:root {
  /* Colors */
  --primary-color: #0066CC;
  --secondary-color: #FFD700;
  --text-color: #333333;
  --text-light: #666666;
  --bg-color: #ffffff;
  --bg-light: #f5f7fa;
  --white: #ffffff;
  
  /* Spacing */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
  --spacing-xxl: 48px;
  
  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;
  
  /* Shadows */
  --shadow-sm: 0 2px 4px rgba(0,0,0,0.1);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
  
  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
}

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

body {
  font-family: "Microsoft YaHei", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--text-color);
  line-height: 1.6;
  background-color: var(--bg-color);
  -webkit-font-smoothing: antialiased;
}

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

ul {
  list-style: none;
}

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

/* Layout */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

section {
  padding: var(--spacing-xxl) 0;
}

.section-title {
  text-align: center;
  font-size: 2.5rem;
  font-weight: bold;
  margin-bottom: var(--spacing-sm);
  color: var(--primary-color);
}

.section-subtitle {
  text-align: center;
  color: var(--text-light);
  margin-bottom: var(--spacing-xl);
  font-size: 1.1rem;
}

/* Navbar */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background-color: var(--white);
  box-shadow: var(--shadow-sm);
  z-index: 1000;
  height: 70px;
  display: flex;
  align-items: center;
}

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

.logo {
  font-size: 1.5rem;
  font-weight: bold;
  color: var(--primary-color);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.nav-links {
  display: flex;
  gap: var(--spacing-lg);
}

.nav-links a {
  font-weight: 500;
  color: var(--text-color);
  padding: var(--spacing-xs) 0;
  position: relative;
}

.nav-links a:hover, .nav-links a.active {
  color: var(--primary-color);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--primary-color);
  transition: var(--transition-fast);
}

.nav-links a:hover::after, .nav-links a.active::after {
  width: 100%;
}

.mobile-menu-btn {
  display: none;
  font-size: 1.5rem;
  cursor: pointer;
}

/* Hero Section */
.hero {
  margin-top: 70px;
  height: 600px;
  position: relative;
  overflow: hidden;
}

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

.carousel-slide {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  transition: opacity 0.5s ease-in-out;
  background-size: cover;
  background-position: center;
}

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

.carousel-slide::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0.4);
}

.banner-slot img {
  width: 100%;
  display: block;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.hero-content {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
  color: var(--white);
  width: 90%;
  max-width: 800px;
  z-index: 10;
}

.hero-title {
  font-size: 3rem;
  margin-bottom: var(--spacing-md);
  font-weight: bold;
}

.hero-text {
  font-size: 1.25rem;
  margin-bottom: var(--spacing-xl);
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 12px 30px;
  border-radius: var(--radius-md);
  font-weight: bold;
  text-align: center;
  cursor: pointer;
  transition: var(--transition-normal);
  border: none;
}

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

.btn-primary:hover {
  background-color: #0052a3;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background-color: var(--secondary-color);
  color: var(--text-color);
}

.btn-secondary:hover {
  background-color: #e6c200;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

/* Cards */
.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-lg);
}

.card {
  background: var(--white);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition-normal);
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.card-image {
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.detail-image {
  width: 100%;
  max-height: 520px;
  object-fit: cover;
  display: block;
}

.detail-title {
  font-size: 2rem;
  margin: 0 0 var(--spacing-sm) 0;
}

.detail-meta {
  color: var(--text-light);
  margin-bottom: var(--spacing-md);
  font-size: 0.95rem;
}

.detail-description {
  white-space: pre-line;
  color: var(--text-color);
  line-height: 1.7;
}

.card-content {
  padding: var(--spacing-md);
}

.card-title {
  font-size: 1.25rem;
  margin-bottom: var(--spacing-sm);
  color: var(--text-color);
}

.card-text {
  color: var(--text-light);
  margin-bottom: var(--spacing-md);
  font-size: 0.95rem;
}

/* Footer */
.footer {
  background-color: #1a1a1a;
  color: #cccccc;
  padding: var(--spacing-xxl) 0 var(--spacing-md);
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
}

.footer-col h3 {
  color: var(--white);
  margin-bottom: var(--spacing-md);
  font-size: 1.1rem;
}

.footer-links li {
  margin-bottom: var(--spacing-sm);
}

.footer-links a:hover {
  color: var(--secondary-color);
}

.footer-bottom {
  border-top: 1px solid #333;
  padding-top: var(--spacing-md);
  text-align: center;
  font-size: 0.9rem;
}

.footer-bottom a {
  color: #999;
}

.footer-bottom a:hover {
  color: var(--white);
}

/* Utility */
.text-center { text-align: center; }
.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.mb-3 { margin-bottom: var(--spacing-lg); }

/* Contact Form */
.contact-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-xl);
}

.contact-info-item {
  display: flex;
  align-items: flex-start;
  margin-bottom: var(--spacing-lg);
}

.contact-icon {
  width: 50px;
  height: 50px;
  background-color: rgba(0, 102, 204, 0.1);
  color: var(--primary-color);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  margin-right: var(--spacing-md);
  flex-shrink: 0;
}

.form-group {
  margin-bottom: var(--spacing-md);
}

.form-label {
  display: block;
  margin-bottom: var(--spacing-xs);
  font-weight: 500;
}

.form-control {
  width: 100%;
  padding: 12px;
  border: 1px solid #ddd;
  border-radius: var(--radius-sm);
  font-family: inherit;
  transition: border-color 0.3s;
}

.form-control:focus {
  outline: none;
  border-color: var(--primary-color);
}

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

@media (max-width: 768px) {
  .contact-container {
    grid-template-columns: 1fr;
  }
}