/* ============================================
   ZENTRIFLUX — Design Tokens
   Dark industrial German engineering aesthetic
   ============================================ */

:root {
  /* Type Scale */
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  --text-lg: clamp(1.125rem, 1rem + 0.75vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.25vw, 2.25rem);
  --text-2xl: clamp(2rem, 1.2rem + 2.5vw, 3.5rem);
  --text-3xl: clamp(2.5rem, 1rem + 4vw, 5rem);

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.375rem;
  --radius-lg: 0.5rem;

  /* Content widths */
  --content-narrow: 640px;
  --content-default: 960px;
  --content-wide: 1200px;

  /* Transition */
  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  /* Fonts */
  --font-display: 'Cabinet Grotesk', 'Helvetica Neue', sans-serif;
  --font-body: 'Switzer', 'Helvetica Neue', sans-serif;

  /* Dark theme — default and only mode */
  --color-bg: #0a0b0d;
  --color-surface: #111318;
  --color-surface-2: #181b22;
  --color-surface-3: #1e222b;
  --color-border: #2a2e38;
  --color-border-subtle: rgba(255, 255, 255, 0.06);
  --color-text: #e8eaed;
  --color-text-muted: #8b919e;
  --color-text-faint: #4f5563;
  --color-primary: #00c9d6;
  --color-primary-hover: #00e0ee;
  --color-primary-dim: rgba(0, 201, 214, 0.12);
  --color-primary-glow: rgba(0, 201, 214, 0.06);
  --color-accent: #ff6b35;

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.6);
}

/* ============================================
   Layout
   ============================================ */

.container {
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

.container--narrow {
  max-width: var(--content-default);
}

/* ============================================
   Header / Navigation
   ============================================ */

.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(10, 11, 13, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-border-subtle);
  padding: var(--space-4) 0;
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.header__logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-text);
}

.header__logo-mark {
  width: 36px;
  height: 36px;
}

.header__logo-text {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--text-sm);
  letter-spacing: 0.15em;
  text-transform: uppercase;
}

.header__nav {
  display: flex;
  align-items: center;
  gap: var(--space-8);
}

.header__nav a {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  text-decoration: none;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  font-weight: 500;
  position: relative;
}

.header__nav a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--color-primary);
  transition: width 0.3s ease;
}

.header__nav a:hover {
  color: var(--color-text);
}

.header__nav a:hover::after {
  width: 100%;
}

.mobile-menu-btn {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--space-2);
}

.mobile-menu-btn span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-text);
  transition: all 0.3s ease;
}

/* ============================================
   Hero Section
   ============================================ */

.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  padding-top: var(--space-16);
}

.hero__bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero__bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.45;
}

.hero__bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(
    to right,
    rgba(10, 11, 13, 0.95) 0%,
    rgba(10, 11, 13, 0.7) 40%,
    rgba(10, 11, 13, 0.3) 100%
  );
}

.hero__content {
  position: relative;
  z-index: 1;
  max-width: 640px;
  padding: var(--space-16) 0;
}

.hero__tag {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-6);
  padding: var(--space-2) var(--space-4);
  border: 1px solid var(--color-primary);
  border-radius: var(--radius-sm);
  background: var(--color-primary-dim);
}

.hero__title {
  font-family: var(--font-display);
  font-size: var(--text-3xl);
  font-weight: 800;
  color: var(--color-text);
  margin-bottom: var(--space-6);
  line-height: 1.05;
  letter-spacing: -0.02em;
}

.hero__title span {
  color: var(--color-primary);
}

.hero__subtitle {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  margin-bottom: var(--space-8);
  line-height: 1.7;
}

.hero__actions {
  display: flex;
  gap: var(--space-4);
  flex-wrap: wrap;
}

/* ============================================
   Buttons
   ============================================ */

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  text-decoration: none;
  border-radius: var(--radius-sm);
  transition: all 0.25s ease;
  cursor: pointer;
}

.btn--primary {
  background: var(--color-primary);
  color: var(--color-bg);
  border: 1px solid var(--color-primary);
}

.btn--primary:hover {
  background: var(--color-primary-hover);
  box-shadow: 0 0 24px rgba(0, 201, 214, 0.3);
}

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

.btn--outline:hover {
  border-color: var(--color-text-muted);
  background: var(--color-surface);
}

/* ============================================
   Stats Bar
   ============================================ */

.stats {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border-subtle);
  border-bottom: 1px solid var(--color-border-subtle);
  padding: var(--space-10) 0;
}

.stats__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-8);
  text-align: center;
}

.stats__item {
  position: relative;
}

.stats__item:not(:last-child)::after {
  content: '';
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  height: 40px;
  width: 1px;
  background: var(--color-border);
}

.stats__number {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 800;
  color: var(--color-primary);
  letter-spacing: -0.02em;
}

.stats__label {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-top: var(--space-1);
}

/* ============================================
   About Section
   ============================================ */

