/* ============================================
   郑州诺威耐火材料有限公司 — Design System
   ============================================ */



/* ---------- CSS Variables ---------- */
:root {
  /* Primary Colors */
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-primary-light: #3b82f6;
  
  /* Accent Colors */
  --color-accent: #2563eb;
  --color-accent-dark: #1d4ed8;
  --color-accent-light: #3b82f6;
  
  /* Neutral Colors */
  --color-bg-dark: #ffffff;
  --color-bg-section: #f5f7fa;
  --color-bg-card: #ffffff;
  --color-bg-card-hover: #f0f4ff;
  --color-surface: #f8fafc;
  --color-border: rgba(0, 0, 0, 0.08);
  --color-border-light: rgba(0, 0, 0, 0.12);
  
  /* Text Colors */
  --color-text: #334155;
  --color-text-secondary: #64748b;
  --color-text-muted: #94a3b8;
  --color-text-white: #1e293b;
  
  /* Functional */
  --color-success: #16a34a;
  --color-error: #dc2626;
  
  /* Typography */
  --font-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --font-display: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  
  /* 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 */
  --container-max: 1320px;
  --container-wide: 1400px;
  --nav-height: 70px;
  --top-bar-height: 0px;
  
  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.12);
  --shadow-glow: 0 0 20px rgba(37, 99, 235, 0.15);
  
  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-base: 0.3s ease;
  --transition-slow: 0.5s ease;
  
  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 20px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-primary);
  color: var(--color-text);
  background: #ffffff;
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

ul, ol {
  list-style: none;
}

button {
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
  font-size: inherit;
  color: inherit;
}

input, textarea, select {
  font-family: inherit;
  font-size: inherit;
}

/* ---------- Container ---------- */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-xl);
}

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

/* ---------- Top Info Bar ---------- */
.top-bar {
  display: none;
}

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

.top-bar__contact {
  display: flex;
  gap: var(--space-xl);
  align-items: center;
}

.top-bar__contact a {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  color: rgba(255, 255, 255, 0.85);
}

.top-bar__contact a:hover {
  color: var(--color-accent-light);
}

.top-bar__social {
  display: flex;
  gap: var(--space-md);
  align-items: center;
}

/* ---------- Navigation ---------- */
.navbar {
  position: fixed;
  top: var(--top-bar-height);
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border);
  z-index: 1000;
  transition: all var(--transition-base);
}

.navbar.scrolled {
  top: 0;
  background: rgba(255, 255, 255, 0.98);
  box-shadow: var(--shadow-md);
}

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

.navbar__logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--color-text-white);
  white-space: nowrap;
}

.navbar__logo-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, #2563eb, #1d4ed8);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 1.1rem;
  color: white;
  flex-shrink: 0;
}

.navbar__logo-img {
  height: 40px;
  width: auto;
  flex-shrink: 0;
  object-fit: contain;
  display: inline-block;
}

.footer__logo-img {
  height: 36px;
  width: auto;
  flex-shrink: 0;
  object-fit: contain;
  display: inline-block;
}

.navbar__menu {
  display: flex;
  gap: 0;
  align-items: center;
  height: 100%;
}

.navbar__item {
  position: relative;
  height: 100%;
  display: flex;
  align-items: center;
}

.navbar__link {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 0 var(--space-md);
  height: 100%;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-text);
  transition: color var(--transition-fast);
  position: relative;
}

.navbar__link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 0;
  height: 2px;
  background: var(--color-accent);
  transition: width var(--transition-base);
}

.navbar__link:hover,
.navbar__link.active {
  color: var(--color-accent-light);
}

.navbar__link:hover::after,
.navbar__link.active::after {
  width: 60%;
}

.navbar__link .arrow {
  font-size: 0.6rem;
  transition: transform var(--transition-fast);
}

.navbar__item:hover .arrow {
  transform: rotate(180deg);
}

/* Dropdown */
.navbar__dropdown {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(10px);
  min-width: 200px;
  background: #ffffff;
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
  padding: var(--space-sm) 0;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
  box-shadow: var(--shadow-lg);
}

.navbar__item:hover .navbar__dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

.navbar__dropdown a {
  display: block;
  padding: var(--space-sm) var(--space-lg);
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  transition: all var(--transition-fast);
}

.navbar__dropdown a:hover {
  background: rgba(37, 99, 235, 0.06);
  color: var(--color-primary);
  padding-left: var(--space-xl);
}

/* Mobile Hamburger */
.navbar__toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--space-sm);
  cursor: pointer;
}

.navbar__toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: #334155;
  transition: all var(--transition-base);
}

