:root {
  --brand: #1a73e8;
  --brand-dark: #1557b0;
  --brand-light: #4a90e2;
  --accent: #ff6b35;
  --accent-light: #ff8f5e;
  --gradient-1: linear-gradient(135deg, #1a73e8 0%, #6c5ce7 50%, #a29bfe 100%);
  --gradient-2: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --gradient-3: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  --gradient-hero: linear-gradient(135deg, #0c3483 0%, #1a73e8 40%, #6c5ce7 70%, #a29bfe 100%);
  --bg: #f5f7fb;
  --bg-alt: #ffffff;
  --bg-card: rgba(255, 255, 255, 0.72);
  --bg-glass: rgba(255, 255, 255, 0.55);
  --bg-glass-strong: rgba(255, 255, 255, 0.82);
  --text: #1a1d27;
  --text-secondary: #4a5068;
  --text-muted: #7a8199;
  --border: rgba(26, 115, 232, 0.12);
  --border-strong: rgba(26, 115, 232, 0.22);
  --shadow-sm: 0 2px 8px rgba(26, 115, 232, 0.06);
  --shadow-md: 0 8px 24px rgba(26, 115, 232, 0.10);
  --shadow-lg: 0 16px 48px rgba(26, 115, 232, 0.14);
  --shadow-glow: 0 0 40px rgba(26, 115, 232, 0.18);
  --radius-sm: 10px;
  --radius: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --blur: 18px;
  --transition: 0.35s cubic-bezier(0.25, 0.8, 0.25, 1);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --max-width: 1180px;
  --header-height: 68px;
}

[data-theme="dark"] {
  --brand: #4a90e2;
  --brand-dark: #3a7bd5;
  --brand-light: #6ba3f0;
  --accent: #ff8f5e;
  --gradient-1: linear-gradient(135deg, #2a4a8a 0%, #4a3a7a 50%, #6a5a9a 100%);
  --gradient-2: linear-gradient(135deg, #3a4a7a 0%, #5a3a6a 100%);
  --gradient-hero: linear-gradient(135deg, #0a1a3a 0%, #1a3a6a 40%, #3a2a6a 70%, #5a4a8a 100%);
  --bg: #0d1117;
  --bg-alt: #161b22;
  --bg-card: rgba(30, 38, 52, 0.72);
  --bg-glass: rgba(30, 38, 52, 0.55);
  --bg-glass-strong: rgba(30, 38, 52, 0.85);
  --text: #e6edf3;
  --text-secondary: #b0b8c8;
  --text-muted: #7a8299;
  --border: rgba(74, 144, 226, 0.15);
  --border-strong: rgba(74, 144, 226, 0.28);
  --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);
  --shadow-glow: 0 0 40px rgba(74, 144, 226, 0.15);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 20px);
  -webkit-text-size-adjust: 100%;
}

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

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

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

a:hover {
  color: var(--brand-light);
}

ul,
ol {
  list-style: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
  color: inherit;
}

input,
button {
  font-size: inherit;
}

.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: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-height);
  background: var(--bg-glass-strong);
  backdrop-filter: blur(var(--blur)) saturate(180%);
  -webkit-backdrop-filter: blur(var(--blur)) saturate(180%);
  border-bottom: 1px solid var(--border);
  transition: background var(--transition), box-shadow var(--transition), border-color var(--transition);
}

#site-header.scrolled {
  box-shadow: var(--shadow-md);
  border-bottom-color: var(--border-strong);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  gap: 20px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
  color: var(--text);
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: -0.01em;
}

.brand:hover {
  color: var(--brand);
}

.brand svg {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  transition: transform var(--transition);
}

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

.brand-text {
  background: var(--gradient-1);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.main-nav {
  flex: 1;
  display: flex;
  justify-content: center;
}

.main-nav ul {
  display: flex;
  gap: 4px;
  align-items: center;
}

.main-nav a {
  display: block;
  padding: 8px 14px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
  white-space: nowrap;
}

