/* ========== Elecsky RF Store - Global Styles ========== */
/* Design Philosophy: Clean, Professional, Minimalist */

:root {
  --primary: #0a2a4a;
  --primary-light: #1a4a7a;
  --accent: #0080ff;
  --accent-light: #e6f2ff;
  --text-dark: #1a1a1a;
  --text-gray: #666;
  --text-light: #999;
  --bg-light: #f5f7fa;
  --bg-white: #ffffff;
  --border: #e0e0e0;
  --success: #28a745;
  --warning: #ffc107;
  --danger: #dc3545;
  --radius: 8px;
  --shadow: 0 2px 12px rgba(0,0,0,0.08);
  --shadow-hover: 0 4px 20px rgba(0,0,0,0.15);
  --transition: all 0.3s ease;
  --max-width: 1200px;
  --nav-height: 64px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-dark);
  background: var(--bg-white);
  overflow-x: hidden;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: var(--transition);
}

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

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

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* ========== Header & Navigation ========== */
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--bg-white);
  box-shadow: 0 1px 4px rgba(0,0,0,0.06);
}

.header-top {
  background: var(--primary);
  color: #fff;
  font-size: 13px;
  padding: 6px 0;
}

.header-top .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.header-top a {
  color: rgba(255, 255, 255, 0.5);
}

.header-top a:hover {
  color: #fff;
}

/* ========== Language Switcher ========== */
.lang-switcher {
  display: flex;
  align-items: center;
  gap: 2px;
}

.lang-switcher a {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 4px;
  color: rgba(255, 255, 255, 0.5);
  font-size: 13px;
  font-weight: 500;
  text-decoration: none;
  transition: all 0.2s ease;
}

.lang-switcher a:hover {
  background: rgba(255, 255, 255, 0.15);
  color: #fff;
}

.lang-switcher a.active {
  color: #fff;
  font-weight: 700;
}

.lang-switcher .lang-sep {
  color: rgba(255, 255, 255, 0.4);
  font-size: 12px;
  user-select: none;
}

@media (max-width: 768px) {
  .lang-switcher a {
    padding: 2px 8px;
    font-size: 12px;
  }
}

.header-main {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--nav-height);
  padding: 0 20px;
  max-width: var(--max-width);
  margin: 0 auto;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 24px;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: -0.5px;
}

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

.logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 18px;
  font-weight: bold;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 4px;
  align-items: center;
}

.nav-menu > li > a {
  display: block;
  padding: 8px 16px;
  color: var(--text-dark);
  font-weight: 500;
  font-size: 14px;
  border-radius: 6px;
  transition: var(--transition);
}

.nav-menu > li > a:hover,
.nav-menu > li > a.active {
  background: var(--accent-light);
  color: var(--accent);
}

.nav-lang-item {
  display: none;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 24px;
  cursor: pointer;
  color: var(--primary);
}

/* ========== Hero Carousel ========== */
.hero {
  position: relative;
  height: 420px;
  overflow: hidden;
  background: var(--primary);
}

.carousel {
  position: relative;
  height: 100%;
  width: 100%;
}

.carousel-slide {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  transition: opacity 1s ease-in-out;
  display: flex;
  align-items: center;
  justify-content: center;
}

.carousel-slide.active {
  opacity: 1;
}

.carousel-slide .slide-content {
  text-align: center;
  color: #fff;
  max-width: 700px;
  padding: 40px;
  z-index: 2;
}

.carousel-slide .slide-content h2 {
  font-size: 36px;
  font-weight: 700;
  margin-bottom: 16px;
  line-height: 1.3;
  text-shadow: 0 2px 10px rgba(0,0,0,0.3);
}

.carousel-slide .slide-content p {
  font-size: 18px;
  margin-bottom: 24px;
  opacity: 0.9;
}

.carousel-slide .slide-content .btn {
  font-size: 16px;
  padding: 12px 32px;
}

.carousel-btn {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  background: rgba(255,255,255,0.15);
  border: none;
  color: #fff;
  font-size: 28px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  cursor: pointer;
  transition: var(--transition);
  z-index: 3;
  display: flex;
  align-items: center;
  justify-content: center;
}

