/* ========================================
   纽辰生物官网 - 主样式表
   参考: Opentrons.com 风格
   ======================================== */

/* CSS Variables */
:root {
  --primary: #0066CC;
  --primary-dark: #003366;
  --accent: #FF6600;
  --bg-light: #F8FAFC;
  --bg-white: #FFFFFF;
  --text-primary: #1A1A2E;
  --text-secondary: #64748B;
  --border: #E2E8F0;
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --radius: 12px;
  --radius-sm: 8px;
  --transition: all 0.3s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Segoe UI', Roboto, sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg-white);
}

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

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

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

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ========================================
   Navigation
   ======================================== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: var(--bg-white);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
  height: 72px;
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 32px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text-primary);
}

.logo-img {
  height: 40px;
  width: auto;
}

.footer-logo .logo-img {
  height: 48px;
}

.logo-mark {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 700;
  font-size: 0.875rem;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-menu a {
  color: var(--text-secondary);
  font-weight: 500;
  padding: 8px 0;
  border-bottom: 2px solid transparent;
}

.nav-menu a:hover {
  color: var(--primary);
  border-bottom-color: var(--primary);
}

.nav-cta {
  display: flex;
  gap: 12px;
}

/* Mobile Nav Toggle */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

/* ========================================
   Buttons
   ======================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.9375rem;
  cursor: pointer;
  transition: var(--transition);
  border: none;
}

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

.btn-primary:hover {
  background: var(--primary-dark);
  color: white;
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--primary);
  color: var(--primary);
}

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

.btn-large {
  padding: 16px 32px;
  font-size: 1rem;
}

/* ========================================
   Hero Section
   ======================================== */
.hero {
  padding: 160px 0 100px;
  background: linear-gradient(180deg, var(--bg-light) 0%, var(--bg-white) 100%);
  text-align: center;
}

.hero-badge {
  display: inline-block;
  background: rgba(0, 102, 204, 0.1);
  color: var(--primary);
  padding: 8px 16px;
  border-radius: 20px;
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 24px;
}

.hero h1 {
  font-size: clamp(2.5rem, 5vw, 3.5rem);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.hero h1 span {
  color: var(--primary);
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 40px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ========================================
   Section Styles
   ======================================== */
.section {
  padding: 100px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-header h2 {
  font-size: 2.25rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.section-header p {
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

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

/* ========================================
   Features Grid
   ======================================== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 24px;
}

.feature-card {
  background: var(--bg-white);
  padding: 32px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  transition: var(--transition);
}

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

.feature-icon {
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, rgba(0, 102, 204, 0.1), rgba(0, 102, 204, 0.2));
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  font-size: 1.5rem;
}

.feature-card h3 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 0.9375rem;
}

/* ========================================
   Workflow Section
   ======================================== */
.workflow {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  padding: 60px 0;
}

.workflow-step {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 24px;
  background: var(--bg-white);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  min-width: 200px;
}

.workflow-step-icon {
  width: 64px;
  height: 64px;
  background: var(--primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.5rem;
  margin-bottom: 16px;
}

.workflow-step h4 {
  font-size: 1rem;
  margin-bottom: 8px;
}

.workflow-step p {
  color: var(--text-secondary);
  font-size: 0.875rem;
}

.workflow-arrow {
  color: var(--primary);
  font-size: 1.5rem;
  font-weight: 300;
}

/* ========================================
   Products Grid
   ======================================== */
.products-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 32px;
}

.product-card {
  background: var(--bg-white);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: var(--transition);
}

.product-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

.product-image {
  height: 220px;
  background: linear-gradient(135deg, #E8F4FD, #D1E9FB);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  font-size: 3rem;
}

.product-content {
  padding: 28px;
}

.product-tag {
  display: inline-block;
  background: rgba(0, 102, 204, 0.1);
  color: var(--primary);
  padding: 4px 12px;
  border-radius: 12px;
  font-size: 0.75rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.product-card h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.product-card p {
  color: var(--text-secondary);
  margin-bottom: 20px;
  font-size: 0.9375rem;
}

.product-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--primary);
  font-weight: 600;
  font-size: 0.9375rem;
}

