/* 全局重置与基础样式 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Microsoft YaHei", Arial, sans-serif;
}

body {
  color: #333;
  line-height: 1.6;
  background-color: #fff;
}

a {
  text-decoration: none;
  color: #333;
}

ul {
  list-style: none;
}

.container {
  width: 90%;
  max-width: 1200px;
  margin: 0 auto;
}

/* 图片通用样式 */
img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 8px;
  object-fit: cover;
}

/* 导航栏 */
.header {
  background: #fff;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
  position: sticky;
  top: 0;
  z-index: 999;
}

.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 80px;
}

.logo {
  font-size: 22px;
  font-weight: bold;
  color: #165DFF;
}

.nav-menu {
  display: flex;
  gap: 40px;
}

.nav-menu a {
  font-size: 16px;
  padding: 10px 0;
  transition: 0.3s;
}

.nav-menu a:hover,
.nav-menu a.active {
  color: #165DFF;
  border-bottom: 2px solid #165DFF;
}

/* Banner 通用 */
.banner {
  height: 400px;
  background: linear-gradient(rgba(22,93,255,0.8), rgba(22,93,255,0.9)), url('https://picsum.photos/id/1048/1920/1080');
  background-size: cover;
  background-position: center;
  color: #fff;
  display: flex;
  align-items: center;
  text-align: center;
}

.banner h1 {
  font-size: 42px;
  margin-bottom: 20px;
}

.banner p {
  font-size: 18px;
  max-width: 700px;
  margin: 0 auto;
}

/* 内容区块 */
.section {
  padding: 60px 0;
}

.section-title {
  text-align: center;
  font-size: 32px;
  margin-bottom: 40px;
  color: #222;
  position: relative;
}

.section-title::after {
  content: '';
  width: 60px;
  height: 3px;
  background: #165DFF;
  display: block;
  margin: 10px auto;
}

/* 卡片布局（带图片） */
.card-box {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 30px;
  margin-top: 30px;
}

.card {
  padding: 0;
  background: #f8f9fa;
  border-radius: 8px;
  text-align: center;
  transition: 0.3s;
  overflow: hidden;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.card-img {
  height: 180px;
}

.card-body {
  padding: 25px;
}

.card h3 {
  color: #165DFF;
  margin-bottom: 15px;
  font-size: 20px;
}

/* 首页大图模块 */
.home-banner {
  padding: 0 0 60px;
}
.home-img {
  border-radius: 12px;
  box-shadow: 0 8px 20px rgba(0,0,0,0.1);
}

/* 按钮 */
.btn {
  display: inline-block;
  padding: 12px 30px;
  background: #165DFF;
  color: #fff;
  border-radius: 4px;
  margin-top: 20px;
  transition: 0.3s;
}

.btn:hover {
  background: #0b4bdf;
}

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

.form-group {
  margin-bottom: 20px;
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 15px;
  border: 1px solid #ddd;
  border-radius: 4px;
  font-size: 16px;
}

.form-group textarea {
  min-height: 150px;
  resize: vertical;
}

/* 联系信息 */
.contact-info {
  text-align: center;
  margin-bottom: 40px;
  font-size: 16px;
  line-height: 2.5;
}

/* 页脚 */
.footer {
  background: #222;
  color: #fff;
  padding: 40px 0;
  text-align: center;
}

.footer p {
  margin-bottom: 10px;
}

/* 响应式 */
@media (max-width: 768px) {
  .nav {
    flex-direction: column;
    height: auto;
    padding: 20px 0;
  }
  .nav-menu {
    margin-top: 20px;
    gap: 20px;
  }
  .banner {
    height: 300px;
    padding: 0 20px;
  }
  .banner h1 {
    font-size: 28px;
  }
  .card-img {
    height: 150px;
  }
}