/* ============================================
   Shanghai QN Technology Co., Ltd. - Design System
   Company: 上海麒诺机电科技
   Domain: www.shqn.top
   ============================================ */

/* --- CSS Custom Properties --- */
:root {
  /* Primary palette */
  --color-primary: #0A1628;        /* Deep navy - headers, text */
  --color-primary-light: #1A2B45;
  --color-accent: #D71920;         /* Brand red from QN logo */
  --color-accent-hover: #B8151A;
  --color-accent-light: #FDE8E9;

  /* Secondary palette */
  --color-success: #059669;
  --color-warning: #D97706;
  --color-info: #2563EB;

  /* Neutrals */
  --color-bg: #F5F6F8;
  --color-bg-alt: #EEF0F3;
  --color-surface: #FFFFFF;
  --color-border: #E2E5EA;
  --color-border-light: #F0F2F5;

  /* Text */
  --text-primary: #1A1A2E;
  --text-secondary: #4A5568;
  --text-muted: #718096;
  --text-inverse: #FFFFFF;
  --text-on-accent: #FFFFFF;

  /* Typography */
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;

  /* Font sizes - modular scale */
  --text-xs: 0.75rem;     /* 12px */
  --text-sm: 0.875rem;    /* 14px */
  --text-base: 1rem;      /* 16px */
  --text-lg: 1.125rem;    /* 18px */
  --text-xl: 1.25rem;     /* 20px */
  --text-2xl: 1.5rem;     /* 24px */
  --text-3xl: 1.875rem;   /* 30px */
  --text-4xl: 2.25rem;    /* 36px */
  --text-5xl: 3rem;       /* 48px */

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;

  /* Layout */
  --max-width: 1200px;
  --header-height: 72px;

  /* Borders & Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.12);
  --shadow-xl: 0 16px 50px rgba(0,0,0,0.16);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;
}

/* --- Reset & Base --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-family);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--color-accent); text-decoration: none; transition: color var(--transition-fast); }
a:hover { color: var(--color-accent-hover); }
a:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }

ul, ol { list-style: none; }

/* --- Utility --- */
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 var(--space-lg); }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0,0,0,0); border: 0; }

.text-center { text-align: center; }
.text-accent { color: var(--color-accent); }
.text-muted { color: var(--text-muted); }
.text-sm { font-size: var(--text-sm); }
.text-lg { font-size: var(--text-lg); }

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 0.625rem 1.5rem;
  font-size: var(--text-sm);
  font-weight: 600;
  line-height: 1.4;
  border: 2px solid transparent;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-base);
  white-space: nowrap;
  text-decoration: none;
}
.btn:hover { transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn:active { transform: translateY(0); }

.btn-primary {
  background: var(--color-accent);
  color: var(--text-on-accent);
  border-color: var(--color-accent);
}
.btn-primary:hover { background: var(--color-accent-hover); border-color: var(--color-accent-hover); color: var(--text-on-accent); }

.btn-secondary {
  background: var(--color-surface);
  color: var(--text-primary);
  border-color: var(--color-border);
}
.btn-secondary:hover { border-color: var(--color-accent); color: var(--color-accent); }

.btn-outline {
  background: transparent;
  color: var(--text-inverse);
  border-color: var(--text-inverse);
}
.btn-outline:hover { background: var(--text-inverse); color: var(--color-primary); }

.btn-lg { padding: 0.875rem 2rem; font-size: var(--text-base); }
.btn-sm { padding: 0.375rem 1rem; font-size: var(--text-xs); }

/* --- Header --- */
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border-light);
  height: var(--header-height);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  gap: var(--space-xl);
}

.header-logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  flex-shrink: 0;
}
.header-logo img { height: 40px; width: auto; }
.header-logo span {
  font-size: var(--text-xl);
  font-weight: 800;
  color: var(--color-primary);
  letter-spacing: -0.02em;
}
.header-logo small {
  display: block;
  font-size: var(--text-xs);
  font-weight: 400;
  color: var(--text-muted);
  letter-spacing: 0;
}

