/* 全局重置+基础样式 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "微软雅黑", "PingFang SC", sans-serif;
}
body {
  background-color: #ffffff;
  color: #333333;
  line-height: 1.8;
}

/* 导航栏（精致黑+淡蓝高亮） */
.navbar {
  background-color: #1f2937;
  color: #ffffff;
  padding: 18px 5%;
  position: sticky;
  top: 0;
  z-index: 999;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}
.navbar .logo {
  font-size: 24px;
  font-weight: 700;
  letter-spacing: 1px;
}
.navbar .menu {
  display: flex;
  gap: 30px;
}
.navbar .menu a {
  color: #e5e7eb;
  text-decoration: none;
  font-size: 16px;
  transition: all 0.3s;
  padding: 4px 0;
  border-bottom: 2px solid transparent;
}
.navbar .menu a:hover {
  color: #3b82f6;
  border-bottom: 2px solid #3b82f6;
}

/* Banner区（渐变+大图+层次感） */
.banner {
  background: linear-gradient(135deg, #1f2937 0%, #374151 100%);
  color: #ffffff;
  padding: 100px 5%;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.banner::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: url("../img/banner-bg.png") no-repeat center;
  background-size: cover;
  opacity: 0.1;
}

/* ========== 核心修改1：统一标题和小字的基础样式 ========== */
/* Banner区标题样式（补充行高，和小字统一） */
.banner h1 {
  font-size: 42px;
  margin-bottom: 20px;
  position: relative;
  font-weight: 700;
  line-height: 1.2; /* 新增：和小字行高一致 */
}

/* Banner区小字样式（修正错误+提高优先级） */
.banner p.banner-sub { /* 修改：用p.banner-sub提高优先级，避免被通用p样式覆盖 */
  font-size: 42px; /* 和标题字号一致 */
  font-weight: 700; /* 和标题加粗一致 */
  color: #ffffff; /* 修正：#ffff是错误值，改为标准#ffffff */
  text-align: center; /* 和标题对齐一致 */
  line-height: 1.2; /* 和标题行高一致 */
  margin-top: 10px;
  position: relative; /* 新增：和标题一样相对定位，避免被遮罩层覆盖 */
}

/* Banner区其他p标签样式（移到banner-sub之后，避免覆盖） */
.banner p {
  font-size: 18px;
  color: #e5e7eb;
  max-width: 800px;
  margin: 0 auto;
  position: relative;
}

/* 新增：Banner最下面小字强制下移样式 */
.banner .banner-bottom-text {
  margin-top: 40px !important; /* 调整数值可控制下移幅度（比如50px） */
}
/* 通用模块标题样式 */
.section-title {
  font-size: 32px;
  color: #1f2937;
  text-align: center;
  margin-bottom: 40px;
  position: relative;
}
.section-title::after {
  content: "";
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background-color: #3b82f6;
}

/* 关于我们模块（增加留白+段落间距） */
.about {
  padding: 80px 5%;
  max-width: 1200px;
  margin: 0 auto;
}
.about p {
  font-size: 16px;
  color: #4b5563;
  line-height: 2;
  margin-bottom: 20px;
  text-align: left;
}

/* 产品中心（精致卡片+ hover动效） */
.products {
  padding: 80px 5%;
  background-color: #f9fafb;
}
.product-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
  max-width: 1200px;
  margin: 0 auto;
}
.product-item {
  background-color: #ffffff;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 4px 20px rgba(0,0,0,0.05);
  transition: transform 0.3s, box-shadow 0.3s;
}
.product-item:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 30px rgba(0,0,0,0.1);
}
.product-item img {
  width: 100%;
  height: 220px;
  object-fit: contain;
  padding: 20px;
  background-color: #f9fafb;
}
.product-info {
  padding: 24px;
}
.product-info h3 {
  font-size: 20px;
  color: #1f2937;
  margin-bottom: 12px;
}
.product-info p {
  font-size: 14px;
  color: #6b7280;
  line-height: 1.7;
}

/* 联系我们（简洁卡片） */
.contact {
  padding: 80px 5%;
  max-width: 1200px;
  margin: 0 auto;
}
.contact-card {
  background-color: #ffffff;
  padding: 30px;
  border-radius: 12px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.05);
  text-align: left;
  max-width: 600px;
  margin: 0 auto;
}
.contact-card p {
  font-size: 16px;
  color: #4b5563;
  margin-bottom: 10px;
}
.contact-card p span {
  color: #3b82f6;
  font-weight: 500;
}

/* 页脚（深灰+简洁） */
.footer {
  background-color: #1f2937;
  color: #e5e7eb;
  text-align: center;
  padding: 30px 5%;
  font-size: 14px;
  margin-top: 40px;
}

/* ========== 核心修改2：手机端适配同步 ========== */
@media (max-width: 768px) {
  .navbar {
    flex-direction: column;
    gap: 15px;
  }
  .banner h1 {
    font-size: 30px;
  }
  /* 新增：手机端小字和标题字号同步 */
  .banner p.banner-sub {
    font-size: 30px;
  }
  .section-title {
    font-size: 26px;
  }
  .product-list {
    grid-template-columns: 1fr;
  }
}