:root {
  --bg: #f5f7fb;
  --bg-alt: #ffffff;
  --surface: #ffffff;
  --surface-glass: rgba(255, 255, 255, 0.72);
  --surface-glass-strong: rgba(255, 255, 255, 0.88);
  --border: rgba(26, 26, 46, 0.1);
  --text: #1a1a2e;
  --text-soft: #4a4a63;
  --text-muted: #6b6b85;
  --brand: #1a1a2e;
  --brand-2: #16213e;
  --accent: #f2b705;
  --accent-2: #e94560;
  --accent-3: #4a90e2;
  --gradient-hero: linear-gradient(135deg, #1a1a2e 0%, #16213e 45%, #0f3460 100%);
  --gradient-accent: linear-gradient(135deg, #f2b705 0%, #e94560 100%);
  --gradient-soft: linear-gradient(135deg, rgba(242, 183, 5, 0.12) 0%, rgba(74, 144, 226, 0.12) 100%);
  --shadow-sm: 0 2px 8px rgba(26, 26, 46, 0.06);
  --shadow-md: 0 8px 24px rgba(26, 26, 46, 0.1);
  --shadow-lg: 0 18px 48px rgba(26, 26, 46, 0.16);
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-pill: 999px;
  --header-h: 72px;
  --maxw: 1200px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

html[data-theme="dark"] {
  --bg: #0b0e1a;
  --bg-alt: #101526;
  --surface: #141a2e;
  --surface-glass: rgba(20, 26, 46, 0.72);
  --surface-glass-strong: rgba(20, 26, 46, 0.9);
  --border: rgba(255, 255, 255, 0.1);
  --text: #eef1f8;
  --text-soft: #c3c9d9;
  --text-muted: #9aa2b8;
  --brand: #eef1f8;
  --brand-2: #c9d2e6;
  --gradient-hero: linear-gradient(135deg, #0b0e1a 0%, #16213e 50%, #0f3460 100%);
  --gradient-soft: linear-gradient(135deg, rgba(242, 183, 5, 0.16) 0%, rgba(74, 144, 226, 0.16) 100%);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 18px 48px rgba(0, 0, 0, 0.6);
}

*,
*::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: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  font-size: 16px;
  line-height: 1.75;
  color: var(--text);
  background: var(--bg);
  background-image:
    radial-gradient(circle at 12% 8%, rgba(242, 183, 5, 0.08), transparent 42%),
    radial-gradient(circle at 88% 12%, rgba(74, 144, 226, 0.1), transparent 46%),
    radial-gradient(circle at 50% 100%, rgba(233, 69, 96, 0.06), transparent 50%);
  background-attachment: fixed;
  transition: background-color 0.4s var(--ease), color 0.4s var(--ease);
  overflow-x: hidden;
}

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

a {
  color: var(--accent-3);
  text-decoration: none;
  transition: color 0.25s var(--ease), opacity 0.25s var(--ease);
}

a:hover,
a:focus-visible {
  color: var(--accent-2);
}

h1, h2, h3, h4 {
  line-height: 1.3;
  color: var(--brand);
  margin: 0 0 0.6em;
  font-weight: 700;
  letter-spacing: 0.01em;
}

h1 {
  font-size: clamp(1.6rem, 3.4vw, 2.5rem);
}

h2 {
  font-size: clamp(1.35rem, 2.6vw, 1.9rem);
  position: relative;
  padding-left: 18px;
}

h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.18em;
  width: 6px;
  height: 1em;
  border-radius: var(--radius-pill);
  background: var(--gradient-accent);
}

h3 {
  font-size: clamp(1.1rem, 1.9vw, 1.3rem);
  color: var(--brand-2);
}

p {
  margin: 0 0 1em;
  color: var(--text-soft);
}

ul, ol {
  margin: 0 0 1em;
  padding-left: 1.4em;
  color: var(--text-soft);
}

li {
  margin-bottom: 0.45em;
}

blockquote {
  margin: 1.2em 0;
  padding: 1em 1.2em;
  border-left: 4px solid var(--accent);
  border-radius: var(--radius-sm);
  background: var(--surface-glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: var(--shadow-sm);
}