.header-nav {
  display: flex;
  align-items: center;
  gap: var(--space-xl);
}
.header-nav a {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--text-secondary);
  position: relative;
  padding: var(--space-xs) 0;
  transition: color var(--transition-fast);
}
.header-nav a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-accent);
  transition: width var(--transition-base);
}
.header-nav a:hover,
.header-nav a.active { color: var(--color-primary); }
.header-nav a:hover::after,
.header-nav a.active::after { width: 100%; }

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  flex-shrink: 0;
}

.lang-switch {
  background: none;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 4px 10px;
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
}
.lang-switch:hover { border-color: var(--color-accent); color: var(--color-accent); }

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-sm);
}

/* --- Hero Section --- */
.hero {
  background: linear-gradient(135deg, #0A1628 0%, #1A2B45 50%, #0d2137 100%);
  color: var(--text-inverse);
  padding: var(--space-4xl) 0;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 80%;
  height: 200%;
  background: radial-gradient(ellipse, rgba(215,29,32,0.08) 0%, transparent 70%);
  pointer-events: none;
}
.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-3xl);
  align-items: center;
  position: relative;
  z-index: 1;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  background: rgba(215,29,32,0.15);
  border: 1px solid rgba(215,29,32,0.3);
  padding: 6px 14px;
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  font-weight: 600;
  color: #FF6B6B;
  margin-bottom: var(--space-lg);
  letter-spacing: 0.03em;
}
.hero h1 {
  font-size: var(--text-5xl);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: var(--space-lg);
  letter-spacing: -0.02em;
}
.hero h1 .highlight { color: #FF6B6B; }
.hero p {
  font-size: var(--text-lg);
  opacity: 0.85;
  line-height: 1.7;
  margin-bottom: var(--space-2xl);
  max-width: 520px;
}
.hero-ctas { display: flex; gap: var(--space-md); flex-wrap: wrap; }
.hero-image {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  aspect-ratio: 4/3;
  background: linear-gradient(135deg, #1a2b45, #0d2137);
  display: flex;
  align-items: center;
  justify-content: center;
}
.hero-image-placeholder {
  text-align: center;
  color: rgba(255,255,255,0.3);
  font-size: var(--text-sm);
}
.hero-image-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

/* --- Section Common --- */
.section {
  padding: var(--space-4xl) 0;
}
.section-header {
  text-align: center;
  max-width: 640px;
  margin: 0 auto var(--space-3xl);
}
.section-header .label {
  display: inline-block;
  font-size: var(--text-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-accent);
  margin-bottom: var(--space-sm);
}
.section-header h2 {
  font-size: var(--text-4xl);
  font-weight: 800;
  color: var(--color-primary);
  margin-bottom: var(--space-md);
  letter-spacing: -0.02em;
}
.section-header p {
  font-size: var(--text-lg);
  color: var(--text-secondary);
  line-height: 1.7;
}

/* --- Brand Cards --- */
.brand-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: var(--space-lg);
}
.brand-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  transition: all var(--transition-base);
  display: flex;
  gap: var(--space-lg);
  align-items: flex-start;
}
.brand-card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}
.brand-card-logo {
  width: 64px;
  height: 64px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-2xl);
  font-weight: 800;
  color: #FFF;
  flex-shrink: 0;
}
.brand-card-logo-img {
  padding: 8px;
  border: 1px solid var(--color-border);
  box-sizing: border-box;
}
.brand-card-logo-img img { width: 100%; height: 100%; object-fit: contain; }

/* ===== A-Z Brand Index ===== */
html { scroll-behavior: smooth; }
.az-nav {
  position: sticky;
  top: 68px;
  z-index: 50;
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 10px 12px;
  margin-bottom: var(--space-xl);
  box-shadow: var(--shadow-sm);
}
.az-letter {
  min-width: 34px;
  height: 34px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 6px;
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--color-accent);
  text-decoration: none;
  transition: all var(--transition-fast);
  padding: 0 4px;
}
.az-letter:hover { background: var(--color-accent-light); }
.az-letter.active { background: var(--color-accent); color: #fff; }
.az-letter.disabled {
  color: var(--color-border);
  cursor: default;
  pointer-events: none;
}
.az-section {
  margin-bottom: var(--space-2xl);
  scroll-margin-top: 150px;
}
.az-section-title {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-sm);
  border-bottom: 2px solid var(--color-border);
}
.az-section-title span {
  font-size: var(--text-3xl);
  font-weight: 800;
  color: var(--color-primary);
  line-height: 1;
}
.az-section-title::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--color-border);
}

