/* ================== 基础设置 ================== */
body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  color: #333;
  line-height: 1.6;
}

a {
  text-decoration: none;
  color: inherit;
}

img {
  max-width: 100%;
  height: auto;
}

/* 页面宽度容器 */
.container {
  width: 90%;
  max-width: 1200px;
  margin: auto;
}

/* ================== 顶部导航 ================== */
.header {
  background: #fff;
  border-bottom: 1px solid #eee;
}

.header-flex {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px 0;
}

.logo {
  height: 40px;
}

.nav a {
  margin-left: 20px;
  font-size: 15px;
}

.nav .lang {
  font-weight: bold;
}

/* ================== Banner ================== */
.banner {
  position: relative;
  width: 100%;

  /* 16:9 比例，自适应缩放的核心 */
  padding-top: 56.25%;

  background-image: url("../images/banner.jpg");
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
}


.banner-text {
  position: absolute;
  top: 50%;
  left: 10%;
  transform: translateY(-50%);
  max-width: 600px;
  color: #ffffff;
}

.banner h1 {
  font-size: 42px;
  margin-bottom: 15px;
}

.banner p {
  font-size: 18px;
  line-height: 1.6;
}

.banner-btns {
  margin-top: 20px;
}

/* ================== 按钮 ================== */
.btn {
  display: inline-block;
  background: #003366;
  color: #fff;
  padding: 12px 24px;
  margin-right: 10px;
}

.btn-outline {
  background: transparent;
  border: 2px solid #fff;
}

/* ================== 通用区块 ================== */
.section {
  padding: 60px 0;
}

.section.gray {
  background: #f7f7f7;
}

.section h2 {
  text-align: center;
  margin-bottom: 30px;
}

/* ================== 网格布局 ================== */
.grid-4 {
  display: flex;
  gap: 20px;
}

.grid-3 {
  display: flex;
  gap: 20px;
}

.card,
.product-box {
  background: #fff;
  padding: 20px;
  text-align: center;
}

.product-box img {
  height: 240px;
  object-fit: cover;
}


/* ================== CTA ================== */
.cta {
  background: #003366;
  color: #fff;
  text-align: center;
  padding: 50px 20px;
}

/* ================== 页脚 ================== */
.footer {
  background: #111;
  color: #aaa;
  text-align: center;
  padding: 20px;
}

/* ================== 产品页样式 ================== */

/* 页面标题区 */
.page-title {
  background: #f2f4f6;
  padding: 50px 0;
  text-align: center;
}

.page-title h1 {
  margin-bottom: 10px;
}

/* 产品网格 */
.product-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}

/* 单个产品卡片 */
.product-card {
  background: #fff;
  border: 1px solid #eee;
  padding: 20px;
  text-align: center;
}

/* 产品图片统一尺寸（防止乱版） */
.product-card img {
  width: 100%;
  height: 240px;
  /* 关键：固定展示高度 */
  object-fit: cover;
  /* 裁切而不是拉伸 */
  margin-bottom: 15px;
}

/* ================== About 页面布局 ================== */

/* 双栏布局 */
.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
}

/* About 图片统一控制 */
.two-col img {
  width: 100%;
  height: 320px;
  object-fit: cover;
}

/* 特性网格 */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}

.feature {
  background: #fff;
  padding: 30px;
  border: 1px solid #eee;
}

.video-box {
  position: relative;
  width: 100%;
  margin-bottom: 15px;
}

.video-cover {
  width: 100%;
  display: block;
  border-radius: 6px;
}

.play-btn {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 30px;
  background: rgba(0, 0, 0, 0.6);
  color: white;
  border: none;
  border-radius: 50%;
  width: 60px;
  height: 60px;
  cursor: pointer;
}

/* ================== Contact 信息页 ================== */

.contact-info {
  max-width: 800px;
  margin: 0 auto;
  line-height: 1.8;
}

.contact-info a {
  color: #000;
  text-decoration: none;
}

.contact-info a:hover {
  text-decoration: underline;
}

/* ================== 产品图片 ================== */

.product-detail {
  max-width: 1000px;
  margin: 1px auto;
  padding: 1px;
}

.product-main-image {
  width: 100%;
  max-width: 800px;
  height: 300px;
  margin: auto;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #f5f5f5;
}

.product-main-image img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
}

.product-thumbnails {
  display: flex;
  gap: 10px;
  margin-top: 10px;
  justify-content: center;
}

.product-thumbnails img {
  width: 80px;
  height: 80px;
  object-fit: cover;
  cursor: pointer;
  border: 2px solid transparent;
}

.product-thumbnails img:hover {
  border: 2px solid #000;
}


/* ================== 响应式（手机） ================== */
@media (max-width: 768px) {

  .grid-4,
  .grid-3 {
    flex-direction: column;
  }

  .banner {
    padding-top: 75%;
    /* 手机屏幕更高一点，更好看 */
  }

  .banner-text {
    left: 5%;
    right: 5%;
    max-width: none;
  }

  .banner-text h1 {
    font-size: 26px;
  }

  .banner-text p {
    font-size: 15px;
  }

  .product-grid {
    grid-template-columns: 1fr;
  }

  .product-card img {
    height: 200px;
  }

  .two-col {
    grid-template-columns: 1fr;
  }

  .two-col img {
    height: 220px;
  }

  .feature-grid {
    grid-template-columns: 1fr;
  }

  .product-detail {
    padding: 15px;
    margin: 30px auto;
  }

  .product-main-image {
    height: 300px;
  }

  .product-thumbnails {
    flex-wrap: wrap;
    justify-content: center;
  }

  .product-thumbnails img {
    width: 60px;
    height: 60px;
  }

  .product-info h2 {
    font-size: 22px;
  }
}