.main-nav a:hover {
  color: var(--brand);
  background: rgba(26, 115, 232, 0.08);
  transform: translateY(-1px);
}

.site-search {
  display: flex;
  align-items: center;
  gap: 0;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 50px;
  overflow: hidden;
  transition: border-color var(--transition), box-shadow var(--transition);
  flex-shrink: 0;
}

.site-search:focus-within {
  border-color: var(--brand);
  box-shadow: 0 0 0 3px rgba(26, 115, 232, 0.12);
}

.site-search input {
  border: none;
  outline: none;
  background: transparent;
  padding: 9px 16px;
  width: 170px;
  color: var(--text);
  font-size: 0.88rem;
}

.site-search input::placeholder {
  color: var(--text-muted);
}

.site-search button {
  padding: 9px 18px;
  background: var(--gradient-1);
  color: #fff;
  font-size: 0.85rem;
  font-weight: 600;
  transition: opacity var(--transition);
  white-space: nowrap;
}

.site-search button:hover {
  opacity: 0.88;
}

#theme-toggle {
  padding: 8px 14px;
  border-radius: 50px;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-secondary);
  border: 1px solid var(--border);
  background: var(--bg-card);
  transition: all var(--transition);
  flex-shrink: 0;
  white-space: nowrap;
}

#theme-toggle:hover {
  color: var(--brand);
  border-color: var(--brand);
  box-shadow: var(--shadow-sm);
}

#menu-toggle {
  display: none;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  border: 1px solid var(--border);
  background: var(--bg-card);
  transition: all var(--transition);
}

/* ============ Hero ============ */
.hero {
  position: relative;
  margin-top: var(--header-height);
  min-height: 560px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  overflow: hidden;
  background: var(--gradient-hero);
  background-size: 300% 300%;
  animation: heroGradient 12s ease infinite;
}

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

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 30%, rgba(255, 255, 255, 0.12) 0%, transparent 50%),
    radial-gradient(circle at 80% 70%, rgba(255, 255, 255, 0.08) 0%, transparent 50%),
    radial-gradient(circle at 50% 100%, rgba(0, 0, 0, 0.15) 0%, transparent 60%);
  pointer-events: none;
}

.hero::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 80px;
  background: var(--bg);
  clip-path: ellipse(75% 100% at 50% 100%);
  pointer-events: none;
}

.hero-slides {
  position: relative;
  width: 100%;
  max-width: var(--max-width);
  padding: 0 40px;
  z-index: 2;
}

.hero-slide {
  display: none;
  text-align: center;
  color: #fff;
  animation: slideFadeIn 0.7s ease both;
}

.hero-slide.is-active {
  display: block;
}

@keyframes slideFadeIn {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.hero-slide h1,
.hero-slide h2 {
  font-size: clamp(1.6rem, 4vw, 2.6rem);
  font-weight: 800;
  line-height: 1.3;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
  text-shadow: 0 2px 20px rgba(0, 0, 0, 0.2);
}

.hero-slide h1 {
  background: linear-gradient(135deg, #ffffff 0%, #d0e0ff 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-slide p {
  font-size: clamp(0.95rem, 1.6vw, 1.12rem);
  line-height: 1.85;
  max-width: 780px;
  margin: 0 auto 18px;
  color: rgba(255, 255, 255, 0.88);
}

.hero-cta {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 28px !important;
}

.hero-cta a {
  display: inline-block;
  padding: 13px 32px;
  border-radius: 50px;
  font-weight: 600;
  font-size: 0.95rem;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

.hero-cta a:first-child {
  background: #fff;
  color: var(--brand-dark);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
}

.hero-cta a:first-child:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.28);
  color: var(--brand-dark);
}

.hero-cta a:last-child {
  background: rgba(255, 255, 255, 0.12);
  color: #fff;
  border: 1.5px solid rgba(255, 255, 255, 0.45);
  backdrop-filter: blur(8px);
}