/* ===== Category quick-nav (products page) ===== */
.cat-nav {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  margin-bottom: var(--space-2xl);
}
.cat-pill {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 18px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  text-decoration: none;
  color: var(--color-primary);
  font-size: var(--text-sm);
  font-weight: 600;
  transition: all var(--transition-fast);
}
.cat-pill:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  box-shadow: var(--shadow-sm);
}
.cat-pill-icon {
  width: 26px;
  height: 26px;
  display: inline-flex;
  color: var(--color-accent);
}
.cat-pill-icon svg { width: 100%; height: 100%; }

/* ===== Product catalog list ===== */
.product-catalog-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: var(--space-lg);
}
.product-catalog-item {
  display: block;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg) var(--space-xl);
  text-decoration: none;
  color: inherit;
  transition: all var(--transition-base);
}
.product-catalog-item:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}
.pci-thumb {
  width: 100%;
  height: 168px;
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--color-bg);
  border: 1px solid var(--color-border-light);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--space-md);
}
.pci-thumb img { width: 100%; height: 100%; object-fit: contain; }
.pci-brand {
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: .04em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 6px;
}
.pci-name {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 6px;
}
.pci-desc {
  font-size: var(--text-sm);
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 10px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.pci-code {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--text-secondary);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  padding: 2px 8px;
  display: inline-block;
}
.brand-card-body { flex: 1; min-width: 0; }
.brand-card-body h3 {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 4px;
}
.brand-card-body h3 a { color: inherit; }
.brand-card-body h3 a:hover { color: var(--color-accent); }
.brand-card-meta {
  font-size: var(--text-sm);
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: var(--space-md);
  flex-wrap: wrap;
}
.brand-card-meta .dot {
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--color-border);
  display: inline-block;
}
.brand-card-count {
  margin-top: var(--space-md);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-accent);
}

/* --- Advantages / Features --- */
.advantages-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-lg);
}
.advantage-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  text-align: center;
  transition: all var(--transition-base);
}
.advantage-card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-md);
}
.advantage-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-lg);
  background: var(--color-accent-light);
  color: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--space-lg);
  font-size: 24px;
}
.advantage-card h3 {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--space-sm);
}
.advantage-card p {
  font-size: var(--text-sm);
  color: var(--text-secondary);
  line-height: 1.65;
}

/* --- Stats Bar --- */
.stats-bar {
  background: var(--color-primary);
  color: var(--text-inverse);
  padding: var(--space-3xl) 0;
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-xl);
  text-align: center;
}
.stat-item {}
.stat-number {
  font-size: var(--text-4xl);
  font-weight: 800;
  color: #FF6B6B;
  line-height: 1.2;
  margin-bottom: var(--space-xs);
}
.stat-label {
  font-size: var(--text-sm);
  opacity: 0.75;
  font-weight: 500;
}

/* --- Articles / Resources --- */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--space-lg);
}
.article-card {
  display: flex;
  flex-direction: column;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  text-decoration: none;
  transition: all var(--transition-base);
}
.article-card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}
.article-card-thumb {
  aspect-ratio: 16/9;
  background: var(--color-bg-alt);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: var(--text-sm);
  overflow: hidden;
}
.article-card-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.article-card-body { padding: var(--space-lg); }
.article-tag {
  display: inline-block;
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-accent);
  background: var(--color-accent-light);
  padding: 3px 10px;
  border-radius: var(--radius-full);
  margin-bottom: var(--space-sm);
}
.article-card-body h3 {
  font-size: var(--text-lg);
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: var(--space-sm);
  color: var(--text-primary);
  transition: color var(--transition-base);
}
.article-card:hover .article-card-body h3 { color: var(--color-accent); }
.article-card-body .meta {
  font-size: var(--text-xs);
  color: var(--text-muted);
  margin-top: var(--space-sm);
}

