/* 北京中大恒瑞科技 - 火山引擎代理商官网 样式 */
/* 模仿火山引擎风格，科技风创新设计 */

:root {
  --primary-blue: #165DFF;
  --secondary-blue: #4080FF;
  --dark-blue: #0E2B5C;
  --light-gray: #F5F7FA;
  --text-dark: #1D2129;
  --text-gray: #4E5969;
  --border-gray: #E5E6EB;
  --gradient-bg: linear-gradient(135deg, #165DFF 0%, #40A9FF 100%);
  --gradient-hero: linear-gradient(120deg, #0a1633 0%, #165DFF 100%);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.12);
  --shadow-lg: 0 8px 24px rgba(22, 93, 255, 0.15);
  --transition: all 0.3s ease;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--text-dark);
  line-height: 1.6;
  background-color: #fff;
}

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

/* 导航栏 */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-sm);
  z-index: 1000;
  transition: var(--transition);
}

.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
}

.logo {
  font-size: 22px;
  font-weight: 700;
  color: var(--primary-blue);
  text-decoration: none;
  display: flex;
  align-items: center;
}

.logo img {
  height: 40px;
  margin-right: 10px;
}

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

.nav-menu a {
  text-decoration: none;
  color: var(--text-dark);
  font-size: 15px;
  font-weight: 500;
  transition: var(--transition);
  position: relative;
}

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

.nav-menu a:hover::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--primary-blue);
  border-radius: 1px;
}

.contact-btn {
  background: var(--gradient-bg);
  color: white;
  padding: 10px 24px;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 500;
  transition: var(--transition);
  border: none;
  cursor: pointer;
}

.contact-btn:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

/* Hero区域 */
.hero {
  margin-top: 70px;
  background: var(--gradient-hero);
  color: white;
  padding: 120px 0;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    radial-gradient(circle at 20% 80%, rgba(120, 119, 198, 0.3) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(255, 255, 255, 0.2) 0%, transparent 50%),
    radial-gradient(circle at 40% 40%, rgba(120, 198, 255, 0.2) 0%, transparent 50%);
  opacity: 0.6;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 700px;
}

.hero h1 {
  font-size: 48px;
  font-weight: 700;
  margin-bottom: 16px;
  line-height: 1.2;
}

.hero p {
  font-size: 20px;
  opacity: 0.9;
  margin-bottom: 32px;
  line-height: 1.6;
}

.hero-buttons {
  display: flex;
  gap: 16px;
}

.btn-primary {
  background: white;
  color: var(--primary-blue);
  padding: 14px 32px;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 600;
  transition: var(--transition);
  display: inline-block;
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 20px rgba(0,0,0,0.2);
}

.btn-secondary {
  background: transparent;
  color: white;
  border: 2px solid white;
  padding: 14px 32px;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 600;
  transition: var(--transition);
  display: inline-block;
}

.btn-secondary:hover {
  background: white;
  color: var(--primary-blue);
  transform: translateY(-3px);
}

/* 产品区块 */
.section {
  padding: 80px 0;
}

.section-title {
  text-align: center;
  font-size: 36px;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-dark);
}

.section-subtitle {
  text-align: center;
  font-size: 16px;
  color: var(--text-gray);
  margin-bottom: 60px;
}

.product-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 30px;
}

.product-card {
  background: white;
  border-radius: 8px;
  padding: 30px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-gray);
  transition: var(--transition);
}

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

.product-card .icon {
  width: 60px;
  height: 60px;
  background: var(--gradient-bg);
  border-radius: 12px;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 28px;
}

.product-card h3 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--text-dark);
}

.product-card p {
  color: var(--text-gray);
  margin-bottom: 20px;
  font-size: 14px;
  line-height: 1.7;
}

.product-card .link {
  color: var(--primary-blue);
  text-decoration: none;
  font-weight: 500;
  font-size: 15px;
  display: inline-flex;
  align-items: center;
  transition: var(--transition);
}

.product-card .link:hover {
  gap: 8px;
}

.highlight-badge {
  display: inline-block;
  background: #E8FFEA;
  color: #00B42A;
  padding: 4px 10px;
  border-radius: 4px;
  font-size: 12px;
  font-weight: 500;
  margin-bottom: 10px;
}