.hero-cta a:last-child:hover {
  background: rgba(255, 255, 255, 0.22);
  transform: translateY(-3px);
  color: #fff;
}

.hero-dots {
  display: flex;
  gap: 12px;
  justify-content: center;
  margin-top: 44px;
  z-index: 3;
  position: relative;
}

.hero-dots button {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  font-size: 0.82rem;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.7);
  background: rgba(255, 255, 255, 0.12);
  border: 1.5px solid rgba(255, 255, 255, 0.3);
  backdrop-filter: blur(8px);
  transition: all var(--transition);
}

.hero-dots button:hover {
  background: rgba(255, 255, 255, 0.25);
  color: #fff;
  transform: scale(1.1);
}

.hero-dots button[aria-selected="true"] {
  background: #fff;
  color: var(--brand-dark);
  border-color: #fff;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
}

/* ============ Breadcrumb ============ */
.breadcrumb {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 24px 24px 0;
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.breadcrumb li {
  display: flex;
  align-items: center;
  gap: 6px;
}

.breadcrumb li + li::before {
  content: "›";
  color: var(--text-muted);
  font-size: 1rem;
  margin-right: 2px;
}

.breadcrumb a {
  color: var(--text-secondary);
  font-weight: 500;
}

.breadcrumb a:hover {
  color: var(--brand);
}

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

/* ============ Sections ============ */
main > section {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 64px 24px;
}

main > section:first-of-type {
  padding-top: 0;
}

main > section h2 {
  font-size: clamp(1.4rem, 2.8vw, 1.9rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.3;
  margin-bottom: 24px;
  color: var(--text);
  position: relative;
  padding-left: 20px;
}

main > section h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.15em;
  bottom: 0.15em;
  width: 5px;
  border-radius: 4px;
  background: var(--gradient-1);
}

main > section h3 {
  font-size: clamp(1.05rem, 1.8vw, 1.25rem);
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 32px 0 12px;
  color: var(--text);
}

main > section p {
  font-size: 0.96rem;
  line-height: 1.9;
  color: var(--text-secondary);
  margin-bottom: 14px;
}

main > section ul,
main > section ol {
  margin: 14px 0;
  padding-left: 0;
}

main > section ul li,
main > section ol li {
  position: relative;
  padding: 10px 0 10px 28px;
  font-size: 0.94rem;
  line-height: 1.8;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border);
  transition: background var(--transition), padding-left var(--transition);
}

main > section ul li:last-child,
main > section ol li:last-child {
  border-bottom: none;
}

main > section ul li::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 1.15em;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--gradient-1);
  box-shadow: 0 0 0 3px rgba(26, 115, 232, 0.12);
}

main > section ol {
  counter-reset: step-counter;
}

main > section ol li {
  counter-increment: step-counter;
  padding-left: 40px;
}

main > section ol li::before {
  content: counter(step-counter);
  position: absolute;
  left: 0;
  top: 0.75em;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--gradient-1);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  line-height: 1;
}

/* ============ Stats ============ */
.stats {
  background: var(--bg-alt);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border);
  padding: 48px 40px !important;
  margin-top: 48px !important;
  position: relative;
  overflow: hidden;
}

.stats::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--gradient-1);
}

.stats h2 {
  text-align: center;
  padding-left: 0 !important;
  margin-bottom: 36px !important;
}

.stats h2::before {
  display: none;
}

.stats ul {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.stats li {
  text-align: center;
  padding: 20px 12px !important;
  border-bottom: none !important;
  border-radius: var(--radius);
  background: var(--bg-glass);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border);
  transition: all var(--transition);
}

.stats li::before {
  display: none !important;
}

.stats li:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: var(--border-strong);
}

.stats strong {
  display: block;
  font-size: clamp(1.6rem, 3.5vw, 2.4rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  background: var(--gradient-1);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1.2;
  margin-bottom: 6px;
}

