/* ==========================================================================
   CDHT Industries — Design Tokens
   ========================================================================== */
:root {
  --color-primary: #12151B;
  --color-primary-light: #1C2028;
  --color-on-primary: #FFFFFF;
  --color-secondary: #4B5563;
  --color-accent: #1A3FB0;
  --color-accent-dark: #15328C;
  --color-on-accent: #FFFFFF;
  --color-background: #F7F8FA;
  --color-surface: #FFFFFF;
  --color-foreground: #12151B;
  --color-muted: #5B6470;
  --color-muted-bg: #EEF1F5;
  --color-border: #E2E5EA;
  --color-ring: #1A3FB0;

  --font-heading: 'Oswald', system-ui, -apple-system, 'Segoe UI', sans-serif;
  --font-body: 'Source Sans 3', system-ui, -apple-system, 'Segoe UI', sans-serif;

  --space-1: 4px;
  --space-2: 8px;
  --space-3: 16px;
  --space-4: 24px;
  --space-5: 32px;
  --space-6: 44px;
  --space-7: 58px;
  --space-8: 88px;

  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;

  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 8px 24px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 20px 48px rgba(15, 23, 42, 0.14);

  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --dur-fast: 180ms;
  --dur-base: 280ms;

  --container: 1200px;
}

/* ==========================================================================
   Reset
   ========================================================================== */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}
#products, #about, #quality, #contact {
  scroll-margin-top: 92px;
}
body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--color-foreground);
  background: var(--color-background);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul, ol { margin: 0; padding: 0; list-style: none; }
button { font: inherit; cursor: pointer; }
h1, h2, h3, h4 {
  font-family: var(--font-heading);
  color: var(--color-foreground);
  margin: 0;
  line-height: 1.15;
  letter-spacing: -0.01em;
}
p { margin: 0; }

.wrap {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

/* Focus visibility */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--color-accent);
  color: var(--color-on-accent);
  padding: 10px 16px;
  z-index: 1000;
  border-radius: 0 0 var(--radius-sm) 0;
}
.skip-link:focus {
  left: 0;
}

/* ==========================================================================
   Buttons
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 24px;
  border-radius: var(--radius-sm);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 15px;
  border: 1px solid transparent;
  transition: transform var(--dur-fast) var(--ease-out),
              background-color var(--dur-fast) var(--ease-out),
              box-shadow var(--dur-fast) var(--ease-out),
              border-color var(--dur-fast) var(--ease-out);
  cursor: pointer;
  min-height: 44px;
}
.btn-primary {
  background: var(--color-accent);
  color: var(--color-on-accent);
}
.btn-primary:hover {
  background: var(--color-accent-dark);
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}
.btn-sm { padding: 11px 16px; font-size: 14px; min-height: 44px; }
.btn-lg { padding: 15px 30px; font-size: 16px; }
.btn-block { width: 100%; }
/* ==========================================================================
   Header
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(247, 248, 250, 0.88);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur-base) var(--ease-out),
              box-shadow var(--dur-base) var(--ease-out);
}
.site-header.is-scrolled {
  border-bottom-color: var(--color-border);
  box-shadow: var(--shadow-sm);
}
.header-topbar {
  height: 3px;
  background: linear-gradient(90deg, var(--color-accent) 0%, var(--color-accent-dark) 100%);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  height: 76px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}
.logo-text {
  font-family: var(--font-heading);
  font-size: 15px;
  letter-spacing: 0.04em;
  color: var(--color-foreground);
}
.logo-text strong { font-weight: 700; }

.main-nav {
  display: flex;
  gap: var(--space-5);
}
.main-nav a {
  font-family: var(--font-heading);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-secondary);
  position: relative;
  padding: 4px 0;
  transition: color var(--dur-fast) var(--ease-out);
}
.main-nav a::after {
  content: "";
  position: absolute;
  left: 0; bottom: -2px;
  width: 0;
  height: 2px;
  background: var(--color-accent);
  transition: width var(--dur-base) var(--ease-out);
}
.main-nav a:hover {
  color: var(--color-foreground);
}
.main-nav a:hover::after {
  width: 100%;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  background: transparent;
  border: none;
  padding: 0;
}
.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-foreground);
  margin: 0 auto;
  transition: transform var(--dur-base) var(--ease-out), opacity var(--dur-fast) var(--ease-out);
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ==========================================================================
   Hero
   ========================================================================== */
.hero {
  position: relative;
  overflow: hidden;
  background: var(--color-primary);
  padding: 72px 0 66px;
}
.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.hero-svg { width: 100%; height: 100%; }
.hero-streaks {
  position: absolute;
  inset: 0;
  background:
    repeating-linear-gradient(115deg, rgba(62,123,250,0.14) 0px, rgba(62,123,250,0.14) 2px, transparent 2px, transparent 46px),
    linear-gradient(115deg, rgba(18,21,27,0) 0%, rgba(62,123,250,0.18) 45%, rgba(18,21,27,0) 75%);
  filter: blur(22px);
  mix-blend-mode: screen;
  opacity: 0.75;
}
.hero-inner {
  position: relative;
  z-index: 1;
  max-width: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-6);
}
.hero-text {
  max-width: 620px;
  flex: 1 1 480px;
  margin-left: 64px;
}
.eyebrow {
  font-family: var(--font-heading);
  font-size: 19.5px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: var(--space-3);
}
.eyebrow-light { color: #A9C6FF; }
.hero h1 {
  color: #fff;
  font-size: clamp(2.1rem, 4.4vw, 3.4rem);
  font-weight: 700;
  margin-bottom: var(--space-4);
}
.hero-rule {
  width: 110px;
  height: 4px;
  background: var(--color-accent);
  margin-bottom: var(--space-4);
}
.hero-sub {
  color: #CBD5E1;
  font-size: 17px;
  line-height: 1.65;
  margin-bottom: var(--space-5);
  max-width: 58ch;
}