.navbar__toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.navbar__toggle.active span:nth-child(2) {
  opacity: 0;
}

.navbar__toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ---------- Section Styles ---------- */
.section {
  padding: var(--space-4xl) 0;
}

.section--dark {
  background: var(--color-bg-section);
}

.section__header {
  text-align: center;
  margin-bottom: var(--space-3xl);
}

.section__title {
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--color-text-white);
  margin-bottom: var(--space-sm);
  position: relative;
  display: inline-block;
}

.section__title::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--color-accent), var(--color-primary-light));
  border-radius: 2px;
}

.section__subtitle {
  font-size: 0.95rem;
  color: var(--color-text-muted);
  margin-top: var(--space-lg);
  letter-spacing: 2px;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 0.75rem 2rem;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 0.95rem;
  transition: all var(--transition-base);
  cursor: pointer;
  border: none;
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.15), transparent);
  transition: left 0.5s ease;
}

.btn:hover::before {
  left: 100%;
}

.btn-primary {
  background: linear-gradient(135deg, #2563eb, #1d4ed8);
  color: white;
  box-shadow: 0 4px 15px rgba(37, 99, 235, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 25px rgba(37, 99, 235, 0.4);
}

.btn-outline {
  border: 2px solid #2563eb;
  color: #2563eb;
  background: transparent;
}

.btn-outline:hover {
  background: #2563eb;
  color: white;
  transform: translateY(-2px);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.08);
  color: var(--color-text);
  border: 1px solid var(--color-border-light);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: var(--color-accent);
  color: var(--color-accent-light);
}

/* ---------- Cards ---------- */
.card {
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-base);
  box-shadow: var(--shadow-sm);
}

.card:hover {
  transform: translateY(-8px);
  border-color: var(--color-primary);
  box-shadow: 0 8px 30px rgba(37, 99, 235, 0.12);
}

.card__image {
  width: 100%;
  height: 220px;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.card:hover .card__image {
  transform: scale(1.05);
}

.card__image-wrapper {
  overflow: hidden;
  position: relative;
}

.card__image-wrapper::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 60px;
  background: linear-gradient(transparent, #ffffff);
}

.card__body {
  padding: var(--space-lg);
}

.card__title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--color-text-white);
  margin-bottom: var(--space-sm);
}

.card__text {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

.card__footer {
  padding: 0 var(--space-lg) var(--space-lg);
}

/* ---------- Footer ---------- */
.footer {
  background: linear-gradient(180deg, #f1f5f9, #e2e8f0);
  border-top: 1px solid var(--color-border);
  padding-top: var(--space-4xl);
}

.footer__grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: var(--space-3xl);
  padding-bottom: var(--space-3xl);
}

.footer__brand {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.footer__brand-name {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--color-text-white);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.footer__brand-desc {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  line-height: 1.8;
}

.footer__title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text-white);
  margin-bottom: var(--space-lg);
  position: relative;
  padding-bottom: var(--space-sm);
}

.footer__title::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 30px;
  height: 2px;
  background: var(--color-accent);
}

.footer__links {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.footer__links a {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.footer__links a:hover {
  color: var(--color-accent-light);
  transform: translateX(4px);
}

.footer__links a::before {
  content: '›';
  color: var(--color-accent);
  font-weight: bold;
}

.footer__contact-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
  font-size: 0.9rem;
  color: var(--color-text-secondary);
}

.footer__contact-icon {
  color: var(--color-accent);
  font-size: 1rem;
  margin-top: 2px;
  flex-shrink: 0;
}

.footer__bottom {
  border-top: 1px solid var(--color-border);
  padding: var(--space-lg) 0;
  text-align: center;
  font-size: 0.8rem;
  color: #475569;
}

.footer__bottom a {
  color: #475569;
  text-decoration: none;
  transition: color 0.2s;
}

.footer__bottom a:hover {
  color: var(--color-primary);
  text-decoration: underline;
}

/* ---------- Page Banner ---------- */
.page-banner {
  height: 300px;
  background-size: cover;
  background-position: center;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: calc(var(--top-bar-height) + var(--nav-height));
}

.page-banner::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(15, 23, 42, 0.82), rgba(30, 58, 138, 0.7));
}

.page-banner__content {
  position: relative;
  text-align: center;
  z-index: 1;
}

.page-banner__title {
  font-size: 2.8rem;
  font-weight: 800;
  color: #ffffff;
  margin-bottom: var(--space-md);
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
  letter-spacing: 2px;
}

.page-banner__title::after {
  content: '';
  display: block;
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, #60a5fa, #3b82f6);
  margin: var(--space-md) auto 0;
  border-radius: 2px;
}

