/* ============================================
   Activated Carbon USA — Modern Static Site
   ============================================ */

/* --- Reset & Base --- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --color-bg: #0a0a0a;
  --color-surface: #111111;
  --color-surface-2: #1a1a1a;
  --color-surface-3: #222222;
  --color-border: #2a2a2a;
  --color-border-light: #333333;
  --color-text: #f5f5f5;
  --color-text-secondary: #a0a0a0;
  --color-text-muted: #666666;
  --color-accent: #D4A574;
  --color-accent-hover: #e0b88a;
  --color-accent-subtle: rgba(212, 165, 116, 0.1);
  --color-accent-glow: rgba(212, 165, 116, 0.15);
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-serif: 'Playfair Display', Georgia, serif;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1200px;
}

/* --- Light Theme --- */
[data-theme="light"] {
  --color-bg: #ffffff;
  --color-surface: #f7f7f7;
  --color-surface-2: #efefef;
  --color-surface-3: #e8e8e8;
  --color-border: #e0e0e0;
  --color-border-light: #d0d0d0;
  --color-text: #1a1a1a;
  --color-text-secondary: #555555;
  --color-text-muted: #888888;
  --color-accent: #b8885a;
  --color-accent-hover: #a67844;
  --color-accent-subtle: rgba(184, 136, 90, 0.1);
  --color-accent-glow: rgba(184, 136, 90, 0.12);
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) {
    --color-bg: #ffffff;
    --color-surface: #f7f7f7;
    --color-surface-2: #efefef;
    --color-surface-3: #e8e8e8;
    --color-border: #e0e0e0;
    --color-border-light: #d0d0d0;
    --color-text: #1a1a1a;
    --color-text-secondary: #555555;
    --color-text-muted: #888888;
    --color-accent: #b8885a;
    --color-accent-hover: #a67844;
    --color-accent-subtle: rgba(184, 136, 90, 0.1);
    --color-accent-glow: rgba(184, 136, 90, 0.12);
  }
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.7;
  overflow-x: hidden;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

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

a {
  color: inherit;
  text-decoration: none;
}

/* --- Animations --- */
[data-animate] {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.7s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}

[data-animate].visible {
  opacity: 1;
  transform: translateY(0);
}

/* --- Navigation --- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 0 24px;
  background: rgba(10, 10, 10, 0.6);
  backdrop-filter: blur(12px) saturate(1.4);
  -webkit-backdrop-filter: blur(12px) saturate(1.4);
  transition: background var(--transition), backdrop-filter var(--transition), border-color var(--transition);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.nav.scrolled {
  background: rgba(10, 10, 10, 0.82);
  backdrop-filter: blur(24px) saturate(1.8);
  -webkit-backdrop-filter: blur(24px) saturate(1.8);
  border-bottom-color: var(--color-border);
}

[data-theme="light"] .nav {
  background: rgba(255, 255, 255, 0.6);
  border-bottom-color: rgba(0, 0, 0, 0.06);
}

[data-theme="light"] .nav.scrolled {
  background: rgba(255, 255, 255, 0.82);
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .nav {
    background: rgba(255, 255, 255, 0.6);
    border-bottom-color: rgba(0, 0, 0, 0.06);
  }
  :root:not([data-theme="dark"]) .nav.scrolled {
    background: rgba(255, 255, 255, 0.82);
  }
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .nav {
    background: rgba(10, 10, 10, 0.6);
    border-bottom-color: rgba(255, 255, 255, 0.06);
  }
  :root:not([data-theme="light"]) .nav.scrolled {
    background: rgba(10, 10, 10, 0.82);
  }
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 600;
  font-size: 15px;
  letter-spacing: -0.01em;
}

.nav-logo-img {
  width: 28px;
  height: 32px;
}

.nav-logo-accent {
  color: var(--color-accent);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-link {
  padding: 8px 16px;
  font-size: 14px;
  font-weight: 450;
  color: var(--color-text-secondary);
  border-radius: var(--radius-sm);
  transition: color var(--transition), background var(--transition);
}

.nav-link:hover {
  color: var(--color-text);
}

.nav-link-cta {
  background: var(--color-accent);
  color: var(--color-bg) !important;
  font-weight: 600;
  margin-left: 8px;
  border-radius: 100px;
  padding: 8px 20px;
}