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

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

:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
  border-radius: 6px;
}

/* ============ Header ============ */
#site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--surface-glass);
  backdrop-filter: blur(18px) saturate(160%);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
  border-bottom: 1px solid var(--border);
  transition: background 0.4s var(--ease), box-shadow 0.4s var(--ease);
}

#site-header.is-scrolled {
  box-shadow: var(--shadow-md);
}

.header-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  min-height: var(--header-h);
  padding: 10px 20px;
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--brand);
  font-weight: 800;
  font-size: 1.15rem;
  letter-spacing: 0.02em;
  flex-shrink: 0;
}

.brand:hover,
.brand:focus-visible {
  color: var(--brand);
  opacity: 0.85;
}

.brand-logo {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  box-shadow: 0 0 0 2px rgba(242, 183, 5, 0.35), 0 6px 18px rgba(242, 183, 5, 0.28);
  transition: transform 0.5s var(--ease), box-shadow 0.4s var(--ease);
}

.brand:hover .brand-logo {
  transform: rotate(72deg) scale(1.06);
  box-shadow: 0 0 0 3px rgba(242, 183, 5, 0.55), 0 8px 26px rgba(242, 183, 5, 0.45);
}

.brand-name {
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.main-nav {
  flex: 1 1 auto;
  min-width: 0;
}

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

.main-nav li {
  margin: 0;
}

.main-nav a {
  display: inline-block;
  padding: 7px 12px;
  border-radius: var(--radius-pill);
  font-size: 0.9rem;
  color: var(--text-soft);
  font-weight: 500;
  transition: background 0.25s var(--ease), color 0.25s var(--ease), transform 0.25s var(--ease);
}

.main-nav a:hover,
.main-nav a:focus-visible {
  background: var(--gradient-soft);
  color: var(--brand);
  transform: translateY(-1px);
}

.site-search {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-shrink: 0;
}

.site-search input[type="search"] {
  width: 190px;
  padding: 8px 14px;
  font-size: 0.88rem;
  color: var(--text);
  background: var(--surface-glass-strong);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  outline: none;
  transition: width 0.35s var(--ease), border-color 0.25s var(--ease), box-shadow 0.25s var(--ease);
  -webkit-appearance: none;
  appearance: none;
}

.site-search input[type="search"]::placeholder {
  color: var(--text-muted);
}

.site-search input[type="search"]:focus {
  width: 230px;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(242, 183, 5, 0.22);
}

.site-search button {
  padding: 8px 16px;
  font-size: 0.86rem;
  font-weight: 600;
  color: #1a1a2e;
  background: var(--gradient-accent);
  border: none;
  border-radius: var(--radius-pill);
  cursor: pointer;
  transition: transform 0.22s var(--ease), box-shadow 0.25s var(--ease), filter 0.25s var(--ease);
}

.site-search button:hover,
.site-search button:focus-visible {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(233, 69, 96, 0.35);
  filter: brightness(1.05);
}

#theme-toggle,
#menu-toggle {
  padding: 8px 14px;
  font-size: 0.84rem;
  font-weight: 600;
  color: var(--text-soft);
  background: var(--surface-glass-strong);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  cursor: pointer;
  white-space: nowrap;
  transition: color 0.25s var(--ease), background 0.25s var(--ease), border-color 0.25s var(--ease), transform 0.22s var(--ease);
}

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

#menu-toggle {
  display: none;
}

/* ============ Layout ============ */
main {
  display: block;
}

main > section {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 56px 20px;
}

main > section + section {
  border-top: 1px solid var(--border);
}

/* ============ Hero ============ */
.hero {
  max-width: var(--maxw);
  margin: 24px auto 0;
  padding: 0 20px !important;
  border-top: none !important;
}