/* --- FAQ --- */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-sm);
  overflow: hidden;
}
.faq-question {
  width: 100%;
  padding: var(--space-lg);
  background: none;
  border: none;
  text-align: left;
  font-size: var(--text-base);
  font-weight: 600;
  color: var(--color-primary);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-md);
  transition: background var(--transition-fast);
}
.faq-question:hover { background: var(--color-bg); }
.faq-icon {
  font-size: var(--text-lg);
  color: var(--text-muted);
  transition: transform var(--transition-base);
  flex-shrink: 0;
}
.faq-item.open .faq-icon { transform: rotate(45deg); }
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-slow);
}
.faq-answer-inner {
  padding: 0 var(--space-lg) var(--space-lg);
  color: var(--text-secondary);
  font-size: var(--text-sm);
  line-height: 1.7;
}
.faq-item.open .faq-answer { max-height: 300px; }

/* --- Inquiry / Contact Form --- */
.inquiry-section {
  background: var(--color-primary);
  color: var(--text-inverse);
  padding: var(--space-4xl) 0;
}
.inquiry-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-3xl);
  align-items: start;
}
.inquiry-info h2 {
  font-size: var(--text-3xl);
  font-weight: 800;
  margin-bottom: var(--space-lg);
}
.inquiry-info > p {
  opacity: 0.8;
  line-height: 1.7;
  margin-bottom: var(--space-xl);
}
.contact-list { margin-bottom: var(--space-xl); }
.contact-item {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-md);
  font-size: var(--text-sm);
}
.contact-item-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  background: rgba(255,255,255,0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 14px;
}
.contact-item span { opacity: 0.9; }

.inquiry-form {
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
}
.inquiry-form h3 {
  font-size: var(--text-xl);
  font-weight: 700;
  margin-bottom: var(--space-lg);
}
.form-group { margin-bottom: var(--space-md); }
.form-group label {
  display: block;
  font-size: var(--text-sm);
  font-weight: 600;
  margin-bottom: 6px;
  opacity: 0.85;
}
.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 10px 14px;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.18);
  border-radius: var(--radius-md);
  color: var(--text-inverse);
  font-size: var(--text-sm);
  font-family: inherit;
  transition: border-color var(--transition-fast);
}
.form-group input::placeholder,
.form-group textarea::placeholder { color: rgba(255,255,255,0.35); }
.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--color-accent);
}
.form-group textarea { min-height: 100px; resize: vertical; }

/* 必填项：常驻红色边框作为必填标识 */
.form-group.required input,
.form-group.required textarea {
  border-color: #D71920;
}
.form-group.required input:focus,
.form-group.required textarea:focus {
  border-color: #D71920;
  box-shadow: 0 0 0 3px rgba(215, 25, 32, 0.15);
}
/* 字段提示文字（默认灰字，出错时变红） */
.field-hint {
  display: block;
  font-size: var(--text-xs);
  color: var(--text-muted);
  margin-top: 5px;
  line-height: 1.5;
}
.field-hint.error {
  color: #D71920;
  font-weight: 600;
}
/* 校验失败时的错误态（由 JS 添加） */
.form-group input.field-error,
.form-group textarea.field-error {
  border-color: #D71920 !important;
  box-shadow: 0 0 0 3px rgba(215, 25, 32, 0.18);
}

/* 表单提交状态提示 */
.form-status {
  display: none;
  margin-top: 14px;
  padding: 12px 16px;
  border-radius: var(--radius-md, 8px);
  font-size: var(--text-sm);
  line-height: 1.6;
  text-align: center;
}
.form-status.ok {
  display: block;
  background: rgba(22, 163, 74, 0.12);
  color: #15803d;
  border: 1px solid rgba(22, 163, 74, 0.35);
}
.form-status.error {
  display: block;
  background: rgba(215, 25, 32, 0.10);
  color: #D71920;
  border: 1px solid rgba(215, 25, 32, 0.30);
}
.form-status.pending {
  display: block;
  background: rgba(15, 23, 42, 0.06);
  color: var(--text-secondary, #475569);
  border: 1px solid rgba(15, 23, 42, 0.12);
}

.form-submit {
  width: 100%;
  padding: 12px;
  background: var(--color-accent);
  color: #FFF;
  border: none;
  border-radius: var(--radius-md);
  font-size: var(--text-base);
  font-weight: 700;
  cursor: pointer;
  transition: background var(--transition-fast);
}
.form-submit:hover { background: var(--color-accent-hover); }