.product-link:hover {
  gap: 10px;
}

/* ========================================
   Stats Section
   ======================================== */
.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 32px;
  text-align: center;
  padding: 60px 0;
}

.stat-item h3 {
  font-size: 3rem;
  font-weight: 800;
  color: var(--primary);
  margin-bottom: 8px;
}

.stat-item p {
  color: var(--text-secondary);
  font-weight: 500;
}

/* ========================================
   CTA Section
   ======================================== */
.cta-section {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: white;
  text-align: center;
  padding: 80px 0;
}

.cta-section h2 {
  font-size: 2rem;
  margin-bottom: 16px;
}

.cta-section p {
  opacity: 0.9;
  margin-bottom: 32px;
  max-width: 500px;
  margin-left: auto;
  margin-right: auto;
}

.cta-section .btn {
  background: white;
  color: var(--primary);
}

.cta-section .btn:hover {
  background: var(--bg-light);
}

/* ========================================
   Footer
   ======================================== */
.footer {
  background: var(--text-primary);
  color: white;
  padding: 60px 0 30px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand p {
  color: rgba(255, 255, 255, 0.7);
  margin-top: 16px;
  font-size: 0.9375rem;
}

.footer-column h4 {
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 20px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: rgba(255, 255, 255, 0.5);
}

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

.footer-column li {
  margin-bottom: 12px;
}

.footer-column a {
  color: rgba(255, 255, 255, 0.8);
  font-size: 0.9375rem;
}

.footer-column a:hover {
  color: white;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 30px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: rgba(255, 255, 255, 0.5);
  font-size: 0.875rem;
}

/* ========================================
   Page Header (Inner Pages)
   ======================================== */
.page-header {
  background: var(--bg-light);
  padding: 140px 0 60px;
  text-align: center;
}

.page-header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.breadcrumb {
  display: flex;
  justify-content: center;
  gap: 8px;
  color: var(--text-secondary);
  font-size: 0.9375rem;
}

.breadcrumb a {
  color: var(--text-secondary);
}

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

/* ========================================
   Product Detail Page
   ======================================== */
.product-detail {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: start;
}

.product-gallery {
  background: var(--bg-light);
  border-radius: var(--radius);
  padding: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 400px;
}

.product-gallery-placeholder {
  font-size: 6rem;
  color: var(--primary);
}

.product-info h1 {
  font-size: 2rem;
  margin-bottom: 16px;
}

.product-info .product-tag {
  margin-bottom: 16px;
}

.product-description {
  color: var(--text-secondary);
  font-size: 1.0625rem;
  line-height: 1.7;
  margin-bottom: 32px;
}

.product-actions {
  display: flex;
  gap: 16px;
  margin-bottom: 40px;
}

.spec-table {
  width: 100%;
  border-collapse: collapse;
}

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

.spec-table th {
  color: var(--text-secondary);
  font-weight: 500;
  width: 40%;
}

/* ========================================
   Responsive Design
   ======================================== */
@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .product-detail {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .nav-menu {
    display: none;
    position: absolute;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--bg-white);
    flex-direction: column;
    padding: 24px;
    gap: 16px;
    border-bottom: 1px solid var(--border);
  }
  
  .nav-menu.active {
    display: flex;
  }
  
  .nav-toggle {
    display: block;
  }
  
  .nav-cta {
    display: none;
  }
  
  .hero {
    padding: 120px 0 60px;
  }
  
  .hero h1 {
    font-size: 2rem;
  }
  
  .hero-subtitle {
    font-size: 1rem;
  }
  
  .section {
    padding: 60px 0;
  }
  
  .section-header h2 {
    font-size: 1.75rem;
  }
  
  .workflow {
    flex-direction: column;
  }
  
  .workflow-arrow {
    transform: rotate(90deg);
  }
  
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  
  .footer-bottom {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }
}

/* ========================================
   Utility Classes
   ======================================== */
.text-center { text-align: center; }
.text-primary { color: var(--primary); }
.mt-4 { margin-top: 24px; }
.mb-4 { margin-bottom: 24px; }
.mb-6 { margin-bottom: 48px; }