/* =====================================================
   DISEN Building Materials Co., Ltd. - Main Stylesheet
   ===================================================== */

/* ---- CSS Variables ---- */
:root {
  --gold: #c9a84c;
  --gold-light: #e2c06a;
  --gold-dark: #a07830;
  --dark: #1a1a1a;
  --dark-2: #2a2a2a;
  --dark-3: #333;
  --text: #444;
  --text-light: #666;
  --bg-light: #f7f5f0;
  --bg-white: #ffffff;
  --border: #e0d8cc;
  --radius: 8px;
  --radius-lg: 16px;
  --shadow: 0 4px 20px rgba(0,0,0,0.10);
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.15);
  --transition: all 0.3s ease;
  --font-heading: 'Montserrat', sans-serif;
  --font-body: 'Open Sans', sans-serif;
  --header-h: 80px;
}

/* ---- Reset & Base ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-body);
  color: var(--text);
  background: var(--bg-white);
  line-height: 1.7;
  overflow-x: hidden;
}
img { max-width: 100%; height: auto; display: block; }
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
button { cursor: pointer; font-family: var(--font-body); border: none; background: none; }

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 90px 0;
}

/* ---- Typography ---- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  line-height: 1.25;
  color: var(--dark);
}

.section-tag {
  display: inline-block;
  background: linear-gradient(135deg, var(--gold), var(--gold-light));
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 2px;
  text-transform: uppercase;
  padding: 5px 16px;
  border-radius: 20px;
  margin-bottom: 14px;
}

.section-title {
  font-size: clamp(1.8rem, 3vw, 2.6rem);
  font-weight: 800;
  color: var(--dark);
  margin-bottom: 16px;
}
.section-title span { color: var(--gold); }

.section-desc {
  font-size: 1.05rem;
  color: var(--text-light);
  max-width: 620px;
}

.section-header {
  text-align: center;
  margin-bottom: 56px;
}
.section-header .section-desc { margin: 0 auto; }

/* ---- Buttons ---- */
.btn {
  display: inline-block;
  padding: 13px 30px;
  border-radius: var(--radius);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 14px;
  letter-spacing: 0.5px;
  transition: var(--transition);
  white-space: nowrap;
}
.btn-primary {
  background: linear-gradient(135deg, var(--gold), var(--gold-dark));
  color: #fff;
  box-shadow: 0 4px 15px rgba(192,144,72,0.4);
}
.btn-primary:hover {
  background: linear-gradient(135deg, var(--gold-light), var(--gold));
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(192,144,72,0.5);
}
.btn-outline {
  border: 2px solid #fff;
  color: #fff;
}
.btn-outline:hover {
  background: rgba(255,255,255,0.15);
  transform: translateY(-2px);
}
.btn-sm { padding: 8px 20px; font-size: 13px; }
.btn-full { width: 100%; text-align: center; }

/* ============================================================
   HEADER
   ============================================================ */
#header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-h);
  z-index: 1000;
  transition: var(--transition);
  background: transparent;
}
#header.scrolled {
  background: rgba(26,26,26,0.97);
  box-shadow: 0 2px 20px rgba(0,0,0,0.3);
  height: 64px;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo-img {
  height: 56px;
  width: auto;
  filter: drop-shadow(0 2px 8px rgba(0,0,0,0.3));
  transition: var(--transition);
}
#header.scrolled .logo-img { height: 44px; }

/* Nav */
.nav ul {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav > ul > li > a {
  padding: 8px 14px;
  color: rgba(255,255,255,0.92);
  font-family: var(--font-heading);
  font-size: 13.5px;
  font-weight: 600;
  letter-spacing: 0.3px;
  transition: var(--transition);
  border-radius: 6px;
  white-space: nowrap;
}
.nav > ul > li > a:hover,
.nav > ul > li > a.active {
  color: var(--gold-light);
  background: rgba(255,255,255,0.08);
}

/* Dropdown */
.has-dropdown { position: relative; }
.dropdown {
  position: absolute;
  top: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  background: var(--dark-2);
  border: 1px solid rgba(201,168,76,0.3);
  border-radius: var(--radius);
  min-width: 220px;
  padding: 8px 0;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
}
.has-dropdown:hover .dropdown {
  opacity: 1;
  visibility: visible;
  top: calc(100% + 4px);
}
.dropdown li a {
  display: block;
  padding: 9px 20px;
  color: rgba(255,255,255,0.82);
  font-size: 13px;
  transition: var(--transition);
}
.dropdown li a:hover {
  color: var(--gold-light);
  background: rgba(201,168,76,0.1);
  padding-left: 26px;
}