/* --- Footer --- */
.footer {
  background: var(--color-primary);
  color: var(--text-inverse);
  padding: var(--space-3xl) 0 var(--space-xl);
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr 1fr;
  gap: var(--space-2xl);
  margin-bottom: var(--space-2xl);
}
.footer-brand p {
  font-size: var(--text-sm);
  opacity: 0.7;
  line-height: 1.7;
  margin-top: var(--space-md);
}
.footer-nav h4 {
  font-size: var(--text-sm);
  font-weight: 700;
  margin-bottom: var(--space-md);
  opacity: 0.9;
}
.footer-nav a {
  display: block;
  font-size: var(--text-sm);
  color: rgba(255,255,255,0.6);
  padding: 3px 0;
  transition: color var(--transition-fast);
}
.footer-nav a:hover { color: #FFF; opacity: 1; }
.footer-contact span { color: rgba(255,255,255,0.6); }
.footer-contact a, .footer-contact span { word-break: break-all; }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: var(--space-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}
.footer-disclaimer {
  margin: 0;
  font-size: 12px;
  line-height: 1.7;
  color: rgba(255,255,255,0.5);
  max-width: 960px;
}
.footer-bottom-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-md);
  font-size: var(--text-xs);
  color: rgba(255,255,255,0.5);
}

/* 公安备案号（页脚） */
.gongan-beian {
  display: inline-flex;
  align-items: center;
  gap: 4px;
}
.gongan-icon {
  vertical-align: middle;
}

/* --- Page Hero (inner pages) --- */
.page-hero {
  background: linear-gradient(135deg, #0A1628 0%, #1A2B45 100%);
  color: var(--text-inverse);
  padding: var(--space-3xl) 0;
}
.page-hero h1 {
  font-size: var(--text-4xl);
  font-weight: 800;
  margin-bottom: var(--space-sm);
}
.page-hero p {
  opacity: 0.75;
  font-size: var(--text-lg);
}
.breadcrumb {
  display: flex;
  gap: var(--space-sm);
  font-size: var(--text-sm);
  opacity: 0.6;
  margin-bottom: var(--space-lg);
}
.breadcrumb a { color: inherit; opacity: 0.8; }
.breadcrumb a:hover { opacity: 1; }
.breadcrumb .separator { opacity: 0.4; }

/* --- Brand Detail --- */
.brand-profile {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: var(--space-2xl);
  margin-top: calc(-1 * var(--space-3xl));
  position: relative;
  z-index: 2;
}
.brand-profile-sidebar {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  padding: var(--space-xl);
  text-align: center;
}
.brand-profile-logo {
  width: 100px;
  height: 100px;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-4xl);
  font-weight: 800;
  color: #FFF;
  margin: 0 auto var(--space-lg);
}
.brand-profile-logo-img {
  padding: 12px;
  border: 1px solid var(--color-border);
  box-sizing: border-box;
}
.brand-profile-logo-img img { width: 100%; height: 100%; object-fit: contain; }
.brand-profile-name {
  font-size: var(--text-xl);
  font-weight: 800;
  color: var(--color-primary);
  margin-bottom: 4px;
}
.brand-profile-origin {
  font-size: var(--text-sm);
  color: var(--text-muted);
  margin-bottom: var(--space-lg);
}
.brand-profile-tags { display: flex; flex-wrap: wrap; gap: 6px; justify-content: center; }
.tag {
  display: inline-block;
  font-size: var(--text-xs);
  font-weight: 500;
  padding: 4px 10px;
  border-radius: var(--radius-full);
  background: var(--color-bg);
  color: var(--text-secondary);
}

.brand-profile-main { }
.brand-section {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  margin-bottom: var(--space-lg);
}
.brand-section h2 {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-md);
  border-bottom: 1px solid var(--color-border-light);
}
.brand-desc { color: var(--text-secondary); line-height: 1.8; font-size: var(--text-sm); }
.brand-source-note {
  font-size: var(--text-xs);
  color: var(--text-muted);
  margin-top: var(--space-md);
}
.brand-disclaimer-block {
  margin-top: var(--space-lg);
  padding: var(--space-md) var(--space-lg);
  background: var(--color-bg);
  border: 1px solid var(--color-border-light);
  border-left: 3px solid var(--color-accent);
  border-radius: var(--radius-sm);
  font-size: var(--text-xs);
  line-height: 1.8;
  color: var(--text-muted);
}
.brand-disclaimer-block strong {
  color: var(--text-secondary);
  font-weight: 700;
}