.carousel-btn:hover {
  background: rgba(255,255,255,0.3);
}

.carousel-btn.prev { left: 20px; }
.carousel-btn.next { right: 20px; }

.carousel-dots {
  position: absolute;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 8px;
  z-index: 3;
}

.carousel-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: rgba(255,255,255,0.4);
  border: none;
  cursor: pointer;
  transition: var(--transition);
}

.carousel-dot.active {
  background: #fff;
  width: 30px;
  border-radius: 5px;
}

/* Slide backgrounds */
.slide-1 { background: linear-gradient(135deg, #0a2a4a 0%, #1a4a7a 50%, #0080ff 100%); }
.slide-2 { background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%); }
.slide-3 { background: linear-gradient(135deg, #0f4c5c 0%, #1a6a7a 50%, #2a9ab0 100%); }

/* ========== Buttons ========== */
.btn {
  display: inline-block;
  padding: 10px 24px;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  text-align: center;
}

.btn:hover {
  background: var(--primary);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: var(--shadow);
}

.btn-outline {
  background: transparent;
  border: 2px solid #fff;
  color: #fff;
}

.btn-outline:hover {
  background: #fff;
  color: var(--primary);
}

.btn-large {
  padding: 14px 36px;
  font-size: 16px;
}

/* ========== Section Styles ========== */
.section {
  padding: 60px 0;
}

.section-gray {
  background: var(--bg-light);
}

.section-title {
  text-align: center;
  margin-bottom: 40px;
}

.section-title h2 {
  font-size: 28px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 8px;
}

.section-title p {
  color: var(--text-gray);
  font-size: 16px;
}

.section-title .underline {
  width: 60px;
  height: 3px;
  background: var(--accent);
  margin: 12px auto 0;
  border-radius: 2px;
}

/* ========== Product Categories ========== */
.categories-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 20px;
}

.category-card {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px 20px;
  text-align: center;
  transition: var(--transition);
  cursor: pointer;
}

.category-card:hover {
  box-shadow: var(--shadow-hover);
  border-color: var(--accent);
  transform: translateY(-4px);
}

.category-card .cat-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 16px;
  background: var(--accent-light);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
}

.category-card h3 {
  font-size: 15px;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 6px;
}

.category-card p {
  font-size: 13px;
  color: var(--text-gray);
}

/* ========== Product Cards ========== */
.products-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.product-card {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: var(--transition);
  display: flex;
  flex-direction: column;
}

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

.product-card .product-image {
  width: 100%;
  height: auto;
  overflow: hidden;
  background: var(--bg-light);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 8px 8px 0 8px;
}

.product-card .product-image img {
  width: 100%;
  height: auto;
  object-fit: contain;
  max-height: 200px;
  transition: var(--transition);
}

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

.product-card .product-info {
  padding: 16px;
  flex-grow: 1;
  display: flex;
  flex-direction: column;
}

.product-card .product-name {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-dark);
  margin-bottom: 8px;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.product-card .product-desc {
  font-size: 13px;
  color: var(--text-gray);
  margin-bottom: 12px;
  flex-grow: 1;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.product-card .product-price {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
}

.product-card .price-now {
  font-size: 20px;
  font-weight: 700;
  color: var(--danger);
}

.product-card .price-old {
  font-size: 14px;
  color: var(--text-light);
  text-decoration: line-through;
}

.product-card .product-actions {
  display: flex;
  gap: 8px;
}

.product-card .btn {
  flex: 1;
  font-size: 13px;
  padding: 8px 12px;
}

.badge-sale {
  position: absolute;
  top: 10px;
  left: 10px;
  background: var(--danger);
  color: #fff;
  font-size: 12px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 4px;
  z-index: 1;
}

/* Anchor-based product card (linking to detail page) */
a.product-card {
  text-decoration: none;
  color: inherit;
}

.view-detail-link {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  margin-top: auto;
  transition: var(--transition);
}

a.product-card:hover .view-detail-link {
  color: var(--primary);
}

/* ========== Promotion Section ========== */
.promo-section {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
  color: #fff;
  text-align: center;
  padding: 60px 0;
}

.promo-section h2 {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 12px;
}

.promo-section p {
  font-size: 18px;
  opacity: 0.9;
  margin-bottom: 30px;
}

.promo-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 40px;
}

.promo-card {
  background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: var(--radius);
  padding: 30px 20px;
  text-align: center;
  transition: var(--transition);
}

