:root {
  --primary: #1a6dff;
  --primary-dark: #1450c2;
  --secondary: #0f172a;
  --bg: #f5f7fa;
  --card: #ffffff;
  --text: #1f2937;
  --text-muted: #6b7280;
  --border: #e5e7eb;
  --radius: 12px;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
  --shadow-hover: 0 8px 30px rgba(0, 0, 0, 0.1);
  --success: #16a34a;
  --warning: #d97706;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

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

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

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.page-section {
  padding: 40px 0;
}

.page-title {
  font-size: 28px;
  font-weight: 700;
  margin: 0 0 24px;
}

.section-title {
  font-size: 22px;
  font-weight: 700;
  margin: 0 0 16px;
}

/* Header */
#site-header {
  background: var(--card);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 1px;
  color: var(--primary);
  padding: 6px 14px 6px 10px;
  border-radius: 10px;
  background: rgba(37, 99, 235, 0.08);
  border: 1px solid rgba(37, 99, 235, 0.18);
  transition: background 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease;
}

.logo:hover {
  background: rgba(37, 99, 235, 0.14);
  box-shadow: 0 6px 18px rgba(37, 99, 235, 0.14);
  transform: translateY(-1px);
}

.logo-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: linear-gradient(135deg, #eff6ff, #dbeafe);
  box-shadow: inset 0 0 0 1px rgba(37, 99, 235, 0.12), 0 2px 8px rgba(37, 99, 235, 0.12);
  flex-shrink: 0;
}

.logo-mark svg {
  display: block;
}

.logo-text {
  background: linear-gradient(135deg, var(--primary), #1d4ed8);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  white-space: nowrap;
}

.main-nav {
  display: flex;
  gap: 28px;
}

.main-nav a {
  font-size: 15px;
  color: var(--text);
  font-weight: 500;
  transition: color 0.2s;
}

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

.header-actions {
  display: flex;
  align-items: center;
  gap: 14px;
}

.cart-link {
  position: relative;
  color: var(--text);
}

.cart-badge {
  position: absolute;
  top: -8px;
  right: -8px;
  min-width: 18px;
  height: 18px;
  padding: 0 5px;
  border-radius: 9px;
  background: var(--primary);
  color: #fff;
  font-size: 11px;
  align-items: center;
  justify-content: center;
}

.user-menu {
  position: relative;
}

.user-toggle {
  display: flex;
  align-items: center;
  gap: 6px;
  background: none;
  border: none;
  font-size: 14px;
  color: var(--text);
  cursor: pointer;
}

.user-dropdown {
  position: absolute;
  top: 110%;
  right: 0;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-hover);
  min-width: 140px;
  display: none;
  flex-direction: column;
  padding: 8px 0;
}

.user-dropdown.open {
  display: flex;
}

.user-dropdown a,
.user-dropdown button {
  padding: 10px 16px;
  font-size: 14px;
  background: none;
  border: none;
  text-align: left;
  cursor: pointer;
  color: var(--text);
}

.user-dropdown a:hover,
.user-dropdown button:hover {
  background: #f3f4f6;
  color: var(--primary);
}

.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}

.menu-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text);
  transition: transform 0.2s;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 20px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.2s;
}

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

.btn-primary:hover {
  background: var(--primary-dark);
}

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

.btn-outline:hover {
  background: #eff6ff;
}

.btn-lg {
  padding: 14px 32px;
  font-size: 16px;
}

.btn-sm {
  padding: 6px 14px;
  font-size: 13px;
}

.btn-danger {
  background: #fee2e2;
  color: #b91c1c;
}

.btn-danger:hover {
  background: #fecaca;
}

.btn-block {
  width: 100%;
}

/* Cards */
.card {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: transform 0.2s, box-shadow 0.2s;
}

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

.card-img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  background: #f3f4f6;
}

.card-body {
  padding: 16px;
}

.card-title {
  font-size: 16px;
  font-weight: 600;
  margin: 0 0 8px;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.card-meta {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 10px;
}

.card-price {
  font-size: 18px;
  font-weight: 700;
  color: var(--primary);
}

.card-price del {
  font-size: 13px;
  color: var(--text-muted);
  margin-left: 6px;
  font-weight: 400;
}

/* Forms */
.form-group {
  margin-bottom: 18px;
}

.form-label {
  display: block;
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 6px;
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 14px;
  background: #fff;
  transition: border-color 0.2s;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--primary);
}

.form-textarea {
  min-height: 120px;
  resize: vertical;
}

.checkbox-group {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  font-size: 13px;
  color: var(--text-muted);
}