.arrow { font-size: 10px; margin-left: 3px; }

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 6px;
}
.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: var(--transition);
}

/* ============================================================
   HERO
   ============================================================ */
.hero {
  position: relative;
  height: 100vh;
  min-height: 600px;
  overflow: hidden;
}

.hero-slider { width: 100%; height: 100%; }

.slide {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  opacity: 0;
  transition: opacity 1s ease;
  background-size: cover;
  background-position: center;
}
.slide.active { opacity: 1; z-index: 1; }

.slide-1 {
  background-image:
    linear-gradient(135deg, rgba(20,15,5,0.65) 40%, rgba(80,55,10,0.35) 100%),
    url('images/slider/slide1.jpg');
}
.slide-2 {
  background-image:
    linear-gradient(135deg, rgba(10,20,10,0.65) 40%, rgba(30,60,20,0.35) 100%),
    url('images/slider/slide2.png');
}
.slide-3 {
  background-image:
    linear-gradient(135deg, rgba(15,10,25,0.65) 40%, rgba(50,30,10,0.35) 100%),
    url('images/slider/slide3.jpg');
}
.slide-4 {
  background-image:
    linear-gradient(135deg, rgba(10,15,20,0.65) 40%, rgba(30,40,50,0.35) 100%),
    url('images/slider/slide4.jpg');
}
.slide-5 {
  background-image:
    linear-gradient(135deg, rgba(25,15,5,0.65) 40%, rgba(60,40,15,0.35) 100%),
    url('images/slider/slide5.jpg');
}
.slide-6 {
  background-image:
    linear-gradient(135deg, rgba(15,20,25,0.65) 40%, rgba(40,50,60,0.35) 100%),
    url('images/slider/slide6.jpg');
}
.slide-7 {
  background-image:
    linear-gradient(135deg, rgba(20,15,10,0.65) 40%, rgba(50,40,30,0.35) 100%),
    url('images/slider/slide7.jpg');
}

.slide-content {
  position: relative;
  z-index: 2;
  max-width: 680px;
  padding: 0 40px;
  margin-left: 80px;
  animation: slideIn 0.8s ease forwards;
}
@keyframes slideIn {
  from { opacity: 0; transform: translateY(30px); }
  to   { opacity: 1; transform: translateY(0); }
}

.slide-content h1 {
  font-size: clamp(2.2rem, 5vw, 3.8rem);
  font-weight: 800;
  color: #fff;
  line-height: 1.15;
  margin-bottom: 20px;
}
.slide-content h1 span {
  color: var(--gold-light);
}
.slide-content p {
  font-size: clamp(1rem, 1.8vw, 1.15rem);
  color: rgba(255,255,255,0.88);
  margin-bottom: 36px;
  line-height: 1.7;
}
.hero-btns { display: flex; gap: 16px; flex-wrap: wrap; }

/* Slider Controls */
.slider-controls {
  position: absolute;
  bottom: 36px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10;
  display: flex;
  align-items: center;
  gap: 16px;
}
.prev-btn, .next-btn {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 2px solid rgba(255,255,255,0.5);
  color: #fff;
  font-size: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}
.prev-btn:hover, .next-btn:hover {
  background: var(--gold);
  border-color: var(--gold);
}
.dots { display: flex; gap: 8px; }
.dot {
  width: 10px; height: 10px;
  border-radius: 50%;
  background: rgba(255,255,255,0.45);
  cursor: pointer;
  transition: var(--transition);
}
.dot.active {
  background: var(--gold-light);
  width: 28px;
  border-radius: 5px;
}

/* ============================================================
   STATS BAR
   ============================================================ */
.stats-bar {
  background: linear-gradient(135deg, var(--dark) 0%, #2c2200 100%);
  padding: 48px 0;
}
.stats-bar .container {
  display: flex;
  justify-content: space-around;
  flex-wrap: wrap;
  gap: 32px;
}
.stat-item { text-align: center; }
.stat-number {
  font-family: var(--font-heading);
  font-size: clamp(2.4rem, 4vw, 3.4rem);
  font-weight: 800;
  color: var(--gold-light);
  line-height: 1;
  margin-bottom: 8px;
}
.stat-number::after { content: '+'; }
.stat-label {
  font-size: 13px;
  color: rgba(255,255,255,0.7);
  font-weight: 500;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

/* ============================================================
   ABOUT
   ============================================================ */
.about { background: var(--bg-white); }

