style: none;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 20px;
  margin: 16px 0 0;
  padding: 0;
}

.footer-info nav a {
  font-size: 0.86rem;
  color: var(--text-muted);
}

.footer-info nav a:hover {
  color: var(--primary);
}

#site-footer section {
  max-width: var(--max-w);
  margin: 0 auto 20px;
  padding: 20px 24px;
  border-radius: var(--radius-md);
  background: var(--bg);
  border: 1px solid var(--border);
}

#site-footer section h2 {
  font-size: 1.05rem;
  margin: 0 0 8px;
  padding-bottom: 0;
  color: var(--text);
}

#site-footer section h2::after {
  display: none;
}

#site-footer section p {
  margin: 0;
  font-size: 0.86rem;
  color: var(--text-muted);
}

/* ============ Back to Top ============ */
#back-to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 900;
  padding: 12px 18px;
  font-size: 0.85rem;
  font-weight: 600;
  color: #fff;
  background: var(--gradient-1);
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  box-shadow: var(--shadow-md);
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px);
  transition: all var(--transition);
}

#back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

#back-to-top:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

/* ============ Scroll Animation ============ */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s ease, transform 0.7s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.reveal.revealed {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
  .reveal {
    opacity: 1;
    transform: none;
  }
}

/* ============ Responsive ============ */
@media (max-width: 1024px) {
  .header-inner {
    flex-wrap: wrap;
    height: auto;
    padding: 12px 20px;
  }
  .main-nav {
    order: 3;
    width: 100%;
    justify-content: center;
  }
  .site-search input {
    width: 140px;
  }
  .site-search input:focus {
    width: 160px;
  }
  #hero-title {
    font-size: 1.6rem;
  }
  .hero-stats {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  body {
    font-size: 15px;
  }
  .header-inner {
    padding: 10px 16px;
    gap: 12px;
  }
  .main-nav {
    display: none;
    flex-direction: column;
    width: 100%;
    gap: 2px;
    padding: 8px 0;
  }
  .main-nav.open {
    display: flex;
  }
  .main-nav a {
    padding: 10px 14px;
    border-radius: var(--radius-sm);
  }
  #menu-toggle {
    display: block;
  }
  .site-search {
    flex: 1;
    margin-left: 0;
  }
  .site-search input {
    width: 100%;
    flex: 1;
  }
  .site-search input:focus {
    width: 100%;
  }
  .logo-text {
    font-size: 1rem;
  }
  main {
    padding: 0 16px 40px;
  }
  section {
    margin: 32px 0;
  }
  section h2 {
    font-size: 1.4rem;
  }
  section h3 {
    font-size: 1.12rem;
  }
  #hero {
    padding: 20px;
    border-radius: var(--radius-md);
  }
  #hero-title {
    font-size: 1.35rem;
  }
  .hero-lead {
    font-size: 0.92rem;
  }
  .stat {
    padding: 14px 8px;
  }
  .stat .num {
    font-size: 1.5rem;
  }
  .stat span:last-child {
    font-size: 0.75rem;
  }
  #brand,
  #history,
  #culture,
  #products,
  #advantages,
  #solutions,
  #applications,
  #cases,
  #reviews,
  #news,
  #articles,
  #knowledge,
  #faq,
  #howto,
  #contact,
  #sitemap,
  #links {
    padding: 20px 18px;
    border-radius: var(--radius-md);
  }
  #anchor-nav {
    padding: 12px 14px;
  }
  #anchor-nav a,
  #sitemap a,
  #links a {
    font-size: 0.8rem;
    padding: 5px 11px;
  }
  #articles article {
    padding: 16px 16px;
  }
  #faq summary {
    padding: 14px 16px;
    padding-right: 42px;
    font-size: 0.92rem;
  }
  #faq summary::after {
    right: 16px;
  }
  #faq details p {
    padding: 0 16px 14px;
  }
  #back-to-top {
    right: 16px;
    bottom: 16px;
    padding: 10px 14px;
    font-size: 0.8rem;
  }
  #site-footer {
    padding: 32px 16px 24px;
  }
  #site-footer section {
    padding: 16px 18px;
  }
}

@media (max-width: 480px) {
  .hero-stats {
    grid-template-columns: 1fr 1fr;
    gap: 10px;
  }
  .site-search button {
    padding: 8px 12px;
    font-size: 0.82rem;
  }
  #theme-toggle,
  #menu-toggle {
    padding: 8px 10px;
    font-size: 0.78rem;
  }
  .footer-info nav ul {
    gap: 12px;
  }
}

/* ============ Dark Mode Extra ============ */
[data-theme="dark"] .logo-text {
  background: linear-gradient(135deg, #6ea8ff 0%, #a29bfe 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

[data-theme="dark"] .site-search input {
  background: var(--bg-card);
}

[data-theme="dark"] #hero {
  box-shadow: 0 16px 48px rgba(0, 0, 0, 0.5);
}

[data-theme="dark"] #articles article {
  background: rgba(255, 255, 255, 0.02);
}

[data-theme="dark"] #reviews blockquote,
[data-theme="dark"] #contact address,
[data-theme="dark"] #faq details {
  background: rgba(255, 255, 255, 0.02);
}

[data-theme="dark"] #anchor-nav a,
[data-theme="dark"] #sitemap a,
[data-theme="dark"] #links a {
  background: rgba(255, 255, 255, 0.04);
}

/* ============ Print ============ */
@media print {
  #site-header,
  #back-to-top,
  #anchor-nav,
  .site-search,
  #theme-toggle,
  #menu-toggle,
  #hero {
    display: none !important;
  }
  body {
    background: #fff;
    color: #000;
  }
  section {
    box-shadow: none;
    border: 1px solid #ddd;
    page-break-inside: avoid;
  }
  a {
    color: #000;
    text-decoration: underline;
  }
}
</style>