.page-banner__breadcrumb {
  font-size: 0.95rem;
  color: rgba(255, 255, 255, 0.75);
  margin-top: var(--space-md);
  letter-spacing: 1px;
}

.page-banner__breadcrumb a {
  color: rgba(255, 255, 255, 0.9);
  font-weight: 500;
  transition: color 0.2s ease;
}

.page-banner__breadcrumb a:hover {
  color: #93c5fd;
  text-decoration: underline;
}

/* ---------- Back to Top ---------- */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 45px;
  height: 45px;
  background: linear-gradient(135deg, #2563eb, #1d4ed8);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: all var(--transition-base);
  z-index: 999;
  box-shadow: 0 4px 15px rgba(37, 99, 235, 0.3);
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  transform: translateY(-4px);
  box-shadow: 0 6px 25px rgba(37, 99, 235, 0.4);
}

/* ---------- Scroll Animations ---------- */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

.fade-in-left {
  opacity: 0;
  transform: translateX(-40px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in-left.visible {
  opacity: 1;
  transform: translateX(0);
}

.fade-in-right {
  opacity: 0;
  transform: translateX(40px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in-right.visible {
  opacity: 1;
  transform: translateX(0);
}

/* ---------- Language Switcher ---------- */
.lang-switch {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 6px 14px;
  border: 1px solid var(--color-border-light);
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--color-text);
  background: transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  white-space: nowrap;
  margin-left: var(--space-md);
}

.lang-switch:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background: rgba(37, 99, 235, 0.05);
}

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
  .footer__grid {
    grid-template-columns: 1fr 1fr;
  }
  
  .section__title {
    font-size: 1.8rem;
  }
}

@media (max-width: 768px) {
  :root {
    --nav-height: 60px;
    --top-bar-height: 0px;
  }
  
  .top-bar {
    display: none;
  }
  
  .navbar {
    top: 0;
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    background: #ffffff;
  }
  
  .navbar .container {
    position: relative;
  }
  
  .navbar__toggle {
    display: flex;
    flex-shrink: 0;
  }
  
  .navbar__menu {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    bottom: 0;
    background: #ffffff;
    flex-direction: column;
    padding: var(--space-lg) var(--space-xl);
    gap: 0;
    overflow-y: auto;
    transform: translateX(100%);
    transition: transform var(--transition-base);
    z-index: 9999;
  }
  
  .navbar__menu.active {
    transform: translateX(0);
  }
  
  .navbar__item {
    width: 100%;
    height: auto;
    flex-direction: column;
  }
  
  .navbar__link {
    padding: var(--space-lg) 0;
    width: 100%;
    justify-content: space-between;
    height: auto;
    border-bottom: 1px solid var(--color-border);
    color: #1e293b;
    font-size: 1rem;
  }

  .navbar__link:hover,
  .navbar__link.active {
    color: #2563eb;
  }
  
  .navbar__link::after {
    display: none;
  }

  .navbar__link .arrow {
    font-size: 0.7rem;
    transition: transform 0.3s ease;
  }

  .navbar__item.open .arrow {
    transform: rotate(180deg);
  }
  
  .navbar__dropdown {
    position: static !important;
    transform: none !important;
    left: auto;
    top: auto;
    min-width: 0;
    opacity: 1;
    visibility: visible;
    background: #f8fafc;
    border: none;
    border-radius: var(--radius-md);
    box-shadow: none;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    padding: 0;
    width: 100%;
  }
  
  .navbar__item:hover .navbar__dropdown {
    transform: none !important;
  }

  .navbar__item.open .navbar__dropdown {
    max-height: 500px;
    padding: var(--space-sm) 0;
  }

  .navbar__dropdown a {
    padding: var(--space-md) var(--space-xl);
    font-size: 0.95rem;
    color: #475569;
  }

  .navbar__dropdown a:hover {
    color: #2563eb;
    padding-left: var(--space-2xl);
  }

  .lang-switch {
    position: absolute;
    right: calc(var(--space-md) + 44px);
    top: 50%;
    transform: translateY(-50%);
    margin: 0;
    padding: 4px 10px;
    font-size: 0.8rem;
    border-color: #cbd5e1;
  }
  
  .footer__grid {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }
  
  .page-banner {
    height: 200px;
  }
  
  .page-banner__title {
    font-size: 1.8rem;
  }
  
  .section {
    padding: var(--space-3xl) 0;
  }
  
  .container {
    padding: 0 var(--space-md);
  }
}

@media (max-width: 480px) {
  .section__title {
    font-size: 1.5rem;
  }
  
  .btn {
    padding: 0.6rem 1.5rem;
    font-size: 0.85rem;
  }
}