.stats span {
  display: block;
  font-size: 0.85rem;
  color: var(--text-muted);
  font-weight: 500;
}

/* ============ Advantages ============ */
#advantages ul {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
  margin-top: 24px;
}

#advantages li {
  padding: 24px !important;
  border-radius: var(--radius);
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border) !important;
  border-bottom: 1px solid var(--border) !important;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

#advantages li::before {
  display: none !important;
}

#advantages li::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--gradient-1);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition);
}

#advantages li:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--border-strong) !important;
}

#advantages li:hover::after {
  transform: scaleX(1);
}

#advantages strong {
  display: block;
  color: var(--text);
  font-weight: 700;
  margin-bottom: 6px;
  font-size: 1rem;
}

/* ============ Applications ============ */
#applications ul {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 16px;
}

#applications li {
  padding: 18px 20px 18px 44px !important;
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border) !important;
  border-bottom: 1px solid var(--border) !important;
  font-size: 0.92rem;
  transition: all var(--transition);
}

#applications li::before {
  left: 20px !important;
  top: 50% !important;
  transform: translateY(-50%);
}

#applications li:hover {
  transform: translateX(4px);
  border-color: var(--border-strong) !important;
  box-shadow: var(--shadow-sm);
}

/* ============ Cases ============ */
#cases blockquote {
  position: relative;
  margin: 24px 0;
  padding: 28px 28px 28px 56px;
  border-radius: var(--radius);
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition);
}

#cases blockquote::before {
  content: "\201C";
  position: absolute;
  left: 18px;
  top: 10px;
  font-size: 3.2rem;
  line-height: 1;
  color: var(--brand);
  opacity: 0.3;
  font-family: Georgia, serif;
}

#cases blockquote:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--border-strong);
  transform: translateY(-3px);
}

#cases blockquote p {
  margin-bottom: 0;
  font-style: italic;
  color: var(--text-secondary);
}

/* ============ News ============ */
#news > ul {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
}

#news > ul > li {
  padding: 24px !important;
  border-radius: var(--radius);
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border) !important;
  border-bottom: 1px solid var(--border) !important;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition);
}

#news > ul > li::before {
  display: none !important;
}

#news > ul > li:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--border-strong) !important;
}

#news h3 {
  margin: 0 0 8px !important;
  font-size: 1.05rem !important;
}

#news h3 a {
  color: var(--text);
  font-weight: 700;
  transition: color var(--transition);
}

#news h3 a:hover {
  color: var(--brand);
}

#news > ul > li > p {
  font-size: 0.85rem;
  margin-bottom: 6px;
}

#news > ul > li > p:first-of-type {
  color: var(--brand);
  font-weight: 600;
  font-size: 0.8rem;
}

/* ============ Articles ============ */
#articles {
  background: var(--bg-alt);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border);
  padding: 48px 40px !important;
  margin-top: 48px !important;
}

#articles > p {
  margin-bottom: 28px;
}

#articles article {
  padding: 24px;
  margin-bottom: 16px;
  border-radius: var(--radius);
  background: var(--bg-glass);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border);
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

#articles article::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: var(--gradient-1);
  transform: scaleY(0);
  transform-origin: top;
  transition: transform var(--transition);
}

#articles article:hover {
  transform: translateX(6px);
  box-shadow: var(--shadow-md);
  border-color: var(--border-strong);
}

#articles article:hover::before {
  transform: scaleY(1);
}

#articles article h3 {
  margin: 0 0 8px !important;
  font-size: 1.08rem !important;
}

#articles article h3 a {
  color: var(--text);
  font-weight: 700;
}

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

#articles article p {
  font-size: 0.88rem;
  margin-bottom: 6px;
}

#articles article p:first-of-type {
  color: var(--brand);
  font-weight: 600;
  font-size: 0.8rem;
}