.hero-slides {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: 100%;
  gap: 20px;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  padding-bottom: 12px;
  scrollbar-width: thin;
  scrollbar-color: rgba(242, 183, 5, 0.5) transparent;
}

.hero-slides::-webkit-scrollbar {
  height: 6px;
}

.hero-slides::-webkit-scrollbar-thumb {
  background: rgba(242, 183, 5, 0.5);
  border-radius: var(--radius-pill);
}

.hero-slide {
  position: relative;
  scroll-snap-align: center;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  padding: 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--gradient-hero);
  box-shadow: var(--shadow-lg);
  isolation: isolate;
}

.hero-slide::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 78% 24%, rgba(242, 183, 5, 0.22), transparent 46%),
              radial-gradient(circle at 16% 84%, rgba(74, 144, 226, 0.24), transparent 50%);
  pointer-events: none;
  z-index: 1;
}

.hero-slide svg {
  width: 100%;
  height: 320px;
  object-fit: cover;
  opacity: 0.9;
  grid-area: 1 / 1;
  transition: transform 0.9s var(--ease);
}

.hero-slide:hover svg {
  transform: scale(1.04);
}

.hero-slide h2,
.hero-slide p,
.hero-slide a {
  position: relative;
  z-index: 2;
  grid-column: 1;
  margin-left: 32px;
  margin-right: 32px;
}

.hero-slide h2 {
  grid-row: 1;
  align-self: center;
  margin-top: -30px;
  margin-bottom: 0;
  color: #ffffff;
  text-shadow: 0 2px 18px rgba(0, 0, 0, 0.55);
  padding-left: 0;
  font-size: clamp(1.4rem, 3vw, 2.2rem);
}

.hero-slide h2::before {
  display: none;
}

.hero-slide p {
  grid-row: 1;
  align-self: center;
  margin-top: 70px;
  max-width: 620px;
  color: rgba(255, 255, 255, 0.88);
  font-size: clamp(0.9rem, 1.5vw, 1.02rem);
  text-shadow: 0 1px 12px rgba(0, 0, 0, 0.5);
}

.hero-slide a {
  grid-row: 1;
  align-self: center;
  justify-self: start;
  margin-top: 190px;
  padding: 10px 24px;
  font-size: 0.92rem;
  font-weight: 700;
  color: #1a1a2e;
  background: var(--gradient-accent);
  border-radius: var(--radius-pill);
  box-shadow: 0 10px 26px rgba(233, 69, 96, 0.35);
  transition: transform 0.28s var(--ease), box-shadow 0.28s var(--ease), filter 0.25s var(--ease);
}

.hero-slide a:hover,
.hero-slide a:focus-visible {
  color: #1a1a2e;
  transform: translateY(-3px) scale(1.03);
  box-shadow: 0 16px 36px rgba(233, 69, 96, 0.5);
  filter: brightness(1.06);
}

/* ============ Cards / surfaces ============ */
.brand-intro,
.products,
.solutions,
.cases,
.news,
.articles,
.industry-knowledge,
.faq,
.howto,
.contact,
.sitemap,
.friend-links {
  position: relative;
}

.lead {
  font-size: clamp(1rem, 1.6vw, 1.08rem);
  color: var(--text-soft);
  padding: 18px 22px;
  border-radius: var(--radius-md);
  background: var(--surface-glass);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  box-shadow: var(--shadow-sm);
}

/* Products */
.products > h3,
.solutions > h3,
.cases > h3,
.howto > h3,
.industry-knowledge > h3 {
  margin-top: 1.6em;
  padding: 14px 18px;
  border-radius: var(--radius-md);
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: transform 0.3s var(--ease), box-shadow 0.3s var(--ease), border-color 0.3s var(--ease);
}

.products > h3:hover,
.solutions > h3:hover,
.cases > h3:hover,
.howto > h3:hover,
.industry-knowledge > h3:hover {
  transform: translateY(-3px);
  border-color: rgba(242, 183, 5, 0.5);
  box-shadow: var(--shadow-md);
}