.about {
  padding: clamp(var(--space-16), 8vw, var(--space-32)) 0;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-4);
}

.section-tag::before {
  content: '';
  display: block;
  width: 24px;
  height: 1px;
  background: var(--color-primary);
}

.section-title {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-6);
  letter-spacing: -0.02em;
}

.about__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-12);
  align-items: center;
  margin-top: var(--space-10);
}

.about__text p {
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
  line-height: 1.8;
}

.about__image {
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--color-border-subtle);
}

.about__image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  aspect-ratio: 4/3;
}

/* ============================================
   Products Section
   ============================================ */

.products {
  padding: clamp(var(--space-16), 8vw, var(--space-32)) 0;
  background: var(--color-surface);
}

.products__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-6);
  margin-top: var(--space-10);
}

.product-card {
  background: var(--color-surface-2);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all 0.3s ease;
}

.product-card:hover {
  border-color: var(--color-primary);
  box-shadow: 0 0 32px var(--color-primary-glow);
  transform: translateY(-4px);
}

.product-card__image {
  aspect-ratio: 16/10;
  overflow: hidden;
}

.product-card__image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

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

.product-card__body {
  padding: var(--space-6);
}

.product-card__icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-primary-dim);
  border-radius: var(--radius-md);
  color: var(--color-primary);
  margin-bottom: var(--space-4);
}

.product-card__title {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-3);
}

.product-card__desc {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.7;
}

/* ============================================
   Features Strip
   ============================================ */

.features {
  padding: clamp(var(--space-12), 6vw, var(--space-20)) 0;
  border-top: 1px solid var(--color-border-subtle);
  border-bottom: 1px solid var(--color-border-subtle);
}

.features__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-8);
}

.feature {
  text-align: center;
}

.feature__icon {
  width: 48px;
  height: 48px;
  margin: 0 auto var(--space-4);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-primary);
}

.feature__title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--text-sm);
  color: var(--color-text);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-2);
}

.feature__desc {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  line-height: 1.6;
}

/* ============================================
   Corporate Info / Contact
   ============================================ */

.contact {
  padding: clamp(var(--space-16), 8vw, var(--space-32)) 0;
}

.contact__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-12);
  margin-top: var(--space-10);
}

.contact__info {
  display: flex;
  flex-direction: column;
  gap: var(--space-8);
}

.info-block {
  padding: var(--space-6);
  background: var(--color-surface);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
}

.info-block__label {
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-3);
}

.info-block__content {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.8;
}

.info-block__content a {
  color: var(--color-text);
  text-decoration: none;
}

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

.contact__corporate {
  padding: var(--space-8);
  background: var(--color-surface);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
}

.corporate-detail {
  display: flex;
  justify-content: space-between;
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--color-border-subtle);
  font-size: var(--text-sm);
}

.corporate-detail:last-child {
  border-bottom: none;
}

.corporate-detail__label {
  color: var(--color-text-faint);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-size: var(--text-xs);
  font-weight: 500;
}

.corporate-detail__value {
  color: var(--color-text-muted);
  text-align: right;
}

/* ============================================
   Footer
   ============================================ */

.footer {
  padding: var(--space-8) 0;
  border-top: 1px solid var(--color-border-subtle);
  background: var(--color-surface);
}

.footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.footer__copy {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
}

.footer__legal {
  display: flex;
  gap: var(--space-6);
}

.footer__legal a {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  text-decoration: none;
}

.footer__legal a:hover {
  color: var(--color-text-muted);
}

/* ============================================
   Scroll Animations
   ============================================ */

.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

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

@media (max-width: 1024px) {
  .products__grid {
    grid-template-columns: 1fr 1fr;
  }
  .features__grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-6);
  }
}

@media (max-width: 768px) {
  .header__nav {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(10, 11, 13, 0.97);
    backdrop-filter: blur(20px);
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: var(--space-8);
    z-index: 200;
  }

  .header__nav.open {
    display: flex;
  }

  .header__nav a {
    font-size: var(--text-lg);
  }

  .mobile-menu-btn {
    display: flex;
    z-index: 300;
  }

  .mobile-menu-btn.open span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }
  .mobile-menu-btn.open span:nth-child(2) {
    opacity: 0;
  }
  .mobile-menu-btn.open span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
  }

  .hero__content {
    padding: var(--space-10) 0;
  }

  .hero__title {
    font-size: var(--text-2xl);
  }

  .stats__grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-6);
  }

  .stats__item:not(:last-child)::after {
    display: none;
  }

  .about__grid {
    grid-template-columns: 1fr;
    gap: var(--space-8);
  }

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

  .features__grid {
    grid-template-columns: 1fr;
    gap: var(--space-8);
  }

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

  .footer__inner {
    flex-direction: column;
    gap: var(--space-4);
    text-align: center;
  }

  .hero__actions {
    flex-direction: column;
  }

  .btn {
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .container {
    padding-inline: var(--space-4);
  }

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