.nav-link-cta:hover {
  background: var(--color-accent-hover);
}

/* --- Theme Toggle --- */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 50%;
  cursor: pointer;
  color: var(--color-text-secondary);
  transition: color var(--transition), border-color var(--transition), background var(--transition);
  margin-left: 8px;
}

.theme-toggle:hover {
  color: var(--color-accent);
  border-color: var(--color-accent);
}

/* In dark mode: show sun, hide moon */
.theme-icon-moon { display: none; }
.theme-icon-sun { display: block; }

/* In light mode: show moon, hide sun */
[data-theme="light"] .theme-icon-sun { display: none; }
[data-theme="light"] .theme-icon-moon { display: block; }

@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .theme-icon-sun { display: none; }
  :root:not([data-theme="dark"]) .theme-icon-moon { display: block; }
}

/* --- Theme-aware logo switching --- */
/* Default (dark mode): show dark-mode logo, hide light-mode logo */
.logo-light { display: none; }
.logo-dark { display: block; }

/* Light mode via attribute */
[data-theme="light"] .logo-dark { display: none; }
[data-theme="light"] .logo-light { display: block; }

/* Light mode via system preference */
@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .logo-dark { display: none; }
  :root:not([data-theme="dark"]) .logo-light { display: block; }
}

/* Light mode: product card hover shadow */
[data-theme="light"] .product-card:hover,
:root:not([data-theme="dark"]) .product-card:hover {
  box-shadow: 0 24px 64px rgba(0, 0, 0, 0.1);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .product-card:hover {
    box-shadow: 0 24px 64px rgba(0, 0, 0, 0.4);
  }
}

/* Light mode: hero title gradient */
[data-theme="light"] .hero-title {
  background: linear-gradient(135deg, var(--color-text) 0%, rgba(26, 26, 26, 0.75) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .hero-title {
    background: linear-gradient(135deg, var(--color-text) 0%, rgba(26, 26, 26, 0.75) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
  }
}

/* Light mode: hero background */
[data-theme="light"] .hero-bg,
:root:not([data-theme="dark"]) .hero-bg {
  background:
    radial-gradient(ellipse 80% 60% at 50% 0%, rgba(184, 136, 90, 0.08) 0%, transparent 60%),
    radial-gradient(ellipse 60% 50% at 80% 20%, rgba(184, 136, 90, 0.04) 0%, transparent 50%),
    var(--color-bg);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .hero-bg {
    background:
      radial-gradient(ellipse 80% 60% at 50% 0%, rgba(212, 165, 116, 0.08) 0%, transparent 60%),
      radial-gradient(ellipse 60% 50% at 80% 20%, rgba(212, 165, 116, 0.04) 0%, transparent 50%),
      var(--color-bg);
  }
}

/* Light mode: subtle pattern adjustment */
[data-theme="light"] .hero-bg::after {
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23000000' fill-opacity='0.02'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .hero-bg::after {
    background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23000000' fill-opacity='0.02'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
  }
}

.nav-scrim {
  display: none;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: var(--transition);
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 32px;
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: 600;
  border-radius: 100px;
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  text-align: center;
}

.btn-primary {
  background: var(--color-accent);
  color: var(--color-bg);
}

.btn-primary:hover {
  background: var(--color-accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 8px 32px rgba(212, 165, 116, 0.25);
}

.btn-outline {
  background: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-border-light);
}

.btn-outline:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  transform: translateY(-2px);
}

.btn-full {
  width: 100%;
}

/* --- Hero --- */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 120px 24px 80px;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 50% 0%, rgba(212, 165, 116, 0.08) 0%, transparent 60%),
    radial-gradient(ellipse 60% 50% at 80% 20%, rgba(212, 165, 116, 0.04) 0%, transparent 50%),
    var(--color-bg);
}

.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.015'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

.hero-content {
  position: relative;
  text-align: center;
  max-width: 800px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 20px;
  background: var(--color-accent-subtle);
  border: 1px solid rgba(212, 165, 116, 0.2);
  border-radius: 100px;
  font-size: 13px;
  font-weight: 600;
  color: var(--color-accent);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 32px;
}

