/* 全局重置与基础样式 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Inter', 'Microsoft YaHei', sans-serif;
}
:root {
  --primary: #0F4C81; /* 主色：深海蓝 */
  --secondary: #2A2A2A; /* 辅助色：深灰 */
  --accent: #E6A85A; /* 点缀色：金色 */
  --light: #F8F9FA;
  --white: #FFFFFF;
  --gray: #666666;
  --border: #EEEEEE;
  --shadow: 0 5px 20px rgba(0,0,0,0.08);
  --transition: all 0.3s ease;
}
body {
  color: var(--secondary);
  line-height: 1.6;
  overflow-x: hidden;
}
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}
a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
}
ul {
  list-style: none;
}
img {
  max-width: 100%;
  height: auto;
  display: block;
}
button, .btn {
  cursor: pointer;
  border: none;
  outline: none;
  transition: var(--transition);
}
.section {
  padding: 80px 0;
}
.section-title {
  text-align: center;
  margin-bottom: 50px;
}
.section-title h2 {
  font-size: 36px;
  font-weight: 700;
  color: var(--secondary);
  margin-bottom: 15px;
  position: relative;
  display: inline-block;
}
.section-title h2::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background: var(--accent);
}
.section-title p {
  color: var(--gray);
  max-width: 700px;
  margin: 0 auto;
}
.btn-primary {
  background: var(--primary);
  color: var(--white);
  padding: 12px 30px;
  border-radius: 50px;
  font-weight: 500;
  display: inline-block;
}
.btn-primary:hover {
  background: var(--accent);
  transform: translateY(-3px);
  box-shadow: var(--shadow);
}

/* 头部导航 */
.header {
  position: sticky;
  top: 0;
  background: var(--white);
  box-shadow: var(--shadow);
  z-index: 999;
}
.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 80px;
}
.logo {
  font-size: 24px;
  font-weight: 700;
  color: var(--primary);
}
.nav-menu {
  display: flex;
  align-items: center;
}
.nav-menu > li {
  position: relative;
  margin-left: 30px;
}
.nav-menu > li > a {
  font-weight: 500;
  padding: 10px 0;
  display: block;
}
.nav-menu > li > a:hover {
  color: var(--primary);
}
/* 下拉菜单 */
.dropdown {
  position: absolute;
  top: 100%;
  left: 0;
  width: 200px;
  background: var(--white);
  box-shadow: var(--shadow);
  border-radius: 5px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: var(--transition);
}
.dropdown li {
  padding: 10px 20px;
}
.dropdown li:hover {
  background: var(--light);
  color: var(--primary);
}
.nav-menu > li:hover .dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.mobile-menu-btn {
  display: none;
  font-size: 24px;
  background: none;
}

/* Banner 通用样式 */
.banner {
  height: 400px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: var(--white);
  position: relative;
  background-size: cover;
  background-position: center;
}
.banner::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0);
}
.banner-content {
  position: relative;
  z-index: 1;
}
.banner h1 {
  font-size: 48px;
  margin-bottom: 15px;
}
.banner p {
  font-size: 18px;
  max-width: 700px;
  margin: 0 auto;
}

/* 首页Banner */
.home-banner {
  height: 600px;
  text-align: left;
}
.home-banner .container {
  width: 100%;
}
.home-banner-content {
  max-width: 600px;
}
.home-banner h1 {
  font-size: 56px;
  line-height: 1.2;
  margin-bottom: 20px;
}
.home-banner p {
  font-size: 20px;
  margin-bottom: 30px;
}

/* 产品卡片 */
.products-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}
.product-card {
  background: var(--white);
  border-radius: 10px;
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: var(--transition);
}
.product-card:hover {
  transform: translateY(-10px);
}
.product-img {
  height: 220px;
  object-fit: cover;
  width: 100%;
}
.product-info {
  padding: 20px;
}
.product-info h3 {
  font-size: 18px;
  margin-bottom: 10px;
  color: var(--secondary);
}
.product-info p {
  color: var(--gray);
  font-size: 14px;
  margin-bottom: 15px;
}

/* 服务模块 */
.services-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 25px;
  text-align: center;
}
.service-item {
  padding: 30px 20px;
  background: var(--light);
  border-radius: 10px;
  transition: var(--transition);
}
.service-item:hover {
  background: var(--primary);
  color: var(--white);
}
.service-item i {
  font-size: 40px;
  color: var(--accent);
  margin-bottom: 20px;
}
.service-item h3 {
  font-size: 18px;
  margin-bottom: 15px;
}