.checkbox-group input {
  margin-top: 3px;
}

/* Hero */
.hero {
  background: linear-gradient(135deg, #0f172a 0%, #1e3a8a 100%);
  color: #fff;
  padding: 80px 0;
}

.hero-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
  align-items: center;
}

.hero-inner > div {
  max-width: 640px;
}

.hero h1 {
  font-size: 40px;
  margin: 0 0 16px;
  line-height: 1.2;
}

.hero p {
  font-size: 17px;
  opacity: 0.9;
  margin: 0 0 28px;
}

.hero-actions {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.hero-card {
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius);
  padding: 24px;
}

.hero-card h3 {
  margin: 0 0 10px;
  font-size: 20px;
}

.hero-card p {
  margin: 0 0 16px;
  font-size: 14px;
}

/* Module cards */
.module-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.module-card {
  background: var(--card);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  transition: transform 0.2s, box-shadow 0.2s;
}

.module-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}

.module-card h3 {
  margin: 0 0 12px;
  font-size: 22px;
}

.module-card p {
  color: var(--text-muted);
  margin: 0 0 20px;
  font-size: 14px;
}

/* Filter bar */
.filter-bar {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  align-items: center;
  margin-bottom: 24px;
}

.filter-btn {
  padding: 8px 16px;
  border-radius: 20px;
  border: 1px solid var(--border);
  background: #fff;
  font-size: 13px;
  cursor: pointer;
  transition: all 0.2s;
}

.filter-btn.active,
.filter-btn:hover {
  background: var(--primary);
  color: #fff;
  border-color: var(--primary);
}

.search-input {
  min-width: 220px;
}

/* Grids */
.product-grid,
.info-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 20px;
}

.info-grid {
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
}

/* Tags */
.tag {
  display: inline-block;
  padding: 3px 8px;
  border-radius: 4px;
  background: #eff6ff;
  color: var(--primary);
  font-size: 12px;
  margin-right: 6px;
}

/* Product detail */
.product-detail {
  display: grid;
  grid-template-columns: 1fr 1fr 300px;
  gap: 32px;
  align-items: start;
  background: var(--card);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
}

.gallery-main {
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  border-radius: var(--radius);
  background: #f3f4f6;
}

.gallery-thumbs {
  display: flex;
  gap: 10px;
  margin-top: 12px;
  overflow-x: auto;
}

.gallery-thumbs img {
  width: 72px;
  height: 72px;
  object-fit: cover;
  border-radius: 8px;
  border: 2px solid transparent;
  cursor: pointer;
}

.gallery-thumbs img.active {
  border-color: var(--primary);
}

.product-info h1 {
  font-size: 24px;
  margin: 0 0 12px;
}

.product-info .price {
  font-size: 32px;
  font-weight: 800;
  color: var(--primary);
  margin-bottom: 12px;
}

.product-info .price del {
  font-size: 16px;
  color: var(--text-muted);
  margin-left: 10px;
  font-weight: 400;
}

.merchant-line {
  color: var(--text-muted);
  font-size: 14px;
  margin-bottom: 16px;
}

.merchant-sidebar {
  min-width: 0;
}

.merchant-card {
  background: #f8fafc;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
}

.merchant-card h3 {
  font-size: 17px;
  margin: 0 0 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
}

.merchant-field {
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin-bottom: 14px;
}

.merchant-label {
  font-size: 13px;
  color: var(--text-muted);
}

.merchant-value {
  font-size: 14px;
  color: var(--text);
  font-weight: 500;
  word-break: break-all;
}

.merchant-tip {
  font-size: 12px;
  color: var(--primary);
}

.spec-table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0;
  font-size: 14px;
}

.spec-table td {
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
}

.spec-table td:first-child {
  color: var(--text-muted);
  width: 120px;
}

.qty-control {
  display: inline-flex;
  align-items: center;
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  margin-right: 12px;
}

.qty-control button {
  width: 36px;
  height: 36px;
  border: none;
  background: #f3f4f6;
  cursor: pointer;
  font-size: 16px;
}

.qty-control input {
  width: 48px;
  height: 36px;
  border: none;
  text-align: center;
  font-size: 14px;
}

/* Cart */
.cart-table {
  width: 100%;
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.cart-table th,
.cart-table td {
  padding: 16px;
  text-align: left;
  border-bottom: 1px solid var(--border);
  font-size: 14px;
}

.cart-table th {
  background: #f9fafb;
  font-weight: 600;
}

.cart-item-info {
  display: flex;
  gap: 12px;
  align-items: center;
}

.cart-item-info img {
  width: 60px;
  height: 60px;
  object-fit: cover;
  border-radius: 8px;
}

.cart-summary {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
  margin-top: 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