/* ==========================================================================
   Hero gallery
   ========================================================================== */
.hero-gallery {
  position: relative;
  flex: 0 0 450px;
  width: 450px;
  margin-right: 64px;
}
.hero-gallery-frame {
  position: relative;
  width: 100%;
  aspect-ratio: 4 / 3;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--color-surface);
  border: 1px solid rgba(255, 255, 255, 0.1);
  box-shadow: var(--shadow-lg);
}
.hero-gallery-img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: contain;
  background: var(--color-surface);
  padding: 28px;
  opacity: 0;
  transition: opacity var(--dur-base) var(--ease-out);
}
.hero-gallery-img.is-active {
  opacity: 1;
}
.hero-gallery-arrow {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.92);
  border: none;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-foreground);
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: background-color var(--dur-fast) var(--ease-out);
}
.hero-gallery-arrow:hover {
  background: #fff;
  color: var(--color-accent);
}
.hero-gallery-prev { left: 12px; }
.hero-gallery-next { right: 12px; }
.hero-gallery-dots {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-top: var(--space-3);
}
.hero-gallery-dot {
  width: 8px;
  height: 8px;
  padding: 0;
  border: none;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.28);
  cursor: pointer;
  transition: background-color var(--dur-fast) var(--ease-out), width var(--dur-fast) var(--ease-out);
}
.hero-gallery-dot.is-active {
  width: 20px;
  background: var(--color-accent);
}

/* ==========================================================================
   Filter tabs
   ========================================================================== */
.filter-tabs {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-bottom: var(--space-6);
}
.filter-tab {
  font-family: var(--font-heading);
  font-size: 13.5px;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--color-secondary);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  padding: 10px 20px;
  min-height: 44px;
  transition: background-color var(--dur-fast) var(--ease-out),
              color var(--dur-fast) var(--ease-out),
              border-color var(--dur-fast) var(--ease-out);
}
.filter-tab:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}
.filter-tab.is-active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #fff;
}
.card.is-hidden { display: none; }

/* ==========================================================================
   Sections
   ========================================================================== */
.section {
  padding: 64px 0;
}
.section-head {
  max-width: 640px;
  margin: 0 auto var(--space-6);
  text-align: center;
}
.section-head h2 {
  font-size: clamp(1.7rem, 3vw, 2.3rem);
  margin-bottom: var(--space-3);
}
.section-sub {
  color: var(--color-muted);
  font-size: 16px;
  margin-top: var(--space-3);
}

/* ==========================================================================
   Product cards
   ========================================================================== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-4);
}
.card {
  display: block;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  transition: transform var(--dur-base) var(--ease-out),
              box-shadow var(--dur-base) var(--ease-out),
              border-color var(--dur-base) var(--ease-out);
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}
.card h3 {
  font-size: 1.15rem;
  margin-bottom: var(--space-2);
}
.card p {
  color: var(--color-muted);
  font-size: 14.5px;
  line-height: 1.6;
}

/* ==========================================================================
   About banner
   ========================================================================== */
.about-banner {
  padding: 64px 0;
}
.about-banner-inner {
  max-width: 720px;
  margin: 0 auto;
  text-align: center;
}
.about-banner-inner .hero-rule {
  margin-left: auto;
  margin-right: auto;
}
.about-banner-inner p:not(.eyebrow) {
  color: var(--color-muted);
  font-size: 17px;
  line-height: 1.7;
}

/* ==========================================================================
   Timeline
   ========================================================================== */
.timeline {
  counter-reset: step;
  max-width: 760px;
  margin: 0 auto;
  position: relative;
}
.timeline::before {
  content: "";
  position: absolute;
  left: 23px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--color-border);
}
.timeline-step {
  display: flex;
  gap: var(--space-4);
  position: relative;
  padding-bottom: var(--space-6);
}
.timeline-step:last-child { padding-bottom: 0; }
.timeline-marker {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--color-primary);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 16px;
  position: relative;
  z-index: 1;
}
.timeline-content h3 {
  font-size: 1.1rem;
  margin-bottom: 6px;
}
.timeline-content p {
  color: var(--color-muted);
  font-size: 14.5px;
  line-height: 1.6;
  max-width: 52ch;
}