/* 案例模块 */
.cases-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}
.case-item {
  position: relative;
  border-radius: 10px;
  overflow: hidden;
}
.case-img {
  height: 280px;
  object-fit: cover;
  width: 100%;
}
.case-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  padding: 20px;
  background: linear-gradient(transparent, rgba(0,0,0,0.7));
  color: var(--white);
}

/* 新闻模块 */
.news-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}
.news-card {
  background: var(--white);
  border-radius: 10px;
  overflow: hidden;
  box-shadow: var(--shadow);
}
.news-img {
  height: 200px;
  object-fit: cover;
  width: 100%;
}
.news-info {
  padding: 20px;
}
.news-date {
  color: var(--accent);
  font-size: 13px;
  margin-bottom: 10px;
}
.news-info h3 {
  font-size: 18px;
  margin-bottom: 10px;
}
.news-info p {
  color: var(--gray);
  font-size: 14px;
}

/* 联系表单 */
.contact-form {
  max-width: 800px;
  margin: 0 auto;
  background: var(--white);
  padding: 40px;
  border-radius: 10px;
  box-shadow: var(--shadow);
}
.form-group {
  margin-bottom: 25px;
}
.form-group label {
  display: block;
  margin-bottom: 8px;
  font-weight: 500;
}
.form-control {
  width: 100%;
  padding: 12px 15px;
  border: 1px solid var(--border);
  border-radius: 5px;
  font-size: 15px;
  transition: var(--transition);
}
.form-control:focus {
  border-color: var(--primary);
  outline: none;
}
textarea.form-control {
  min-height: 150px;
  resize: vertical;
}

/* 分页样式 */
.pagination {
  display: flex;
  justify-content: center;
  align-items: center;
  margin-top: 50px;
  gap: 10px;
}
.page-link {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border);
  border-radius: 5px;
  transition: var(--transition);
}
.page-link:hover, .page-link.active {
  background: var(--primary);
  color: var(--white);
  border-color: var(--primary);
}
.page-prev, .page-next {
  padding: 0 20px;
}

/* 内容页上下篇 */
.article-nav {
  display: flex;
  justify-content: space-between;
  margin: 40px 0;
  padding: 20px;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.article-nav a {
  color: var(--primary);
  font-weight: 500;
}
.article-nav a:hover {
  color: var(--accent);
}

/* 内容页详情 */
.detail-content {
  padding: 40px 0;
  line-height: 1.8;
}
.detail-content h2 {
  margin: 30px 0 15px;
  color: var(--primary);
}
.detail-content p {
  margin-bottom: 15px;
  color: var(--gray);
}
.detail-img {
  margin: 30px 0;
  border-radius: 10px;
}

/* 页脚 */
.footer {
  background: var(--secondary);
  color: var(--white);
  padding: 60px 0 20px;
}
.footer-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 40px;
  margin-bottom: 40px;
}
.footer-col h3 {
  font-size: 20px;
  margin-bottom: 25px;
  position: relative;
  padding-bottom: 10px;
}
.footer-col h3::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 40px;
  height: 2px;
  background: var(--accent);
}
.footer-col ul li {
  margin-bottom: 12px;
}
.footer-col ul li a:hover {
  color: var(--accent);
}
.footer-bottom {
  text-align: center;
  padding-top: 20px;
  border-top: 1px solid rgba(255,255,255,0.1);
  color: #999;
}

/* 自适应样式 */
@media (max-width: 992px) {
  .products-grid, .cases-grid, .news-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .services-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .home-banner h1 {
    font-size: 42px;
  }
}

@media (max-width: 768px) {
  .mobile-menu-btn {
    display: block;
  }
  .nav-menu {
    position: absolute;
    top: 80px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 80px);
    background: var(--white);
    flex-direction: column;
    padding: 30px 0;
    transition: var(--transition);
  }
  .nav-menu.active {
    left: 0;
  }
  .nav-menu > li {
    margin: 10px 0;
  }
  .dropdown {
    position: static;
    opacity: 1;
    visibility: visible;
    transform: none;
    box-shadow: none;
    padding-left: 20px;
  }
  .banner h1 {
    font-size: 32px;
  }
  .home-banner {
    height: 500px;
    text-align: center;
  }
}

@media (max-width: 576px) {
  .products-grid, .cases-grid, .news-grid, .services-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .section {
    padding: 50px 0;
  }
  .section-title h2 {
    font-size: 28px;
  }
}