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.about-image {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}
.about-image img {
  width: 100%;
  height: 520px;
  object-fit: cover;
  transition: transform 0.6s ease;
}
.about-image:hover img { transform: scale(1.04); }

.about-badge {
  position: absolute;
  bottom: 28px;
  right: 28px;
  background: linear-gradient(135deg, var(--gold), var(--gold-dark));
  color: #fff;
  padding: 16px 22px;
  border-radius: var(--radius);
  text-align: center;
  box-shadow: var(--shadow);
}
.badge-year {
  display: block;
  font-family: var(--font-heading);
  font-size: 18px;
  font-weight: 800;
  margin-bottom: 4px;
}
.badge-text {
  display: block;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 1px;
  text-transform: uppercase;
  opacity: 0.9;
}

.about-content { padding-left: 16px; }
.about-content p {
  margin-bottom: 16px;
  color: var(--text);
  font-size: 1rem;
}
.about-features {
  margin: 28px 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.feature-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  font-size: 0.95rem;
  color: var(--text);
}
.feature-icon { font-size: 16px; flex-shrink: 0; margin-top: 3px; }

/* ============================================================
   PRODUCTS
   ============================================================ */
.products { background: var(--bg-light); }

.product-tabs {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 44px;
}
.tab-btn {
  padding: 9px 24px;
  border-radius: 24px;
  border: 2px solid var(--border);
  font-family: var(--font-heading);
  font-size: 13px;
  font-weight: 600;
  color: var(--text-light);
  transition: var(--transition);
  background: var(--bg-white);
}
.tab-btn:hover, .tab-btn.active {
  background: linear-gradient(135deg, var(--gold), var(--gold-dark));
  border-color: var(--gold);
  color: #fff;
  box-shadow: 0 4px 12px rgba(192,144,72,0.35);
}

.products-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.product-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: var(--transition);
  position: relative;
}
.product-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

/* Product card as clickable link */
.product-card-link {
  text-decoration: none;
  color: inherit;
  display: block;
}

.product-img-wrap {
  position: relative;
  overflow: hidden;
  height: 220px;
}
.product-img-wrap img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}
.product-card:hover .product-img-wrap img { transform: scale(1.08); }

.product-overlay {
  position: absolute;
  inset: 0;
  background: rgba(26,16,0,0.55);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: var(--transition);
}
.product-card:hover .product-overlay { opacity: 1; }

.product-info { padding: 22px 24px 26px; }
.product-info h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--dark);
}
.product-info p {
  font-size: 0.9rem;
  color: var(--text-light);
  line-height: 1.6;
  margin-bottom: 16px;
}
.product-specs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 18px;
}
.product-specs span {
  background: var(--bg-light);
  border: 1px solid var(--border);
  color: var(--text);
  font-size: 11.5px;
  padding: 3px 10px;
  border-radius: 12px;
  font-weight: 500;
}
.product-link {
  color: var(--gold-dark);
  font-weight: 700;
  font-size: 13.5px;
  font-family: var(--font-heading);
  transition: var(--transition);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}
.product-link:hover {
  color: var(--gold);
  letter-spacing: 0.3px;
}

/* Product image gallery row (3 thumbnails inside card) */
.product-img-gallery {
  display: flex;
  gap: 6px;
  margin-bottom: 14px;
  margin-top: -4px;
}
.product-img-gallery img {
  flex: 1;
  height: 64px;
  object-fit: cover;
  border-radius: 6px;
  border: 1.5px solid var(--border);
  cursor: pointer;
  transition: var(--transition);
  opacity: 0.85;
}
.product-img-gallery img:hover {
  opacity: 1;
  border-color: var(--gold);
  transform: translateY(-2px);
}

/* Core Product badge */
.product-badge {
  position: absolute;
  top: 12px;
  left: 12px;
  background: var(--gold);
  color: var(--dark);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 11px;
  padding: 3px 10px;
  border-radius: 20px;
  letter-spacing: 0.4px;
  z-index: 2;
  text-transform: uppercase;
}

/* ============================================================
   ADVANTAGES
   ============================================================ */
.advantages { background: var(--dark); }
.advantages .section-title { color: #fff; }
.advantages .section-desc { color: rgba(255,255,255,0.65); }
.advantages .section-tag {
  background: rgba(201,168,76,0.2);
  border: 1px solid rgba(201,168,76,0.4);
  color: var(--gold-light);
}

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

.adv-card {
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(201,168,76,0.15);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  transition: var(--transition);
}
.adv-card:hover {
  background: rgba(201,168,76,0.08);
  border-color: rgba(201,168,76,0.4);
  transform: translateY(-4px);
}