.promo-card:hover {
  background: rgba(255,255,255,0.15);
  transform: translateY(-4px);
}

.promo-card .promo-icon {
  font-size: 36px;
  margin-bottom: 12px;
}

.promo-card h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.promo-card p {
  font-size: 14px;
  opacity: 0.8;
  margin: 0;
}

/* ========== Features Section ========== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 30px;
}

.feature-item {
  text-align: center;
}

.feature-item .feature-icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 16px;
  background: var(--accent-light);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
}

.feature-item h3 {
  font-size: 16px;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 6px;
}

.feature-item p {
  font-size: 13px;
  color: var(--text-gray);
}

/* ========== Page Banner ========== */
.page-banner {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
  color: #fff;
  padding: 50px 0;
  text-align: center;
}

.page-banner h1 {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 8px;
}

.page-banner p {
  font-size: 16px;
  opacity: 0.85;
}

.breadcrumb {
  display: flex;
  justify-content: center;
  gap: 8px;
  font-size: 13px;
  margin-top: 12px;
}

.breadcrumb a {
  color: #aaccff;
}

.breadcrumb a:hover {
  color: #fff;
}

.breadcrumb span {
  opacity: 0.6;
}

/* ========== Product Category Section ========== */
.category-section {
  margin-bottom: 50px;
}

.category-section .cat-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 24px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--border);
}

.category-section .cat-header .cat-num {
  width: 36px;
  height: 36px;
  background: var(--primary);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  font-weight: 700;
}

.category-section .cat-header h2 {
  font-size: 22px;
  font-weight: 700;
  color: var(--primary);
}

.category-section .cat-header p {
  font-size: 14px;
  color: var(--text-gray);
  margin-left: auto;
}

/* ========== FAQ Section ========== */
.faq-container {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 12px;
  overflow: hidden;
  transition: var(--transition);
}

.faq-item.active {
  border-color: var(--accent);
  box-shadow: var(--shadow);
}

.faq-question {
  padding: 18px 24px;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 600;
  font-size: 15px;
  color: var(--primary);
  background: var(--bg-white);
  transition: var(--transition);
}

.faq-question:hover {
  background: var(--bg-light);
}

.faq-question .faq-icon {
  font-size: 20px;
  transition: var(--transition);
  color: var(--accent);
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
  background: var(--bg-light);
}

.faq-item.active .faq-answer {
  max-height: 600px;
}

.faq-answer-inner {
  padding: 18px 24px;
  font-size: 14px;
  color: var(--text-gray);
  line-height: 1.8;
}

/* ========== Technology Articles ========== */
.tech-article {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px;
  margin-bottom: 24px;
  transition: var(--transition);
}

.tech-article:hover {
  box-shadow: var(--shadow);
}

.tech-article .article-number {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  font-size: 13px;
  font-weight: 600;
  padding: 3px 12px;
  border-radius: 20px;
  margin-bottom: 12px;
}

.tech-article h3 {
  font-size: 20px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 12px;
}

.tech-article .article-meta {
  font-size: 13px;
  color: var(--text-light);
  margin-bottom: 16px;
}

.tech-article p {
  font-size: 14px;
  color: var(--text-gray);
  margin-bottom: 12px;
}

.tech-article h4 {
  font-size: 15px;
  font-weight: 600;
  color: var(--primary);
  margin: 16px 0 8px;
}

.tech-article ul {
  padding-left: 20px;
  margin-bottom: 12px;
}

.tech-article ul li {
  font-size: 14px;
  color: var(--text-gray);
  margin-bottom: 4px;
}

.tech-article .article-footer {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  font-size: 13px;
  color: var(--text-light);
}

/* ========== Contact Page ========== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}

.contact-info-item {
  display: flex;
  gap: 16px;
  margin-bottom: 24px;
}

.contact-info-item .ci-icon {
  width: 48px;
  height: 48px;
  background: var(--accent-light);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  flex-shrink: 0;
}

.contact-info-item h4 {
  font-size: 15px;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 4px;
}

.contact-info-item p {
  font-size: 14px;
  color: var(--text-gray);
}

.contact-form {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 6px;
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 14px;
  font-family: inherit;
  transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-light);
}