#articles article p:last-of-type a {
  display: inline-block;
  margin-top: 6px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--brand);
  padding: 6px 16px;
  border-radius: 50px;
  background: rgba(26, 115, 232, 0.08);
  transition: all var(--transition);
}

#articles article p:last-of-type a:hover {
  background: var(--brand);
  color: #fff;
  transform: translateX(4px);
}

/* ============ HowTo ============ */
#howto {
  background: var(--bg-alt);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border);
  padding: 48px 40px !important;
  margin-top: 48px !important;
}

#howto ol {
  counter-reset: howto-counter;
}

#howto ol li {
  counter-increment: howto-counter;
  padding-left: 48px !important;
  position: relative;
}

#howto ol li::before {
  content: counter(howto-counter);
  position: absolute;
  left: 0;
  top: 0.7em;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--gradient-1);
  color: #fff;
  font-size: 0.8rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 12px rgba(26, 115, 232, 0.3);
}

#howto ul li::before {
  background: var(--gradient-2);
  box-shadow: 0 0 0 3px rgba(108, 92, 231, 0.12);
}

/* ============ FAQ ============ */
#faq details {
  margin-bottom: 12px;
  border-radius: var(--radius);
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: all var(--transition);
}

#faq details:hover {
  border-color: var(--border-strong);
  box-shadow: var(--shadow-md);
}

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

#faq summary {
  padding: 18px 24px;
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  transition: color var(--transition), background var(--transition);
  position: relative;
}

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

#faq summary::after {
  content: "+";
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: rgba(26, 115, 232, 0.08);
  color: var(--brand);
  font-size: 1.15rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
  line-height: 1;
}

#faq details[open] summary::after {
  content: "−";
  background: var(--brand);
  color: #fff;
  transform: rotate(180deg);
}

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

#faq details p {
  padding: 0 24px 20px;
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.85;
  color: var(--text-secondary);
  animation: faqFadeIn 0.35s ease both;
}

@keyframes faqFadeIn {
  from {
    opacity: 0;
    transform: translateY(-8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ============ Contact ============ */
#contact {
  background: var(--gradient-1);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  padding: 56px 40px !important;
  margin-top: 48px !important;
  color: #fff;
  position: relative;
  overflow: hidden;
}

#contact::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 85% 15%, rgba(255, 255, 255, 0.15) 0%, transparent 50%),
    radial-gradient(circle at 15% 85%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
  pointer-events: none;
}

#contact h2 {
  color: #fff !important;
  position: relative;
  z-index: 1;
}

#contact h2::before {
  background: rgba(255, 255, 255, 0.9) !important;
}

#contact h3 {
  color: rgba(255, 255, 255, 0.95) !important;
  position: relative;
  z-index: 1;
}

#contact p {
  color: rgba(255, 255, 255, 0.85) !important;
  position: relative;
  z-index: 1;
}

#contact address {
  font-style: normal;
  position: relative;
  z-index: 1;
}

#contact address ul {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 12px;
  margin: 24px 0;
}

#contact address li {
  padding: 16px 20px !important;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.12);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(255, 255, 255, 0.18) !important;
  border-bottom: 1px solid rgba(255, 255, 255, 0.18) !important;
  color: rgba(255, 255, 255, 0.92) !important;
  font-size: 0.9rem;
  transition: all var(--transition);
}

#contact address li::before {
  display: none !important;
}

#contact address li:hover {
  background: rgba(255, 255, 255, 0.2);
  transform: translateY(-3px);
}

#contact a {
  color: #fff !important;
  text-decoration: underline;
  text-underline-offset: 3px;
  font-weight: 600;
}

#contact a:hover {
  opacity: 0.85;
}

/* ============ Sitemap & Links ============ */
#sitemap ul,
#links ul {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 16px;
}

#sitemap li,
#links li {
  padding: 0 !important;
  border-bottom: none !important;
}