.adv-icon {
  width: 56px;
  height: 56px;
  color: var(--gold-light);
  margin-bottom: 20px;
}
.adv-card h3 {
  color: #fff;
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 12px;
}
.adv-card p {
  color: rgba(255,255,255,0.6);
  font-size: 0.9rem;
  line-height: 1.65;
}

/* ============================================================
   MARKETS
   ============================================================ */
.markets { background: var(--bg-light); }

.markets-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 16px;
  margin-bottom: 48px;
}

.market-item {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 12px;
  text-align: center;
  transition: var(--transition);
  box-shadow: var(--shadow);
}
.market-item:hover {
  border-color: var(--gold);
  transform: translateY(-3px);
  box-shadow: 0 6px 24px rgba(192,144,72,0.2);
}
.market-flag {
  font-size: 32px;
  line-height: 1;
  margin-bottom: 8px;
}
.market-item span {
  font-size: 12px;
  font-weight: 600;
  color: var(--text);
  font-family: var(--font-heading);
}
.market-more {
  background: linear-gradient(135deg, var(--gold), var(--gold-dark));
  border-color: var(--gold);
}
.market-more span { color: #fff; }

.markets-cta {
  text-align: center;
  background: var(--dark);
  border-radius: var(--radius-lg);
  padding: 44px;
}
.markets-cta p {
  color: rgba(255,255,255,0.85);
  font-size: 1.1rem;
  font-family: var(--font-heading);
  font-weight: 600;
  margin-bottom: 20px;
}

/* ============================================================
   PROCESS
   ============================================================ */
.process {
  background: var(--bg-white);
  border-top: 1px solid var(--border);
}
.process-steps {
  display: flex;
  align-items: stretch;
  gap: 0;
  overflow-x: auto;
  padding-bottom: 8px;
}
.step {
  flex: 1;
  min-width: 160px;
  text-align: center;
  padding: 32px 20px;
  background: var(--bg-light);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: var(--transition);
}
.step:hover {
  background: linear-gradient(135deg, #fff9ee, #fff4d6);
  border-color: var(--gold);
  transform: translateY(-3px);
}
.step-num {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 800;
  color: var(--gold);
  margin-bottom: 12px;
  opacity: 0.85;
}
.step-content h4 {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--dark);
}
.step-content p {
  font-size: 0.85rem;
  color: var(--text-light);
  line-height: 1.55;
}
.step-arrow {
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  color: var(--gold);
  padding: 0 8px;
  flex-shrink: 0;
}

/* ============================================================
   CONTACT
   ============================================================ */
.contact {
  background: linear-gradient(135deg, #f9f7f4 0%, #f0ece4 100%);
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: start;
}

/* Form */
.contact-form-wrap {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 40px;
  box-shadow: var(--shadow);
}
.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
.form-group {
  margin-bottom: 20px;
}
.form-group label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  color: var(--dark);
  margin-bottom: 7px;
  font-family: var(--font-heading);
}
.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 11px 14px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  font-family: var(--font-body);
  font-size: 14px;
  color: var(--text);
  background: #fdfcfb;
  transition: var(--transition);
  outline: none;
}
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  border-color: var(--gold);
  background: #fff;
  box-shadow: 0 0 0 3px rgba(201,168,76,0.15);
}
.form-group textarea { resize: vertical; }

.form-success {
  display: none;
  margin-top: 14px;
  padding: 12px 16px;
  background: #e8f5e9;
  border-radius: var(--radius);
  color: #2e7d32;
  font-weight: 600;
  font-size: 14px;
}

/* Contact Info */
.contact-info {
  display: flex;
  flex-direction: column;
  gap: 20px;
  padding-top: 8px;
}
.info-card {
  display: flex;
  align-items: flex-start;
  gap: 18px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 22px;
  transition: var(--transition);
}
.info-card:hover {
  border-color: var(--gold);
  box-shadow: 0 4px 16px rgba(192,144,72,0.12);
}
.info-icon {
  font-size: 24px;
  flex-shrink: 0;
  margin-top: 2px;
}
.info-card h4 {
  font-size: 13px;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 5px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.info-card p {
  font-size: 14px;
  color: var(--text);
  line-height: 1.6;
}

.certifications {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
}
.certifications h4 {
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--dark);
  margin-bottom: 14px;
}
.cert-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.cert-badge {
  background: linear-gradient(135deg, var(--gold), var(--gold-dark));
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  padding: 5px 14px;
  border-radius: 14px;
  font-family: var(--font-heading);
  letter-spacing: 0.5px;
}