/* ========== About Page ========== */
.about-hero {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
}

.about-hero h2 {
  font-size: 28px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 16px;
}

.about-hero p {
  font-size: 15px;
  color: var(--text-gray);
  margin-bottom: 16px;
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 40px;
}

.stat-item {
  text-align: center;
  padding: 30px 20px;
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.stat-item .stat-num {
  font-size: 36px;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 4px;
}

.stat-item .stat-label {
  font-size: 14px;
  color: var(--text-gray);
}

/* ========== Footer ========== */
.footer {
  background: var(--primary);
  color: #b0c4d8;
  padding: 50px 0 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-col h4 {
  color: #fff;
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 16px;
}

.footer-col p {
  font-size: 14px;
  line-height: 1.8;
  margin-bottom: 12px;
}

.footer-col ul {
  list-style: none;
}

.footer-col ul li {
  margin-bottom: 8px;
}

.footer-col ul li a {
  color: #b0c4d8;
  font-size: 14px;
  transition: var(--transition);
}

.footer-col ul li a:hover {
  color: #fff;
  padding-left: 4px;
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 20px 0;
  text-align: center;
  font-size: 13px;
}

.footer-bottom a {
  color: #aaccff;
}


/* ========== Tech Article Prev/Next Navigation ========== */
.tech-prev-next {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 12px 0 0 0;
  gap: 40px;
  flex-wrap: wrap;
}

.tech-prev-next .prev-link,
.tech-prev-next .next-link {
  color: rgba(255,255,255,0.9);
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  transition: var(--transition);
}

.tech-prev-next .prev-link:hover,
.tech-prev-next .next-link:hover {
  color: #fff;
  text-decoration: underline;
}

@media (max-width: 768px) {
  .tech-prev-next {
    flex-direction: column;
    align-items: center;
    gap: 6px;
  }
  .tech-prev-next .prev-link,
  .tech-prev-next .next-link {
    text-align: center;
    max-width: 100%;
  }
}


/* ========== Product Prev/Next Navigation ========== */
.product-prev-next {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 12px 0 0 0;
  gap: 40px;
  flex-wrap: wrap;
}

.product-prev-next .prev-link,
.product-prev-next .next-link {
  color: rgba(255,255,255,0.9);
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  transition: var(--transition);

}

.product-prev-next .prev-link:hover,
.product-prev-next .next-link:hover {
  color: #fff;
  text-decoration: underline;
}

.product-prev-next .next-link {
  text-align: left;
}

@media (max-width: 768px) {
  .product-prev-next {
    flex-direction: column;
    align-items: center;
    gap: 6px;
  }
  .product-prev-next .prev-link,
  .product-prev-next .next-link {
    max-width: 100%;
  }
  .product-prev-next .next-link {
    text-align: center;
  }
  .product-prev-next .prev-link {
    text-align: center;
  }
}

/* ========== Responsive ========== */
@media (max-width: 1024px) {
  .categories-grid { grid-template-columns: repeat(3, 1fr); }
  .products-grid { grid-template-columns: repeat(3, 1fr); }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .promo-cards { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .about-stats { grid-template-columns: repeat(2, 1fr); }

}

@media (max-width: 768px) {
  .nav-menu {
    display: none;
    position: absolute;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: var(--bg-white);
    flex-direction: column;
    padding: 16px;
    box-shadow: var(--shadow);
  }

  .nav-menu.active {
    display: flex;
  }

  .nav-toggle {
    display: block;
  }

  .nav-lang-item {
    display: block;
  }

  .nav-lang-item:first-of-type {
    margin-top: 12px;
    padding-top: 12px;
    border-top: 1px solid var(--border);
  }

  .nav-lang-item a {
    display: inline-block;
    padding: 8px 16px;
    margin: 4px;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-gray);
    border-radius: 6px;
    text-align: center;
    border: 1px solid var(--border);
    background: var(--bg-light);
  }

  .nav-lang-item a:hover {
    background: var(--accent-light);
    color: var(--accent);
  }

  .nav-lang-item a.active {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
  }

  .header-top {
    padding: 4px 0;
  }

  .header-top .container {
    justify-content: center;
  }

  .header-top .container > span {
    display: none;
  }

  .hero { height: 320px; }
  .carousel-slide .slide-content h2 { font-size: 24px; }
  .carousel-slide .slide-content p { font-size: 15px; }