/* ============ News ============ */
.news-item {
  position: relative;
  margin: 0 0 20px;
  padding: 22px 24px;
  border-radius: var(--radius-md);
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease), border-color 0.35s var(--ease);
}

.news-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: var(--gradient-accent);
  transform: scaleY(0);
  transform-origin: top;
  transition: transform 0.4s var(--ease);
}

.news-item:hover {
  transform: translateY(-4px);
  border-color: rgba(242, 183, 5, 0.45);
  box-shadow: var(--shadow-md);
}

.news-item:hover::before {
  transform: scaleY(1);
}

.news-item h3 {
  margin-bottom: 6px;
}

.meta {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-bottom: 12px;
  letter-spacing: 0.01em;
}

/* ============ Articles ============ */
.articles {
  display: block;
}

.article-card {
  position: relative;
  margin: 0 0 20px;
  padding: 24px;
  border-radius: var(--radius-md);
  background: var(--surface-glass);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease), border-color 0.35s var(--ease), background 0.35s var(--ease);
}

.article-card:hover {
  transform: translateY(-5px);
  border-color: rgba(74, 144, 226, 0.5);
  background: var(--surface-glass-strong);
  box-shadow: var(--shadow-md);
}

.article-card h3 {
  margin-bottom: 6px;
  transition: color 0.3s var(--ease);
}

.article-card:hover h3 {
  color: var(--accent-2);
}

.article-card > a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 4px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--accent-2);
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  background: rgba(233, 69, 96, 0.1);
  transition: background 0.28s var(--ease), transform 0.28s var(--ease), gap 0.28s var(--ease);
}

.article-card > a::after {
  content: "→";
  transition: transform 0.28s var(--ease);
}

.article-card > a:hover,
.article-card > a:focus-visible {
  background: rgba(233, 69, 96, 0.2);
  transform: translateY(-1px);
  color: var(--accent-2);
}

.article-card > a:hover::after {
  transform: translateX(4px);
}

/* ============ FAQ ============ */
.faq details {
  margin-bottom: 12px;
  border-radius: var(--radius-md);
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: box-shadow 0.3s var(--ease), border-color 0.3s var(--ease);
}

.faq details[open] {
  border-color: rgba(242, 183, 5, 0.5);
  box-shadow: var(--shadow-md);
}

.faq details:hover {
  border-color: rgba(242, 183, 5, 0.35);
}

.faq summary {
  position: relative;
  padding: 16px 52px 16px 20px;
  font-weight: 600;
  color: var(--brand);
  cursor: pointer;
  list-style: none;
  transition: background 0.28s var(--ease), color 0.28s var(--ease);
}

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

.faq summary::after {
  content: "+";
  position: absolute;
  right: 18px;
  top: 50%;
  transform: translateY(-50%);
  width: 26px;
  height: 26px;
  display: grid;
  place-items: center;
  font-size: 1.15rem;
  font-weight: 700;
  color: #1a1a2e;
  background: var(--gradient-accent);
  border-radius: 50%;
  transition: transform 0.35s var(--ease);
}

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

.faq summary:hover {
  background: var(--gradient-soft);
}

.faq details > p {
  margin: 0;
  padding: 0 20px 18px;
  animation: faqIn 0.4s var(--ease);
}

@keyframes faqIn {
  from { opacity: 0; transform: translateY(-6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ============ HowTo ============ */
.howto ol {
  counter-reset: step;
  list-style: none;
  padding-left: 0;
}

.howto ol > li {
  position: relative;
  counter-increment: step;
  padding: 14px 18px 14px 58px;
  margin-bottom: 10px;
  border-radius: var(--radius-sm);
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: transform 0.3s var(--ease), box-shadow 0.3s var(--ease), border-color 0.3s var(--ease);
}

