/* 全局样式 */
:root {
  --primary-color: #2563eb;
  --secondary-color: #1e40af;
  --text-color: #1f2937;
  --light-bg: #f9fafb;
  --container-width: 1200px;
  --section-spacing: 6rem;
  --border-radius: 1rem;
}

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

/* 容器样式 */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 2rem;
  width: 100%;
}

/* 导航栏样式 */
.nav {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  padding: 1.25rem 0;
  position: fixed;
  width: 100%;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.nav-links a {
  transition: opacity 0.2s;
}

.nav-links a:hover {
  opacity: 0.8;
}

/* Banner样式 */
.banner {
  background: linear-gradient(135deg, #1e3a8a 0%, #3b82f6 100%);
  color: white;
  padding: 10rem 0 6rem;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.banner::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><rect fill="rgba(255,255,255,0.03)" x="0" y="0" width="100" height="100"/></svg>') repeat;
  opacity: 0.5;
}

.banner .container {
  max-width: 900px;
  position: relative;
}

/* 按钮样式 */
.btn {
  display: inline-block;
  padding: 1rem 2rem;
  border-radius: 0.5rem;
  font-weight: 600;
  text-align: center;
  transition: all 0.3s;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  box-shadow: 0 4px 15px rgba(37,99,235,0.2);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(37,99,235,0.3);
}

/* 区块样式 */
.section {
  padding: var(--section-spacing) 0;
  margin: 0 auto;
  background-color: white;
  position: relative;
}

.section:nth-child(even) {
  background-color: var(--light-bg);
}

.section h2 {
  position: relative;
  padding-bottom: 1rem;
  margin-bottom: 3rem;
}

.section h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 60px;
  height: 4px;
  background: linear-gradient(to right, var(--primary-color), var(--secondary-color));
  border-radius: 2px;
}

/* 卡片样式 */
.card {
  background: white;
  border-radius: var(--border-radius);
  box-shadow: 0 4px 20px rgba(0,0,0,0.05);
  padding: 2rem;
  transition: transform 0.3s, box-shadow 0.3s;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 30px rgba(0,0,0,0.1);
}

/* 表格样式 */
.table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  margin: 2rem 0;
  background-color: white;
  border-radius: var(--border-radius);
  overflow: hidden;
  box-shadow: 0 4px 20px rgba(0,0,0,0.05);
}

.table th {
  background: var(--light-bg);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  padding: 1.25rem;
  border-bottom: 2px solid #e5e7eb;
}

.table td {
  padding: 1.25rem;
  border-bottom: 1px solid #e5e7eb;
}

.table tr:last-child td {
  border-bottom: none;
}

/* 快捷导航样式 */
.quick-nav {
  position: fixed;
  left: 2rem;
  top: 50%;
  transform: translateY(-50%);
  background: white;
  padding: 1.5rem;
  border-radius: var(--border-radius);
  box-shadow: 0 4px 20px rgba(0,0,0,0.1);
  z-index: 90;
}

.quick-nav a {
  display: block;
  padding: 0.5rem 1rem;
  color: var(--text-color);
  transition: all 0.2s;
  border-radius: 0.375rem;
}

.quick-nav a:hover {
  background: var(--light-bg);
  color: var(--primary-color);
}

.quick-nav a.active {
  background: var(--primary-color);
  color: white;
}

/* 移动端隐藏快捷导航 */
@media (max-width: 768px) {
  .quick-nav {
    display: none;
  }
  
  .container {
    padding: 0 1rem;
  }
  
  .section {
    padding: 4rem 0;
  }
  
  .banner {
    padding: 8rem 0 4rem;
  }
}

/* 页脚样式 */
.footer {
  background: linear-gradient(135deg, #1f2937, #111827);
  color: white;
  padding: 6rem 0 4rem;
  text-align: center;
  position: relative;
}

.footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(to right, var(--primary-color), var(--secondary-color));
}

.footer h3 {
  color: #f3f4f6;
  margin-bottom: 1.5rem;
  font-size: 1.25rem;
}

.footer p {
  color: #9ca3af;
}

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

.section {
  animation: fadeInUp 0.6s ease-out;
}