  .categories-grid { grid-template-columns: repeat(2, 1fr); }
  .products-grid { grid-template-columns: repeat(2, 1fr); }
  .features-grid { grid-template-columns: 1fr; }
  .promo-cards { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .about-hero { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .about-stats { grid-template-columns: repeat(2, 1fr); }

  .section { padding: 40px 0; }
  .section-title h2 { font-size: 22px; }
}

@media (max-width: 480px) {
  .categories-grid { grid-template-columns: 1fr; }
  .products-grid { grid-template-columns: 1fr; }
  .about-stats { grid-template-columns: 1fr; }
  .carousel-slide .slide-content h2 { font-size: 20px; }
}

/* ========== Subcategory Navigation ========== */
.subcat-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 30px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border);
}

.subcat-nav .subcat-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--primary);
  margin-right: 8px;
  align-self: center;
}

.subcat-pill {
  display: inline-block;
  padding: 6px 16px;
  background: var(--bg-light);
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-gray);
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
}

.subcat-pill:hover,
.subcat-pill.active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

/* Subcategory group heading */
.subcat-group {
  margin-bottom: 40px;
}

.subcat-group-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 16px;
  padding-left: 12px;
  border-left: 4px solid var(--accent);
}

/* ========== Product Detail Page ========== */
.product-detail {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.product-detail-image {
  background: var(--bg-light);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 350px;
}

.product-detail-image img {
  max-width: 100%;
  max-height: 400px;
  object-fit: contain;
}

.product-detail-info h1 {
  font-size: 24px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 16px;
  line-height: 1.4;
}

.product-detail-info .product-detail-desc {
  font-size: 15px;
  color: var(--text-gray);
  line-height: 1.8;
  margin-bottom: 24px;
}

.product-detail-info .buy-now-btn {
  display: inline-block;
  padding: 14px 40px;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  font-size: 16px;
  font-weight: 700;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
}

.product-detail-info .buy-now-btn:hover {
  background: var(--primary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-hover);
}

/* Attention box */
.attention-box {
  background: #fff3cd;
  border: 1px solid #ffc107;
  border-radius: 8px;
  padding: 16px 20px;
  margin: 20px 0;
  color: #856404;
  font-size: 15px;
  line-height: 1.6;
}

/* Technology Nav Grid (homepage) */
.tech-nav-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-bottom: 30px;
}

.tech-nav-item {
  flex: 0 0 calc(50% - 6px);
  min-width: 0;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: 8px;
  text-decoration: none;
  transition: var(--transition);
}

.tech-nav-item:hover {
  border-color: var(--primary);
  box-shadow: 0 2px 12px rgba(0,128,255,0.1);
  transform: translateY(-2px);
}

.tech-nav-num {
  font-size: 13px;
  font-weight: 700;
  color: var(--primary);
  min-width: 34px;
  flex-shrink: 0;
}

.tech-nav-cat {
  font-size: 11px;
  font-weight: 600;
  color: #888;
  background: var(--bg-light);
  padding: 3px 8px;
  border-radius: 4px;
  white-space: nowrap;
  flex-shrink: 0;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.tech-nav-title {
  font-size: 14px;
  color: var(--text-dark);
  line-height: 1.4;
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.tech-nav-item:hover .tech-nav-title {
  color: var(--primary);
}

.tech-nav-footer {
  text-align: center;
}

@media (max-width: 1024px) {
  .tech-nav-item { flex: 0 0 100%; }
}

/* Spec table */
.spec-table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 30px;
}

.spec-table th,
.spec-table td {
  padding: 12px 16px;
  border: 1px solid var(--border);
  font-size: 14px;
}

.spec-table th {
  background: var(--bg-light);
  font-weight: 600;
  color: var(--primary);
  width: 30%;
}

.spec-table td {
  color: var(--text-gray);
}

/* Detail page section */
.detail-section {
  margin-bottom: 40px;
}

.detail-section h2 {
  font-size: 20px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--accent);
}

.detail-section p,
.detail-section li {
  font-size: 15px;
  color: var(--text-gray);
  line-height: 1.8;
  margin-bottom: 10px;
}