.hero-badge-flag {
  width: 20px;
  height: 14px;
  border-radius: 2px;
}

.hero-title {
  font-family: var(--font-serif);
  font-size: clamp(3rem, 7vw, 5.5rem);
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
  padding-bottom: 0.05em;
  background: linear-gradient(135deg, var(--color-text) 0%, rgba(245, 245, 245, 0.7) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 16px;
  font-weight: 500;
  color: var(--color-accent);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 24px;
}

.hero-desc {
  font-size: 17px;
  line-height: 1.8;
  color: var(--color-text-secondary);
  max-width: 640px;
  margin: 0 auto 40px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 64px;
}

.hero-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 40px;
  padding-top: 48px;
  border-top: 1px solid var(--color-border);
}

.hero-stat {
  text-align: center;
}

.hero-stat-value {
  display: block;
  font-family: var(--font-serif);
  font-size: 28px;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 4px;
}

.hero-stat-label {
  font-size: 13px;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.hero-stat-divider {
  width: 1px;
  height: 40px;
  background: var(--color-border);
}

/* --- Sections --- */
.section {
  padding: 120px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 64px;
}

.section-tag {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--color-accent);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 16px;
}

.section-title {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.01em;
}

/* --- About --- */
.section-about {
  border-top: 1px solid var(--color-border);
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: start;
}

.about-text p {
  color: var(--color-text-secondary);
  font-size: 16px;
  margin-bottom: 20px;
  line-height: 1.8;
}

.about-text p:last-child {
  margin-bottom: 0;
}

.about-features {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.feature-card {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 24px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: border-color var(--transition), transform var(--transition);
}

.feature-card:hover {
  border-color: var(--color-accent);
  transform: translateX(4px);
}

.feature-icon {
  flex-shrink: 0;
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-accent-subtle);
  border-radius: var(--radius-md);
}

.feature-icon img {
  width: 32px;
  height: 32px;
}

.feature-value {
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 700;
  color: var(--color-accent);
}

.feature-info h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 4px;
}

.feature-info p {
  font-size: 14px;
  color: var(--color-text-muted);
  line-height: 1.5;
  margin-bottom: 0;
}

/* --- Products --- */
.section-products {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.products-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.product-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
}

.product-card:hover {
  border-color: var(--color-accent);
  transform: translateY(-8px);
  box-shadow: 0 24px 64px rgba(0, 0, 0, 0.4);
}

.product-image {
  position: relative;
  aspect-ratio: 16 / 10;
  overflow: hidden;
  margin-bottom: -1px;
  background: var(--color-surface-2);
}

.product-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 0.6s cubic-bezier(0.16, 1, 0.3, 1), opacity 0.5s ease;
  will-change: transform;
  opacity: 0;
}

.product-image img.loaded {
  opacity: 1;
}

.product-card:hover .product-image img {
  transform: scale(1.05);
}

.product-image::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 50%;
  background: linear-gradient(to top, var(--color-bg) 0%, transparent 100%);
  pointer-events: none;
  z-index: 1;
}


.product-content {
  padding: 28px;
  position: relative;
  z-index: 2;
  background: var(--color-bg);
}

.product-icon {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-accent-subtle);
  border-radius: var(--radius-sm);
  margin-bottom: 16px;
}

.product-icon img {
  width: 28px;
  height: 28px;
}

.product-content h3 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 8px;
}

.product-content p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* --- Advantages --- */
.advantages-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  max-width: 900px;
  margin: 0 auto;
}

.advantage-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 20px 24px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: border-color var(--transition);
}

.advantage-item:hover {
  border-color: var(--color-border-light);
}

.advantage-check {
  flex-shrink: 0;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-accent-subtle);
  border-radius: 50%;
  color: var(--color-accent);
  margin-top: 1px;
}

.advantage-item span {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* --- Applications --- */
.section-applications {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.applications-layout {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 28px;
  align-items: start;
}

.app-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 36px;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.app-card:hover {
  border-color: var(--color-border-light);
}

.app-card-highlight {
  background: var(--color-surface);
  border-color: rgba(212, 165, 116, 0.25);
}

.app-card-highlight:hover {
  border-color: rgba(212, 165, 116, 0.4);
}

.app-card h3 {
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 600;
  margin-bottom: 14px;
}

.app-card p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.app-industries {
  margin-top: 28px;
}