#sitemap li::before,
#links li::before {
  display: none !important;
}

#sitemap a,
#links a {
  display: inline-block;
  padding: 9px 20px;
  border-radius: 50px;
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--text-secondary);
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border);
  transition: all var(--transition);
}

#sitemap a:hover,
#links a:hover {
  color: #fff;
  background: var(--gradient-1);
  border-color: transparent;
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

/* ============ Editorial ============ */
#editorial ul {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 12px;
  margin-top: 16px;
}

#editorial li {
  padding: 14px 18px !important;
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border) !important;
  border-bottom: 1px solid var(--border) !important;
  font-size: 0.88rem;
  transition: all var(--transition);
}

#editorial li::before {
  display: none !important;
}

#editorial li:hover {
  border-color: var(--border-strong) !important;
  box-shadow: var(--shadow-sm);
  transform: translateY(-2px);
}

/* ============ Privacy & Disclaimer ============ */
#privacy,
#disclaimer {
  background: var(--bg-alt);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
  padding: 40px !important;
  margin-top: 32px !important;
}

/* ============ Footer ============ */
#site-footer {
  background: var(--bg-alt);
  border-top: 1px solid var(--border);
  margin-top: 64px;
  padding: 48px 24px 32px;
  transition: background var(--transition), border-color var(--transition);
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  text-align: center;
}

.footer-inner p {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 8px;
  line-height: 1.7;
}

.footer-inner nav {
  margin-top: 20px;
}

.footer-inner nav ul {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
}

.footer-inner nav a {
  display: inline-block;
  padding: 8px 18px;
  border-radius: 50px;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  border: 1px solid var(--border);
  transition: all var(--transition);
}

.footer-inner nav a:hover {
  color: var(--brand);
  border-color: var(--brand);
  background: rgba(26, 115, 232, 0.06);
  transform: translateY(-2px);
}

/* ============ Back to Top ============ */
#back-to-top {
  position: fixed;
  bottom: 28px;
  right: 28px;
  z-index: 900;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--gradient-1);
  color: #fff;
  font-size: 0;
  box-shadow: var(--shadow-lg), var(--shadow-glow);
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px) scale(0.9);
  transition: all var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
}

#back-to-top::before {
  content: "↑";
  font-size: 1.3rem;
  font-weight: 700;
  line-height: 1;
}

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

#back-to-top:hover {
  transform: translateY(-4px) scale(1.08);
  box-shadow: 0 20px 48px rgba(26, 115, 232, 0.35);
}

/* ============ Scroll Animation ============ */
.reveal {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.7s cubic-bezier(0.25, 0.8, 0.25, 1),
              transform 0.7s cubic-bezier(0.25, 0.8, 0.25, 1);
}

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

/* ============ Responsive ============ */
@media (max-width: 1024px) {
  .main-nav ul {
    gap: 0;
  }

  .main-nav a {
    padding: 8px 10px;
    font-size: 0.84rem;
  }

  .site-search input {
    width: 130px;
  }

  .stats ul {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 860px) {
  :root {
    --header-height: 60px;
  }

  #menu-toggle {
    display: block;
  }

  .main-nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--bg-glass-strong);
    backdrop-filter: blur(var(--blur)) saturate(180%);
    -webkit-backdrop-filter: blur(var(--blur)) saturate(180%);
    border-bottom: 1px solid var(--border);
    padding: 16px 24px 24px;
    transform: translateY(-120%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition);
    z-index: 999;
    max-height: calc(100vh - var(--header-height));
    overflow-y: auto;
  }

  .main-nav.open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .main-nav ul {
    flex-direction: column;
    gap: 4px;
  }

  .main-nav a {
    padding: 12px 16px;
    font-size: 0.95rem;
    border-radius: var(--radius-sm);
  }

  .site-search {
    display: none;
  }

  .hero {
    min-height: 480px;
  }

  .hero-slides {
    padding: 0 24px;
  }

  main > section {
    padding: 48px 20px;
  }

  .stats,
  #articles,
  #howto,
  #contact,
  #privacy,
  #disclaimer {
    padding: 36px 24px !important;
    border-radius: var(--radius-lg);
  }