/* ============================================================
   FOOTER
   ============================================================ */
.footer {
  background: var(--dark);
  padding: 64px 0 0;
  color: rgba(255,255,255,0.7);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 40px;
  padding-bottom: 48px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer-logo {
  height: 60px;
  width: auto;
  margin-bottom: 18px;
  filter: brightness(1.2);
}
.footer-brand p {
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 20px;
  max-width: 280px;
}
.social-links {
  display: flex;
  gap: 12px;
}
.social-links a {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 1px solid rgba(255,255,255,0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255,255,255,0.7);
  transition: var(--transition);
}
.social-links a:hover {
  background: var(--gold);
  border-color: var(--gold);
  color: #fff;
}
.social-links svg { width: 16px; height: 16px; }

.footer-col h4 {
  color: #fff;
  font-family: var(--font-heading);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 18px;
}
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a {
  color: rgba(255,255,255,0.6);
  font-size: 14px;
  transition: var(--transition);
}
.footer-col ul li a:hover {
  color: var(--gold-light);
  padding-left: 4px;
}
.footer-col p {
  font-size: 14px;
  margin-bottom: 8px;
  line-height: 1.5;
}

.footer-bottom {
  padding: 22px 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
  font-size: 13px;
  color: rgba(255,255,255,0.45);
}

/* ============================================================
   BACK TO TOP
   ============================================================ */
.back-to-top {
  position: fixed;
  bottom: 28px;
  right: 28px;
  width: 46px;
  height: 46px;
  background: linear-gradient(135deg, var(--gold), var(--gold-dark));
  color: #fff;
  border-radius: 50%;
  font-size: 22px;
  line-height: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 16px rgba(0,0,0,0.25);
  opacity: 0;
  transform: translateY(10px);
  transition: var(--transition);
  z-index: 500;
}
.back-to-top.visible {
  opacity: 1;
  transform: translateY(0);
}
.back-to-top:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(0,0,0,0.3);
}

/* ============================================================
   DATA-AOS ANIMATIONS
   ============================================================ */
[data-aos] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
[data-aos].aos-animate {
  opacity: 1;
  transform: translateY(0);
}
[data-aos][data-aos-delay="100"] { transition-delay: 0.1s; }
[data-aos][data-aos-delay="200"] { transition-delay: 0.2s; }
[data-aos="fade-right"] { transform: translateX(-24px); }
[data-aos="fade-right"].aos-animate { transform: translateX(0); }
[data-aos="fade-left"] { transform: translateX(24px); }
[data-aos="fade-left"].aos-animate { transform: translateX(0); }

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 1024px) {
  .about-grid { grid-template-columns: 1fr; }
  .about-image img { height: 380px; }
  .adv-grid { grid-template-columns: repeat(2, 1fr); }
  .products-grid { grid-template-columns: repeat(2, 1fr); }
  .markets-grid { grid-template-columns: repeat(4, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  :root { --header-h: 64px; }
  .section { padding: 64px 0; }
  .nav { 
    display: none; 
    position: absolute;
    top: var(--header-h);
    left: 0; right: 0;
    background: rgba(26,26,26,0.97);
    padding: 16px;
    border-top: 1px solid rgba(201,168,76,0.3);
  }
  .nav.open { display: block; }
  .nav ul { flex-direction: column; gap: 0; }
  .nav > ul > li > a { display: block; padding: 12px 16px; }
  .dropdown { position: static; opacity: 1; visibility: visible; transform: none; background: rgba(255,255,255,0.05); margin-top: 0; }
  .hamburger { display: flex; }
  .slide-content { margin-left: 20px; padding: 0 20px; }
  .slide-content h1 { font-size: clamp(1.8rem, 6vw, 2.8rem); }
  .process-steps { flex-direction: column; }
  .step-arrow { transform: rotate(90deg); padding: 4px 0; align-self: center; }
  .adv-grid { grid-template-columns: 1fr; }
  .products-grid { grid-template-columns: 1fr; }
  .markets-grid { grid-template-columns: repeat(3, 1fr); }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; text-align: center; }
  .form-row { grid-template-columns: 1fr; }
  .stats-bar .container { flex-direction: column; align-items: center; gap: 24px; }
}

@media (max-width: 480px) {
  .markets-grid { grid-template-columns: repeat(2, 1fr); }
  .contact-form-wrap { padding: 24px; }
  .hero-btns { flex-direction: column; }
  .btn { text-align: center; }
}