.app-industries h4 {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-muted);
  margin-bottom: 14px;
}

.app-industry-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
}

.app-industry {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-size: 13px;
  font-weight: 450;
  color: var(--color-text-secondary);
  transition: border-color var(--transition), background var(--transition);
}

.app-industry:hover {
  border-color: var(--color-accent);
  background: var(--color-accent-subtle);
}

.app-industry img {
  width: 22px;
  height: 22px;
}

.app-industry svg {
  flex-shrink: 0;
}

.applications-side {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.applications-side .app-card {
  padding: 28px 32px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.applications-side .app-card h3 {
  font-size: 17px;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.applications-side .app-card h3::before {
  content: '';
  width: 3px;
  height: 18px;
  background: var(--color-accent);
  border-radius: 2px;
  flex-shrink: 0;
}

.app-list {
  list-style: none;
}

.app-list li {
  padding: 8px 0;
  font-size: 13.5px;
  color: var(--color-text-secondary);
  border-bottom: 1px solid var(--color-border);
  position: relative;
  padding-left: 16px;
  line-height: 1.5;
}

.app-list li:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.app-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  width: 4px;
  height: 4px;
  background: var(--color-accent);
  border-radius: 50%;
  transform: translateY(-50%);
}

/* --- Contact --- */
.section-contact {
  padding-bottom: 80px;
}

.contact-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: start;
}

.contact-info .section-title {
  text-align: left;
}

.contact-desc {
  margin-top: 32px;
}

.contact-desc h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 12px;
}

.contact-desc p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.contact-details {
  margin-top: 32px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.contact-detail-group h4 {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--color-accent);
}

.contact-detail-group ul {
  list-style: none;
}

.contact-detail-group li {
  font-size: 14px;
  color: var(--color-text-secondary);
  padding: 4px 0;
  position: relative;
  padding-left: 14px;
}

.contact-detail-group li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 4px;
  height: 4px;
  background: var(--color-border-light);
  border-radius: 50%;
}

/* --- Form --- */
.contact-form-wrapper {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 40px;
}

.contact-form {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.form-group-full {
  grid-column: 1 / -1;
}

.form-group label {
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text-secondary);
}

.form-group input,
.form-group select,
.form-group textarea {
  padding: 12px 16px;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: 15px;
  color: var(--color-text);
  transition: border-color var(--transition), box-shadow var(--transition);
  outline: none;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-subtle);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: var(--color-text-muted);
}

.form-group select {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg width='12' height='8' viewBox='0 0 12 8' fill='none' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M1 1.5L6 6.5L11 1.5' stroke='%23666' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 16px center;
  padding-right: 40px;
}

.form-group textarea {
  resize: vertical;
  min-height: 100px;
}

.contact-form .btn {
  grid-column: 1 / -1;
  margin-top: 8px;
}

/* --- Form Validation --- */
.required {
  color: var(--color-accent);
  margin-left: 2px;
}

.form-error {
  display: none;
  font-size: 12px;
  color: #e53935;
  margin-top: 6px;
  line-height: 1.4;
}

.form-group.has-error input,
.form-group.has-error select,
.form-group.has-error textarea {
  border-color: #e53935;
  box-shadow: 0 0 0 3px rgba(229, 57, 53, 0.1);
}

.form-group.has-error .form-error {
  display: block;
}

.form-status {
  grid-column: 1 / -1;
  font-size: 14px;
  text-align: center;
  padding: 0;
  transition: all 0.3s ease;
}

.form-status.success {
  color: #2d8a4e;
  padding: 12px;
  background: rgba(45, 138, 78, 0.08);
  border-radius: var(--radius-sm);
}

.form-status.error {
  color: #e53935;
  padding: 12px;
  background: rgba(229, 57, 53, 0.08);
  border-radius: var(--radius-sm);
}

/* --- Footer --- */
.footer {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  padding: 64px 0 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr repeat(3, 1fr);
  gap: 48px;
  padding-bottom: 48px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 600;
  font-size: 15px;
  margin-bottom: 16px;
}

.footer-logo img {
  width: 24px;
  height: 28px;
}

.footer-logo-accent {
  color: var(--color-accent);
}

.footer-tagline {
  font-size: 14px;
  color: var(--color-text-muted);
  line-height: 1.7;
}