.product-list-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-md) 0;
  border-bottom: 1px solid var(--color-border-light);
}
.product-list-item:last-child { border-bottom: none; }
.product-list-thumb {
  width: 72px;
  height: 72px;
  flex-shrink: 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--color-bg);
  border: 1px solid var(--color-border-light);
  display: flex;
  align-items: center;
  justify-content: center;
}
.product-list-thumb img { width: 100%; height: 100%; object-fit: contain; }
.product-list-body { flex: 1; min-width: 0; }
.product-list-item h4 { font-size: var(--text-base); font-weight: 600; }
.product-list-item h4 a { color: var(--text-primary); }
.product-list-item h4 a:hover { color: var(--color-accent); }
.product-code {
  font-size: var(--text-xs);
  font-family: var(--font-mono);
  color: var(--text-muted);
  background: var(--color-bg);
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  margin-left: var(--space-sm);
}
.product-desc { font-size: var(--text-sm); color: var(--text-secondary); margin-top: 4px; }
/* Product list grouped by family/series (show 1-2 per series) */
.product-family-group { margin-bottom: var(--space-2xl); }
.product-family-group:last-child { margin-bottom: 0; }
.product-family-title {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--space-sm);
  padding-bottom: var(--space-xs);
  border-bottom: 2px solid var(--color-border);
}
.product-family-more {
  margin-top: var(--space-sm);
  font-style: italic;
}
.btn-view-detail {
  font-size: var(--text-xs);
  padding: 4px 12px;
  flex-shrink: 0;
}

/* --- Product Detail --- */
.product-detail-grid {
  display: grid;
  grid-template-columns: 1fr 360px;
  gap: var(--space-2xl);
  margin-top: var(--space-2xl);
}
.product-main-info { }
.product-detail-hero {
  width: 100%;
  max-width: 520px;
  margin-bottom: var(--space-xl);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--color-bg);
  border: 1px solid var(--color-border-light);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-lg);
}
.product-detail-hero img { max-width: 100%; height: auto; max-height: 380px; object-fit: contain; }

/* Product detail rich sections */
.pd-badges { display: flex; align-items: center; gap: var(--space-md); margin-bottom: var(--space-lg); flex-wrap: wrap; }
.product-code {
  font-size: var(--text-xs);
  font-family: var(--font-mono);
  color: var(--text-muted);
  background: var(--color-bg);
  padding: 3px 10px;
  border-radius: var(--radius-sm);
}
.pd-section { margin-bottom: var(--space-2xl); }
.pd-section-title {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-sm);
  border-bottom: 2px solid var(--color-border-light);
}
.pd-features { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--space-sm) var(--space-lg); }
.pd-features li {
  position: relative;
  padding-left: 22px;
  font-size: var(--text-sm);
  color: var(--text-secondary);
  line-height: 1.7;
}
.pd-features li::before {
  content: '';
  position: absolute;
  left: 4px; top: 10px;
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--color-accent);
}
.pd-tags { display: flex; flex-wrap: wrap; gap: var(--space-sm); }
.pd-specnote { margin-top: var(--space-xl); }
.product-related { margin-top: var(--space-3xl); }
.product-related .pd-section-title { margin-bottom: var(--space-lg); }
.related-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--space-md); }
.related-card {
  display: block;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-md);
  text-decoration: none;
  color: inherit;
  transition: all var(--transition-base);
}
.related-card:hover { border-color: var(--color-accent); box-shadow: var(--shadow-lg); transform: translateY(-2px); }
.related-thumb {
  width: 100%; height: 120px;
  border-radius: var(--radius-md);
  background: var(--color-bg);
  border: 1px solid var(--color-border-light);
  display: flex; align-items: center; justify-content: center;
  margin-bottom: var(--space-sm); overflow: hidden;
}
.related-thumb img { width: 100%; height: 100%; object-fit: contain; }
.related-name { font-size: var(--text-sm); font-weight: 600; color: var(--color-primary); line-height: 1.4; }
.related-code { font-size: var(--text-xs); color: var(--text-muted); font-family: var(--font-mono); margin-top: 2px; }
.product-spec-table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--text-sm);
}
.product-spec-table th {
  text-align: left;
  background: var(--color-bg);
  padding: 10px 14px;
  font-weight: 600;
  color: var(--text-secondary);
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.product-spec-table td {
  padding: 10px 14px;
  border-bottom: 1px solid var(--color-border-light);
  color: var(--text-primary);
}
.product-sidebar { }
.sidebar-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  margin-bottom: var(--space-lg);
}
.sidebar-card h3 {
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-md);
}