.howto ol > li::before {
  content: counter(step);
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  width: 30px;
  height: 30px;
  display: grid;
  place-items: center;
  font-size: 0.86rem;
  font-weight: 700;
  color: #1a1a2e;
  background: var(--gradient-accent);
  border-radius: 50%;
  box-shadow: 0 4px 12px rgba(233, 69, 96, 0.3);
}

.howto ol > li:hover {
  transform: translateX(4px);
  border-color: rgba(242, 183, 5, 0.45);
  box-shadow: var(--shadow-md);
}

/* ============ Contact ============ */
.contact-list {
  list-style: none;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 14px;
}

.contact-list li {
  margin: 0;
  padding: 16px 18px;
  border-radius: var(--radius-md);
  background: var(--surface-glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  color: var(--text-soft);
  transition: transform 0.3s var(--ease), box-shadow 0.3s var(--ease), border-color 0.3s var(--ease);
}

.contact-list li:hover {
  transform: translateY(-3px);
  border-color: rgba(74, 144, 226, 0.45);
  box-shadow: var(--shadow-md);
}

.contact-list strong {
  color: var(--brand);
}

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

.sitemap li,
.friend-links li {
  margin: 0;
}

.sitemap a,
.friend-links a {
  display: inline-block;
  padding: 8px 18px;
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--text-soft);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  box-shadow: var(--shadow-sm);
  transition: transform 0.28s var(--ease), color 0.28s var(--ease), border-color 0.28s var(--ease), background 0.28s var(--ease);
}

.sitemap a:hover,
.sitemap a:focus-visible,
.friend-links a:hover,
.friend-links a:focus-visible {
  color: var(--brand);
  background: var(--gradient-soft);
  border-color: var(--accent);
  transform: translateY(-2px);
}

/* ============ Footer ============ */
#site-footer {
  margin-top: 40px;
  padding: 56px 20px 32px;
  background: var(--gradient-hero);
  color: rgba(255, 255, 255, 0.82);
  position: relative;
  overflow: hidden;
}

#site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 88% 12%, rgba(242, 183, 5, 0.16), transparent 42%),
    radial-gradient(circle at 8% 88%, rgba(74, 144, 226, 0.18), transparent 46%);
  pointer-events: none;
}

#site-footer > section,
#site-footer > p {
  position: relative;
  max-width: var(--maxw);
  margin-left: auto;
  margin-right: auto;
}

#site-footer h2,
#site-footer h3 {
  color: #ffffff;
}

#site-footer h2 {
  font-size: 1.15rem;
  padding-left: 16px;
}

#site-footer h2::before {
  height: 0.9em;
}

#site-footer h3 {
  font-size: 1rem;
  margin-top: 1.2em;
  color: rgba(255, 255, 255, 0.92);
}

#site-footer p,
#site-footer li {
  color: rgba(255, 255, 255, 0.72);
  font-size: 0.9rem;
}

.footer-about,
.footer-info,
.footer-legal {
  padding: 22px 24px;
  margin-bottom: 20px;
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.footer-info ul {
  list-style: none;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 10px;
}

.footer-info li {
  margin: 0;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.05);
}

.copyright {
  text-align: center;
  padding-top: 12px;
  font-size: 0.84rem;
  color: rgba(255, 255, 255, 0.6) !important;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

/* ============ Back to top ============ */
#back-to-top {
  position: fixed;
  right: 22px;
  bottom: 24px;
  z-index: 90;
  width: 48px;
  height: 48px;
  padding: 0;
  font-size: 0;
  color: #1a1a2e;
  background: var(--gradient-accent);
  border: none;
  border-radius: 50%;
  cursor: pointer;
  box-shadow: 0 10px 26px rgba(233, 69, 96, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px) scale(0.9);
  transition: opacity 0.35s var(--ease), transform 0.35s var(--ease), visibility 0.35s var(--ease), box-shadow 0.3s var(--ease);
}

#back-to-top::before {
  content: "↑";
  font-size: 1.35rem;
  font-weight: 700;
  line-height: 1;
}