  #articles article {
    padding: 20px;
  }

  #faq summary {
    padding: 16px 20px;
    font-size: 0.9rem;
  }

  #faq details p {
    padding: 0 20px 18px;
  }
}

@media (max-width: 600px) {
  body {
    font-size: 15px;
  }

  .header-inner {
    padding: 0 16px;
    gap: 12px;
  }

  .brand-text {
    font-size: 1rem;
  }

  .brand svg {
    width: 32px;
    height: 32px;
  }

  #theme-toggle {
    padding: 7px 10px;
    font-size: 0.75rem;
  }

  #menu-toggle {
    padding: 7px 10px;
    font-size: 0.78rem;
  }

  .hero {
    min-height: 440px;
  }

  .hero-slides {
    padding: 0 20px;
  }

  .hero-cta {
    flex-direction: column;
    align-items: center;
  }

  .hero-cta a {
    width: 100%;
    max-width: 280px;
    text-align: center;
  }

  .hero-dots button {
    width: 36px;
    height: 36px;
    font-size: 0.75rem;
  }

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

  main > section h2 {
    font-size: 1.3rem;
    padding-left: 16px;
    margin-bottom: 18px;
  }

  main > section h3 {
    font-size: 1.05rem;
    margin: 24px 0 10px;
  }

  .stats {
    padding: 28px 18px !important;
    border-radius: var(--radius);
  }

  .stats ul {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
  }

  .stats li {
    padding: 16px 8px !important;
  }

  .stats strong {
    font-size: 1.5rem;
  }

  #advantages ul,
  #applications ul,
  #news > ul,
  #contact address ul {
    grid-template-columns: 1fr;
  }

  #articles,
  #howto {
    padding: 28px 18px !important;
    border-radius: var(--radius);
  }

  #contact {
    padding: 32px 20px !important;
    border-radius: var(--radius);
  }

  #privacy,
  #disclaimer {
    padding: 28px 18px !important;
    border-radius: var(--radius);
  }

  #cases blockquote {
    padding: 24px 20px 24px 48px;
  }

  #cases blockquote::before {
    left: 14px;
    font-size: 2.6rem;
  }

  #faq summary {
    padding: 14px 16px;
    font-size: 0.88rem;
  }

  #faq summary::after {
    width: 24px;
    height: 24px;
    font-size: 1rem;
  }

  #faq details p {
    padding: 0 16px 16px;
    font-size: 0.86rem;
  }

  #sitemap a,
  #links a {
    padding: 8px 16px;
    font-size: 0.82rem;
  }

  #editorial ul {
    grid-template-columns: 1fr;
  }

  #back-to-top {
    bottom: 20px;
    right: 20px;
    width: 42px;
    height: 42px;
  }

  .footer-inner nav ul {
    flex-direction: column;
    align-items: center;
  }

  .footer-inner nav a {
    width: 100%;
    max-width: 240px;
    text-align: center;
  }
}

/* ============ Accessibility ============ */
@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;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}

:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 3px;
  border-radius: 4px;
}

::selection {
  background: rgba(26, 115, 232, 0.2);
  color: var(--text);
}

/* ============ Scrollbar ============ */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

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

::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border-radius: 50px;
  border: 2px solid var(--bg);
}

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

/* ============ Print ============ */
@media print {
  #site-header,
  #back-to-top,
  .hero-dots,
  .site-search,
  #theme-toggle,
  #menu-toggle {
    display: none !important;
  }

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

  .hero {
    background: #fff !important;
    min-height: auto;
    padding: 20px 0;
  }

  .hero-slide h1,
  .hero-slide h2 {
    color: #000 !important;
    -webkit-text-fill-color: #000 !important;
  }

  main > section {
    padding: 20px 0;
  }
}