/* --- Category Cards (products page) --- */
.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: var(--space-lg);
}
.category-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  text-align: center;
  transition: all var(--transition-base);
  cursor: pointer;
}
.category-card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}
.category-icon {
  font-size: 36px;
  margin-bottom: var(--space-md);
}
.category-card h3 {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 4px;
}
.category-card p {
  font-size: var(--text-sm);
  color: var(--text-muted);
}

/* --- Article Detail --- */
.article-content {
  max-width: 800px;
  margin: var(--space-2xl) auto;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-2xl) var(--space-3xl);
}
.article-cover {
  margin: 0 0 var(--space-2xl);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--color-border-light);
}
.article-cover img {
  width: 100%;
  display: block;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}
.article-cover figcaption {
  padding: var(--space-sm) var(--space-md);
  background: var(--color-bg-alt);
  font-size: var(--text-xs);
  color: var(--text-muted);
  text-align: center;
  line-height: 1.6;
}
.article-content h2 {
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--color-primary);
  margin: var(--space-2xl) 0 var(--space-lg);
}
.article-content h3 {
  font-size: var(--text-xl);
  font-weight: 600;
  color: var(--color-primary);
  margin: var(--space-xl) 0 var(--space-md);
}
.article-content p {
  color: var(--text-secondary);
  line-height: 1.85;
  margin-bottom: var(--space-md);
  font-size: var(--text-base);
}
.article-content ul, .article-content ol {
  padding-left: var(--space-lg);
  margin-bottom: var(--space-md);
}
.article-content li {
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 6px;
  list-style: disc;
}
.key-point {
  background: var(--color-accent-light);
  border-left: 4px solid var(--color-accent);
  padding: var(--space-lg);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin: var(--space-xl) 0;
  font-size: var(--text-sm);
  color: var(--text-primary);
}
.disclaimer-block {
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  margin-top: var(--space-2xl);
  font-size: var(--text-xs);
  color: var(--text-muted);
  line-height: 1.7;
}
.spec-table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-xl) 0;
  font-size: var(--text-sm);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
}
.spec-table th, .spec-table td {
  padding: var(--space-md) var(--space-lg);
  text-align: left;
  border-bottom: 1px solid var(--color-border);
  color: var(--text-primary);
  vertical-align: top;
}
.spec-table thead th {
  background: var(--color-primary);
  color: #fff;
  font-weight: 600;
}
.spec-table tbody tr:nth-child(even) { background: var(--color-bg-alt); }
.spec-table tbody tr:last-child td { border-bottom: none; }

/* --- Search & Filter bar --- */
.filter-bar {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  margin-bottom: var(--space-xl);
  display: flex;
  gap: var(--space-md);
  align-items: center;
  flex-wrap: wrap;
}
.search-input {
  flex: 1;
  min-width: 200px;
  padding: 10px 16px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-family: inherit;
  transition: border-color var(--transition-fast);
}
.search-input:focus { outline: none; border-color: var(--color-accent); }
.filter-chips { display: flex; gap: 6px; flex-wrap: wrap; }
.filter-chip {
  font-size: var(--text-xs);
  font-weight: 500;
  padding: 6px 14px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  background: transparent;
  cursor: pointer;
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}
.filter-chip:hover,
.filter-chip.active {
  border-color: var(--color-accent);
  color: var(--color-accent);
  background: var(--color-accent-light);
}