.cart-summary .total {
  font-size: 20px;
  font-weight: 700;
}

/* Info detail */
.info-detail-card {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 28px;
}

.info-detail-card h1 {
  font-size: 24px;
  margin: 0 0 12px;
}

.info-detail-card .meta {
  color: var(--text-muted);
  font-size: 14px;
  margin-bottom: 20px;
}

.info-detail-card img {
  width: 100%;
  border-radius: var(--radius);
  margin-bottom: 20px;
}

.info-detail-card .content {
  font-size: 15px;
  line-height: 1.8;
}

.contact-card {
  background: #f9fafb;
  border-radius: var(--radius);
  padding: 20px;
  margin-top: 24px;
}

.contact-card h4 {
  margin: 0 0 12px;
}

/* Info detail layout with publisher sidebar */
.info-detail-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 28px;
  align-items: start;
}

.info-detail-main {
  min-width: 0;
}

.publisher-sidebar {
  min-width: 0;
}

.publisher-card {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
}

.publisher-card h3 {
  font-size: 17px;
  margin: 0 0 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
}

.publisher-field {
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin-bottom: 14px;
}

.publisher-label {
  font-size: 13px;
  color: var(--text-muted);
}

.publisher-value {
  font-size: 14px;
  color: var(--text);
  font-weight: 500;
  word-break: break-all;
}

.publisher-tip {
  font-size: 12px;
  color: var(--primary);
}

@media (max-width: 900px) {
  .info-detail-layout {
    grid-template-columns: 1fr;
  }
}

/* Login / Register */
.auth-container {
  max-width: 420px;
  margin: 60px auto;
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 36px;
}

.auth-container h2 {
  text-align: center;
  margin: 0 0 6px;
  font-size: 24px;
}

.auth-container .subtitle {
  text-align: center;
  color: var(--text-muted);
  font-size: 14px;
  margin-bottom: 24px;
}

.auth-footer {
  text-align: center;
  margin-top: 20px;
  font-size: 14px;
  color: var(--text-muted);
}

.auth-footer a {
  color: var(--primary);
}

/* Footer */
#site-footer {
  background: var(--secondary);
  color: #cbd5e1;
  padding: 48px 0 24px;
  margin-top: 60px;
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.footer-main {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 32px;
}

.footer-brand strong {
  color: #fff;
  font-size: 18px;
  display: block;
  margin-bottom: 10px;
}

.footer-brand p,
.footer-contact p {
  margin: 6px 0;
  font-size: 14px;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: 14px;
}

.footer-links a:hover {
  color: #fff;
}

.footer-contact .footer-address {
  margin: 6px 0 0;
  line-height: 1.6;
}

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

.footer-bottom a {
  color: #cbd5e1;
}

.footer-bottom a:hover {
  color: #fff;
}

/* About page */
.about-company {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 32px;
}

.about-company h2 {
  margin-top: 0;
}

.info-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 16px;
  margin: 20px 0;
}

.info-item {
  background: #f9fafb;
  border-radius: 8px;
  padding: 14px 16px;
  font-size: 14px;
}

.info-item strong {
  display: block;
  color: var(--text-muted);
  font-size: 12px;
  margin-bottom: 4px;
}

/* Empty state */
.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--text-muted);
}

.empty-state h3 {
  color: var(--text);
  margin-bottom: 10px;
}

/* Toast */
.toast {
  position: fixed;
  top: 80px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--secondary);
  color: #fff;
  padding: 12px 24px;
  border-radius: 8px;
  font-size: 14px;
  z-index: 200;
  box-shadow: var(--shadow-hover);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s;
}

.toast.show {
  opacity: 1;
}

/* Responsive */
@media (max-width: 1100px) {
  .product-detail {
    grid-template-columns: 1fr 1fr;
  }

  .merchant-sidebar {
    grid-column: 1 / -1;
  }
}

@media (max-width: 900px) {
  .hero-inner,
  .product-detail {
    grid-template-columns: 1fr;
  }

  .merchant-sidebar {
    grid-column: auto;
  }

  .footer-main {
    grid-template-columns: 1fr;
    gap: 24px;
  }
}

@media (max-width: 768px) {
  .menu-toggle {
    display: flex;
  }

  .main-nav {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--card);
    flex-direction: column;
    padding: 16px 20px;
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow);
  }

  .main-nav.open {
    display: flex;
  }

  .header-actions .btn {
    display: none;
  }

  .hero h1 {
    font-size: 28px;
  }

  .product-grid,
  .info-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 480px) {
  .product-grid,
  .info-grid {
    grid-template-columns: 1fr;
  }

  .auth-container {
    padding: 24px;
    margin: 30px auto;
  }
}