/* 
 * 全局样式文件
 * 色彩方案：科技蓝(#2A5CAA), 活力橙(#FF6B35), 中性灰(#F5F7FA), 深灰(#333333)
 * 字体：思源黑体, Inter
 */

:root {
  --primary-blue: #2A5CAA;
  --primary-orange: #FF6B35;
  --neutral-gray: #F5F7FA;
  --dark-gray: #333333;
  --text-color: #333333;
  --white: #ffffff;
  --font-main: 'Inter', 'Source Han Sans CN', 'Noto Sans SC', system-ui, -apple-system, sans-serif;
  --transition-speed: 0.3s;
}

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

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

body {
  font-family: var(--font-main);
  color: var(--text-color);
  background-color: var(--neutral-gray);
  line-height: 1.6;
  overflow-x: hidden;
  opacity: 0;
  animation: fadeIn 0.8s ease-out forwards;
}

/* 布局容器 */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* 导航栏 */
header {
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

nav {
  display: flex;
  justify-content: center; /* 居中显示 */
  align-items: center;
  height: 70px;
}

nav ul {
  display: flex;
  list-style: none;
  gap: 40px;
}

nav a {
  text-decoration: none;
  color: var(--dark-gray);
  font-weight: 500;
  font-size: 1.1rem;
  transition: color var(--transition-speed);
  position: relative;
}

nav a::after {
  content: '';
  position: absolute;
  width: 0;
  height: 2px;
  bottom: -4px;
  left: 0;
  background-color: var(--primary-blue);
  transition: width var(--transition-speed);
}

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

nav a:hover::after {
  width: 100%;
}

/* Hero 区域 */
.hero {
  position: relative;
  height: 80vh;
  min-height: 500px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--white);
  text-align: center;
  overflow: hidden;
  background-size: cover;
  background-position: center;
  background-attachment: fixed; /* 视差效果 */
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(42,92,170,0.8), rgba(255,107,53,0.3));
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 800px;
  padding: 20px;
  transform: translateY(20px);
  animation: slideUp 0.8s ease-out 0.2s forwards;
  opacity: 0;
}

.hero h1 {
  font-size: 3.5rem;
  font-weight: 700;
  margin-bottom: 1rem;
  letter-spacing: 2px;
}

.hero p {
  font-size: 1.5rem;
  opacity: 0.9;
}

/* 通用区块 */
section {
  padding: 80px 0;
}

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

.section-title h2 {
  font-size: 2.5rem;
  color: var(--primary-blue);
  margin-bottom: 15px;
}

.section-title p {
  color: #666;
  max-width: 600px;
  margin: 0 auto;
}

/* 网格布局 */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
}

/* 卡片样式 */
.card {
  background: var(--white);
  border-radius: 12px;
  padding: 40px 30px;
  text-align: center;
  box-shadow: 0 4px 20px rgba(0,0,0,0.05);
  transition: transform var(--transition-speed), box-shadow var(--transition-speed);
  display: flex;
  flex-direction: column;
  align-items: center;
}

.card:hover {
  transform: translateY(-10px);
  box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.card-icon {
  width: 80px;
  height: 80px;
  margin-bottom: 25px;
  object-fit: contain;
}

.card h3 {
  font-size: 1.5rem;
  margin-bottom: 15px;
  color: var(--dark-gray);
}

.card p {
  color: #666;
  font-size: 1rem;
  line-height: 1.7;
}

/* 价值主张 / 理念部分 */
.split-section {
  display: flex;
  align-items: center;
  gap: 60px;
  padding: 60px 0;
}

.split-content {
  flex: 1;
}

.split-image {
  flex: 1;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.split-image img {
  width: 100%;
  height: auto;
  display: block;
  transition: transform 0.5s ease;
}

.split-image:hover img {
  transform: scale(1.05);
}

/* 列表样式 */
.feature-list {
  list-style: none;
  margin-top: 30px;
}

.feature-list li {
  margin-bottom: 15px;
  padding-left: 25px;
  position: relative;
  font-weight: 500;
}

.feature-list li::before {
  content: '✓';
  color: var(--primary-orange);
  position: absolute;
  left: 0;
  font-weight: bold;
}

/* 页脚 */
footer {
  background-color: var(--dark-gray);
  color: #999;
  text-align: center;
  padding: 30px 0;
  margin-top: auto;
}

footer p {
  font-size: 0.9rem;
  letter-spacing: 1px;
}

/* 动画定义 */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* 响应式适配 */
@media (max-width: 768px) {
  .hero h1 {
    font-size: 2.5rem;
  }
  
  .hero p {
    font-size: 1.1rem;
  }

  nav ul {
    gap: 20px;
  }
  
  nav a {
    font-size: 1rem;
  }

  .split-section {
    flex-direction: column;
    text-align: center;
  }
  
  .feature-list li {
    display: inline-block;
    margin-right: 15px;
  }

  .section-title h2 {
    font-size: 2rem;
  }
}