/* --- About page --- */
.about-intro {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-3xl);
  align-items: center;
}
.about-text h2 {
  font-size: var(--text-3xl);
  font-weight: 800;
  color: var(--color-primary);
  margin-bottom: var(--space-lg);
}
.about-text p {
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: var(--space-md);
}
.about-values {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-lg);
  margin-top: var(--space-3xl);
}
.value-card {
  text-align: center;
  padding: var(--space-xl);
}
.value-card .icon {
  font-size: 36px;
  margin-bottom: var(--space-md);
}
.value-card h3 {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--space-sm);
}
.value-card p {
  font-size: var(--text-sm);
  color: var(--text-secondary);
}

/* --- Contact page --- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-2xl);
}
.contact-form-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
}
.contact-form-card h2 {
  font-size: var(--text-2xl);
  font-weight: 700;
  margin-bottom: var(--space-lg);
}
/* 联系页表单在浅色卡片上，输入框必须用深色文字 + 实底背景（覆盖全局 .form-group 的深色主题样式） */
.contact-form-card .form-group input,
.contact-form-card .form-group select,
.contact-form-card .form-group textarea {
  background: #FFFFFF;
  border: 1px solid var(--color-border);
  color: var(--text-primary);
}
.contact-form-card .form-group input::placeholder,
.contact-form-card .form-group textarea::placeholder {
  color: var(--text-muted);
}
/* 必填项标记：标签后红色星号（由 CSS 自动生成，不受 i18n 文本覆盖影响，中英文均稳定显示） */
.contact-form-card .form-group.required > label::after {
  content: " *";
  color: #D71920;
  font-weight: 700;
}
.contact-details-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
}
.contact-detail-item {
  display: flex;
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-lg);
  border-bottom: 1px solid var(--color-border-light);
}
.contact-detail-item:last-child { border-bottom: none; margin-bottom: 0; padding-bottom: 0; }
.detail-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: var(--color-accent-light);
  color: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 18px;
}
.detail-label { font-size: var(--text-xs); color: var(--text-muted); font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em; }
.detail-value { font-size: var(--text-base); font-weight: 600; color: var(--color-primary); margin-top: 2px; }

/* --- Privacy page --- */
.privacy-content {
  max-width: 800px;
  margin: 0 auto;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-2xl) var(--space-3xl);
}
.privacy-content h2 {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-primary);
  margin: var(--space-xl) 0 var(--space-md);
}
.privacy-content p {
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: var(--space-md);
  font-size: var(--text-sm);
}

/* --- Responsive --- */
@media (max-width: 1024px) {
  .hero-grid { grid-template-columns: 1fr; text-align: center; }
  .hero p { max-width: 100%; margin-left: auto; margin-right: auto; }
  .hero-ctas { justify-content: center; }
  .hero-image { max-width: 480px; margin: 0 auto; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
  .inquiry-grid { grid-template-columns: 1fr; }
  .brand-profile { grid-template-columns: 1fr; }
  .brand-profile-sidebar { max-width: 360px; margin: 0 auto; }
  .product-detail-grid { grid-template-columns: 1fr; }
  .pd-features { grid-template-columns: 1fr; }
  .related-grid { grid-template-columns: repeat(2, 1fr); }
  .about-intro { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .about-values { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  :root { --header-height: 60px; }
  .header-nav { display: none; }
  .header-nav.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--color-surface);
    padding: var(--space-lg);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-lg);
    gap: 0;
  }
  .header-nav.open a { padding: var(--space-md) 0; }
  .mobile-menu-btn { display: block; }
  .hero h1 { font-size: var(--text-3xl); }
  .section-header h2 { font-size: var(--text-2xl); }
  .section { padding: var(--space-2xl) 0; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: var(--space-lg); }
  .brand-grid { grid-template-columns: 1fr; }
  .advantages-grid { grid-template-columns: 1fr; }
  .articles-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; text-align: center; }
  .footer-bottom { text-align: center; gap: var(--space-sm); }
  .footer-disclaimer { margin-left: auto; margin-right: auto; }
  .filter-bar { flex-direction: column; align-items: stretch; }
  .category-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 480px) {
  .container { padding: 0 var(--space-md); }
  .hero { padding: var(--space-2xl) 0; }
  .hero h1 { font-size: var(--text-2xl); }
  .brand-card { flex-direction: column; text-align: center; }
  .brand-card-logo { margin: 0 auto; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
  .stat-number { font-size: var(--text-2xl); }
}