/* ==========================================================================
   Contact
   ========================================================================== */
.contact-card {
  max-width: 560px;
  margin: 0 auto;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-2) var(--space-6);
  box-shadow: var(--shadow-sm);
}
.contact-row {
  padding: var(--space-4) 0;
}
.contact-row + .contact-row {
  border-top: 1px solid var(--color-border);
}
.contact-row-text {
  display: flex;
  flex-direction: column;
  gap: 2px;
  text-align: left;
}
.contact-row-text a,
.contact-row-text span {
  color: var(--color-muted);
  font-size: 15px;
}
.contact-row-text a {
  transition: color var(--dur-fast) var(--ease-out);
}
.contact-row-text a:hover {
  color: var(--color-accent);
}

/* ==========================================================================
   Category page
   ========================================================================== */
.section-muted {
  background: var(--color-muted-bg);
}
.category-page-intro {
  padding: 56px 0 40px;
  text-align: center;
  border-bottom: 1px solid var(--color-border);
}
.category-breadcrumb {
  font-family: var(--font-heading);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: var(--space-3);
}
.category-breadcrumb a {
  color: var(--color-accent);
  transition: color var(--dur-fast) var(--ease-out);
}
.category-breadcrumb a:hover {
  color: var(--color-accent-dark);
  text-decoration: underline;
}
.category-page-intro h1 {
  font-size: clamp(1.8rem, 3.4vw, 2.6rem);
}
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--space-4);
}
.gallery-grid img {
  display: block;
  width: 100%;
  height: 320px;
  object-fit: contain;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-4);
}
.gallery-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  height: 320px;
  background: var(--color-surface);
  border: 1px dashed var(--color-border);
  border-radius: var(--radius-lg);
  color: var(--color-muted);
}
.gallery-placeholder svg {
  width: 40px;
  height: 40px;
  color: var(--color-muted);
}
.gallery-placeholder span {
  font-family: var(--font-heading);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.02em;
}
.table-scroll {
  overflow-x: auto;
}
.catalog-table {
  width: 100%;
  min-width: 560px;
  border-collapse: collapse;
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}
.catalog-table th,
.catalog-table td {
  text-align: left;
  padding: 14px 20px;
  font-size: 14.5px;
  border-bottom: 1px solid var(--color-border);
}
.catalog-table th {
  font-family: var(--font-heading);
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-secondary);
  background: var(--color-muted-bg);
}
.catalog-table td {
  color: var(--color-secondary);
}
.catalog-table tbody tr:last-child td {
  border-bottom: none;
}
.catalog-note {
  margin-top: var(--space-4);
  font-size: 14px;
  color: var(--color-muted);
}

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer {
  background: var(--color-primary);
  color: #A7ADB8;
  padding-top: 48px;
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: var(--space-6);
  flex-wrap: wrap;
  padding-bottom: var(--space-6);
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.footer-brand { max-width: 320px; }
.footer-brand .logo-text { color: #fff; }
.footer-brand p { margin-top: var(--space-3); font-size: 14.5px; line-height: 1.6; }
.footer-bottom {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-2);
  padding: var(--space-4) var(--space-4);
  font-size: 13px;
}

/* ==========================================================================
   Scroll reveal
   ========================================================================== */
.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 600ms var(--ease-out), transform 600ms var(--ease-out);
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}
@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }
}

/* ==========================================================================
   Responsive
   ========================================================================== */
@media (max-width: 1024px) {
  .card-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 900px) {
  .hero-inner {
    flex-direction: column;
    align-items: stretch;
  }
  .hero-text { max-width: none; }
  .hero-gallery { width: 100%; flex: none; max-width: 420px; margin: 0 auto; }
}

@media (max-width: 860px) {
  .main-nav {
    position: fixed;
    top: 76px;
    left: 0;
    right: 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    flex-direction: column;
    gap: 0;
    padding: var(--space-2) var(--space-4) var(--space-4);
    transform: translateY(-8px);
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--dur-base) var(--ease-out), transform var(--dur-base) var(--ease-out);
  }
  .main-nav.is-open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }
  .main-nav a {
    padding: 12px 0;
    border-bottom: 1px solid var(--color-border);
  }
  .nav-toggle { display: flex; }
}

@media (max-width: 640px) {
  .hero { padding: 48px 0 42px; }
  .section { padding: 48px 0; }
  .card-grid { grid-template-columns: 1fr; }
  .contact-card { padding: var(--space-2) var(--space-4); }
  .category-page-intro { padding: 40px 0 28px; }
  .gallery-grid img, .gallery-placeholder { height: 240px; }
  .footer-inner { flex-direction: column; }
  .footer-bottom { flex-direction: column; }
}