/* 优势区块 */
.features {
  background: var(--light-gray);
}

.feature-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 40px;
}

.feature-item {
  text-align: center;
  padding: 30px;
}

.feature-item .icon {
  width: 80px;
  height: 80px;
  margin: 0 auto 20px;
  background: var(--gradient-bg);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 36px;
}

.feature-item h3 {
  font-size: 18px;
  margin-bottom: 10px;
}

.feature-item p {
  color: var(--text-gray);
  font-size: 14px;
}

/* 页脚 */
.footer {
  background: var(--dark-blue);
  color: rgba(255, 255, 255, 0.7);
  padding: 60px 0 30px;
}

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

.footer-col h4 {
  color: white;
  font-size: 16px;
  margin-bottom: 20px;
}

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

.footer-col ul li {
  margin-bottom: 10px;
}

.footer-col ul li a {
  color: rgba(255, 255, 255, 0.7);
  text-decoration: none;
  transition: var(--transition);
  font-size: 14px;
}

.footer-col ul li a:hover {
  color: white;
  padding-left: 4px;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 30px;
  text-align: center;
  font-size: 14px;
}

/* 页面标题栏（内页） */
.page-header {
  margin-top: 70px;
  background: var(--gradient-hero);
  color: white;
  padding: 60px 0;
  text-align: center;
}

.page-header h1 {
  font-size: 40px;
  margin-bottom: 12px;
}

.page-header p {
  font-size: 18px;
  opacity: 0.9;
}

.content-section {
  padding: 60px 0;
}

.content-text {
  max-width: 900px;
  margin: 0 auto;
  color: var(--text-gray);
  line-height: 1.8;
}

.content-text h2 {
  color: var(--text-dark);
  font-size: 28px;
  margin: 30px 0 16px;
}

.content-text p {
  margin-bottom: 16px;
}

/* 联系表单 */
.contact-form {
  max-width: 600px;
  margin: 0 auto;
}

.form-group {
  margin-bottom: 24px;
}

.form-group label {
  display: block;
  margin-bottom: 8px;
  font-weight: 500;
  color: var(--text-dark);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--border-gray);
  border-radius: 6px;
  font-size: 15px;
  transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--primary-blue);
  box-shadow: 0 0 0 3px rgba(22, 93, 255, 0.1);
}

/* 响应式 */
/* 移动端汉堡菜单 */
.mobile-menu-btn {
  display: none;
  width: 40px;
  height: 30px;
  background: transparent;
  border: none;
  cursor: pointer;
  flex-direction: column;
  justify-content: space-between;
  padding: 0;
}

.mobile-menu-btn span {
  display: block;
  width: 100%;
  height: 3px;
  background: var(--primary-blue);
  border-radius: 2px;
  transition: var(--transition);
}

.mobile-menu-overlay {
  display: none;
  position: fixed;
  top: 70px;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0,0,0,0);
  opacity: 0;
  z-index: 998;
}

.mobile-menu-overlay.active {
  display: block;
  opacity: 0.5;
}

.nav-menu.mobile-open {
  display: flex !important;
  position: fixed;
  top: 70px;
  right: 0;
  bottom: 0;
  width: 250px;
  background: white;
  flex-direction: column;
  padding: 20px;
  box-shadow: -4px 0 10px rgba(0,0,0,0.1);
  z-index: 999;
}

@media (max-width: 768px) {
  .mobile-menu-btn {
    display: flex;
  }
  
  .nav-menu {
    display: none;
  }
  
  .hero h1 {
    font-size: 32px;
  }
  
  .hero p {
    font-size: 16px;
  }
  
  .hero-buttons {
    flex-direction: column;
    gap: 12px;
  }
  
  .hero-buttons .btn-primary,
  .hero-buttons .btn-secondary {
    width: 100%;
    text-align: center;
    padding: 12px 20px;
    font-size: 16px;
  }
  
  .product-grid {
    grid-template-columns: 1fr;
  }
  
  .footer-content {
    grid-template-columns: 1fr 1fr;
  }
  
  .section {
    padding: 50px 0;
  }
  
  .section-title {
    font-size: 28px;
  }
}

/* 动画效果 */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-fadeup {
  animation: fadeUp 0.6s ease forwards;
}