.detail-section ul {
  padding-left: 20px;
  margin-bottom: 16px;
}

/* Related products */
.related-products {
  margin-top: 50px;
}

.related-products h2 {
  font-size: 20px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 20px;
}

/* ========== Article Summary Card ========== */
.article-card {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  margin-bottom: 20px;
  transition: var(--transition);
  display: block;
  text-decoration: none;
}

.article-card:hover {
  box-shadow: var(--shadow-hover);
  border-color: var(--accent);
  transform: translateY(-2px);
}

.article-card .article-cat {
  display: inline-block;
  background: var(--accent-light);
  color: var(--accent);
  font-size: 12px;
  font-weight: 600;
  padding: 3px 12px;
  border-radius: 20px;
  margin-bottom: 10px;
}

.article-card h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 10px;
}

.article-card .article-summary {
  font-size: 14px;
  color: var(--text-gray);
  line-height: 1.7;
  margin-bottom: 12px;
}

.article-card .read-more {
  font-size: 14px;
  font-weight: 600;
  color: var(--accent);
}

.article-card:hover .read-more {
  color: var(--primary);
}

/* ========== Article Detail Page ========== */
.article-detail {
  margin: 0 auto;
}

.article-detail h1 {
  font-size: 28px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-detail .article-detail-meta {
  font-size: 14px;
  color: var(--text-light);
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

.article-detail h2 {
  font-size: 20px;
  font-weight: 700;
  color: var(--primary);
  margin: 24px 0 12px;
}

.article-detail p {
  font-size: 15px;
  color: var(--text-gray);
  line-height: 1.8;
  margin-bottom: 14px;
}

.article-detail ul {
  padding-left: 20px;
  margin-bottom: 16px;
}

.article-detail ul li {
  font-size: 15px;
  color: var(--text-gray);
  line-height: 1.8;
  margin-bottom: 6px;
}

.article-detail .article-nav {
  display: flex;
  justify-content: space-between;
  margin-top: 40px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.article-detail .article-nav a {
  font-size: 14px;
  font-weight: 600;
}

/* Article card new class names */
.article-card-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
}

.article-card .article-number {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  font-size: 11px;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 4px;
}

.article-cat-tag {
  display: inline-block;
  background: var(--accent-light);
  color: var(--accent);
  font-size: 12px;
  font-weight: 600;
  padding: 3px 12px;
  border-radius: 20px;
}

.article-card-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 10px;
  line-height: 1.4;
}

.article-card-summary {
  font-size: 14px;
  color: var(--text-gray);
  line-height: 1.7;
  margin-bottom: 12px;
}

.article-card-readmore {
  font-size: 14px;
  font-weight: 600;
  color: var(--accent);
  transition: var(--transition);
}

.article-card:hover .article-card-readmore {
  color: var(--primary);
}

.article-card-meta {
  font-size: 13px;
  color: var(--text-light);
  margin-top: 8px;
}

/* Article detail page new styles */
.article-detail-title {
  font-size: 28px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-detail-meta {
  font-size: 14px;
  color: var(--text-light);
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.article-detail-meta .article-number {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 4px;
}

.article-detail-content h4 {
  font-size: 17px;
  font-weight: 700;
  color: var(--primary);
  margin: 20px 0 10px;
}

.article-detail-content ol {
  padding-left: 20px;
  margin-bottom: 16px;
}

.article-detail-content ol li {
  font-size: 15px;
  color: var(--text-gray);
  line-height: 1.8;
  margin-bottom: 6px;
}

.article-detail .article-nav {
  flex-wrap: wrap;
  gap: 10px;
}

.article-detail .article-footer {
  margin-top: 16px;
  padding: 12px 16px;
  background: var(--bg-light);
  border-radius: var(--radius);
  font-size: 14px;
}

.article-detail .article-footer a {
  color: var(--accent);
  font-weight: 600;
}

/* Responsive for detail pages */
@media (max-width: 768px) {
  .product-detail { grid-template-columns: 1fr; }
  .subcat-nav { flex-direction: column; align-items: flex-start; }
  .article-detail-meta { flex-direction: column; gap: 8px; }
  .article-detail .article-nav { flex-direction: column; }
}

/* (splitter-product override removed - base product-image styles now use full-width display for all cards) */