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

#back-to-top:hover,
#back-to-top:focus-visible {
  transform: translateY(-4px) scale(1.06);
  box-shadow: 0 16px 36px rgba(233, 69, 96, 0.55);
}

/* ============ Scroll animations ============ */
.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
  will-change: opacity, transform;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.reveal-delay-1 { transition-delay: 0.08s; }
.reveal-delay-2 { transition-delay: 0.16s; }
.reveal-delay-3 { transition-delay: 0.24s; }

@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 {
    gap: 12px;
  }
  .site-search input[type="search"] {
    width: 150px;
  }
  .site-search input[type="search"]:focus {
    width: 180px;
  }
  .main-nav a {
    padding: 6px 9px;
    font-size: 0.85rem;
  }
}

@media (max-width: 860px) {
  :root {
    --header-h: 64px;
  }

  .header-inner {
    flex-wrap: wrap;
    padding: 8px 16px;
  }

  #menu-toggle {
    display: inline-block;
    margin-left: auto;
  }

  .main-nav {
    order: 10;
    flex-basis: 100%;
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-height 0.45s var(--ease), opacity 0.35s var(--ease), margin 0.35s var(--ease);
  }

  .main-nav.is-open {
    max-height: 640px;
    opacity: 1;
    margin-top: 8px;
  }

  .main-nav ul {
    flex-direction: column;
    gap: 2px;
  }

  .main-nav a {
    display: block;
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    font-size: 0.92rem;
  }

  .site-search {
    order: 11;
    flex-basis: 100%;
    margin-top: 8px;
  }

  .site-search input[type="search"],
  .site-search input[type="search"]:focus {
    width: 100%;
    flex: 1;
  }

  main > section {
    padding: 40px 16px;
  }

  .hero {
    padding: 0 16px !important;
    margin-top: 16px;
  }

  .hero-slide svg {
    height: 260px;
  }

  .hero-slide h2,
  .hero-slide p,
  .hero-slide a {
    margin-left: 20px;
    margin-right: 20px;
  }

  .hero-slide h2 {
    margin-top: -20px;
  }

  .hero-slide p {
    margin-top: 62px;
  }

  .hero-slide a {
    margin-top: 168px;
  }
}

@media (max-width: 560px) {
  body {
    font-size: 15px;
  }

  .brand-name {
    font-size: 1.02rem;
  }

  .brand-logo {
    width: 34px;
    height: 34px;
  }

  #theme-toggle,
  #menu-toggle {
    padding: 7px 11px;
    font-size: 0.78rem;
  }

  .hero-slide svg {
    height: 230px;
  }

  .hero-slide h2 {
    margin-top: -6px;
    font-size: 1.28rem;
  }

  .hero-slide p {
    margin-top: 52px;
    font-size: 0.86rem;
  }

  .hero-slide a {
    margin-top: 150px;
    padding: 9px 20px;
    font-size: 0.85rem;
  }

  .lead {
    padding: 14px 16px;
  }

  .news-item,
  .article-card,
  .footer-about,
  .footer-info,
  .footer-legal {
    padding: 18px;
  }

  .contact-list {
    grid-template-columns: 1fr;
  }

  .howto ol > li {
    padding: 12px 14px 12px 52px;
  }

  #back-to-top {
    right: 14px;
    bottom: 16px;
    width: 42px;
    height: 42px;
  }
}

@media (hover: none) {
  .hero-slide:hover svg,
  .news-item:hover,
  .article-card:hover,
  .contact-list li:hover,
  .howto ol > li:hover,
  .products > h3:hover,
  .solutions > h3:hover,
  .cases > h3:hover,
  .howto > h3:hover,
  .industry-knowledge > h3:hover {
    transform: none;
  }
}

@media print {
  #site-header,
  #back-to-top,
  .site-search,
  #theme-toggle,
  #menu-toggle {
    display: none !important;
  }
  body {
    background: #fff;
    color: #000;
  }
  main > section {
    padding: 12px 0;
    border-top: none;
  }
}