.footer-col h4 {
  font-size: 13px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-muted);
  margin-bottom: 20px;
}

.footer-col a {
  display: block;
  font-size: 14px;
  color: var(--color-text-secondary);
  padding: 6px 0;
  transition: color var(--transition);
}

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

.footer-disclosure {
  border-top: 1px solid var(--color-border);
  padding: 20px 0;
  margin-bottom: 0;
}

.footer-disclosure p {
  font-size: 12px;
  line-height: 1.6;
  color: var(--color-text-muted);
  max-width: 680px;
  margin: 0 auto;
  text-align: center;
}

.footer-bottom {
  border-top: 1px solid var(--color-border);
  padding: 24px 0;
  text-align: center;
  font-size: 13px;
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.footer-flag {
  width: 18px;
  height: auto;
}

.footer-credit-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--color-text-muted);
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-credit-link .footer-flag {
  flex-shrink: 0;
}

.footer-credit-link:hover {
  color: var(--color-accent);
}

/* --- Skip Link (accessibility) --- */
.skip-link {
  position: absolute;
  top: -100%;
  left: 16px;
  z-index: 10000;
  padding: 12px 24px;
  background: var(--color-accent);
  color: #fff;
  font-size: 14px;
  font-weight: 600;
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 16px;
}

/* --- Back to Top --- */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  z-index: 900;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 50%;
  color: var(--color-text-secondary);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 0.3s ease, visibility 0.3s ease, transform 0.3s ease, color 0.2s ease, border-color 0.2s ease, background 0.2s ease;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
}

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

.back-to-top:hover {
  color: var(--color-accent);
  border-color: var(--color-accent);
  background: var(--color-accent-subtle);
}

.back-to-top:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* --- Focus Visible (accessibility) --- */
a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* --- Reduced Motion (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;
  }

  [data-animate] {
    opacity: 1 !important;
    transform: none !important;
  }

  .product-image img {
    opacity: 1 !important;
  }
}

/* ============================================
   Responsive
   ============================================ */

@media (max-width: 1024px) {
  .about-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .products-grid {
    grid-template-columns: 1fr 1fr;
  }

  .applications-layout {
    grid-template-columns: 1fr;
  }

  .contact-layout {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }
}

@media (max-width: 768px) {
  .nav-inner {
    position: relative;
  }

  .nav-links {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    z-index: 999;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    flex-direction: column;
    align-items: stretch;
    padding: 16px 24px 24px;
    gap: 4px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-12px);
    transition: opacity var(--transition), visibility var(--transition), transform var(--transition);
    box-shadow: 0 16px 48px rgba(0, 0, 0, 0.2);
  }

  .nav-scrim {
    display: block;
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 998;
    background: rgba(0, 0, 0, 0.4);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition), visibility var(--transition);
    -webkit-backdrop-filter: blur(4px);
    backdrop-filter: blur(4px);
  }

  .nav-scrim.open {
    opacity: 1;
    visibility: visible;
  }

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

  .nav-link {
    padding: 14px 16px;
    font-size: 16px;
    border-radius: var(--radius-sm);
  }

  .nav-link:hover {
    background: var(--color-surface-2);
  }

  .nav-link-cta {
    margin-left: 0;
    margin-top: 8px;
    text-align: center;
  }

  .theme-toggle {
    margin-left: auto;
    margin-right: 4px;
  }

  .nav-toggle {
    display: flex;
  }

  .nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }

  .nav-toggle.active span:nth-child(2) {
    opacity: 0;
  }

  .nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
  }

  .section {
    padding: 80px 0;
  }

  .hero {
    padding: 100px 24px 60px;
    min-height: auto;
  }

  .hero-stats {
    flex-direction: column;
    gap: 24px;
  }

  .hero-stat-divider {
    width: 40px;
    height: 1px;
  }

  .products-grid {
    grid-template-columns: 1fr;
  }

  .advantages-grid {
    grid-template-columns: 1fr;
  }

  .app-industry-grid {
    grid-template-columns: 1fr 1fr;
  }

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

  .contact-form-wrapper {
    padding: 24px;
  }

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

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 2.5rem;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .app-industry-grid {
    grid-template-columns: 1fr;
  }

  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 40px;
    height: 40px;
  }
}