/* 全局样式重置 - 消除浏览器默认差异 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Microsoft YaHei", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
}
html, body {
  font-size: 16px;
  color: #333;
  background-color: #f5f7fa;
  line-height: 1.6;
  scroll-behavior: smooth; /* 平滑滚动 - 提升体验 */
}
ul, li {
  list-style: none;
}
a {
  text-decoration: none;
  color: #333;
  transition: all 0.3s ease; /* 通用过渡效果 */
}
a:hover {
  color: #0066cc; /* 主色调 - 科技蓝，适配区块链企业风格 */
}
img {
  display: block;
  max-width: 100%;
  height: auto;
  border: 0; /* 消除图片边框 */
}
/* 通用容器 - 居中布局，限制最大宽度 */
.container {
  width: 90%;
  max-width: 1200px;
  margin: 0 auto;
}
/* 通用按钮 - 重点适配TP下载按钮（SEO核心点击元素） */
.btn {
  display: inline-block;
  padding: 12px 30px;
  background-color: #0066cc;
  color: #fff !important;
  border-radius: 4px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  text-align: center;
}
.btn:hover {
  background-color: #0052aa;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 102, 204, 0.3);
}
.btn-big {
  padding: 16px 40px;
  font-size: 18px;
}
/* 通用标题样式 - SEO语义化标题层级 */
h1 {
  font-size: 36px;
  line-height: 1.3;
  margin-bottom: 20px;
}
h2 {
  font-size: 30px;
  margin-bottom: 18px;
  text-align: center;
  position: relative;
  padding-bottom: 15px;
}
h2::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 80px;
  height: 3px;
  background-color: #0066cc;
}
h3 {
  font-size: 22px;
  margin-bottom: 15px;
}
h4 {
  font-size: 18px;
  margin-bottom: 10px;
}
/* 通用段落 - 提升可读性 */
p {
  margin-bottom: 15px;
}
/* 隐藏类 - SEO友好（仅给搜索引擎看，不影响视觉） */
.seo-hide {
  position: absolute;
  left: -9999px;
  top: auto;
  width: 1px;
  height: 1px;
  overflow: hidden;
}
/* 头部导航样式 - 固定顶部，响应式折叠 */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background-color: #fff;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  z-index: 999; /* 最高层级，避免被遮挡 */
  padding: 15px 0;
}
.header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.logo {
  width: 120px;
}
.nav-list {
  display: flex;
  gap: 30px;
}
.nav-list a {
  font-size: 16px;
  font-weight: 500;
}
.nav-list a.active {
  color: #0066cc;
  font-weight: 600;
}
/* 移动端导航按钮 - 初始隐藏 */
.nav-btn {
  display: none;
  font-size: 24px;
  cursor: pointer;
}
/* 英雄区样式 - 主页核心，突出TP下载 */
.hero {
  height: 100vh;
  background: linear-gradient(135deg, #001f3f, #0066cc);
  color: #fff;
  display: flex;
  align-items: center;
  padding-top: 80px; /* 避开固定导航 */
  text-align: center;
}
.hero h1 {
  font-size: 48px;
  margin-bottom: 30px;
}
.hero p {
  font-size: 20px;
  max-width: 800px;
  margin: 0 auto 40px;
}
/* 图片新闻动态区样式 - 主页核心模块 */
.news-section {
  padding: 80px 0;
  background-color: #fff;
}
.news-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
  margin-top: 40px;
}
.news-item {
  background-color: #f9fafc;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 10px rgba(0,0,0,0.05);
  transition: all 0.3s ease;
}
.news-item:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 20px rgba(0,0,0,0.1);
}
.news-img {
  height: 200px;
  overflow: hidden;
}
.news-img img {
  width: 100%;
  height: 100%;
  object-fit: cover; /* 保持图片比例，裁剪多余部分 */
}
.news-content {
  padding: 20px;
}
.news-date {
  font-size: 14px;
  color: #999;
  margin-bottom: 10px;
}
.news-content a {
  display: inline-block;
  margin-top: 10px;
  color: #0066cc;
  font-weight: 500;
}
/* 通用模块样式 - 适配所有页面的内容区 */
.section {
  padding: 80px 0;
}
.section-white {
  background-color: #fff;
}
.section-gray {
  background-color: #f5f7fa;
}
.content {
  max-width: 1000px;
  margin: 0 auto;
  padding: 20px;
  line-height: 1.8;
}
.content img {
  margin: 20px auto;
  border-radius: 4px;
}
/* 下载页核心样式 - TP官方下载板块 */
.download-box {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 40px;
  margin-top: 60px;
  text-align: center;
}
.download-item {
  background-color: #fff;
  padding: 40px 20px;
  border-radius: 8px;
  box-shadow: 0 4px 15px rgba(0,0,0,0.08);
}
.download-item img {
  width: 80px;
  margin: 0 auto 20px;
}
/* 页脚样式 - 企业级，含SEO核心链接 */
.footer {
  background-color: #001f3f;
  color: #ccc;
  padding: 60px 0 20px;
  margin-top: 40px;
}
.footer .container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 40px;
  margin-bottom: 40px;
}
.footer-col h3 {
  color: #fff;
  font-size: 18px;
  margin-bottom: 20px;
  padding-bottom: 10px;
  border-bottom: 1px solid #333;
}
.footer-col a {
  color: #ccc;
  display: block;
  margin-bottom: 10px;
}
.footer-col a:hover {
  color: #0066cc;
  padding-left: 5px;
}
.footer-copyright {
  text-align: center;
  padding-top: 20px;
  border-top: 1px solid #333;
  font-size: 14px;
}
/* 帮助中心/联系我们 表单样式 */
.form {
  max-width: 600px;
  margin: 40px auto 0;
  background-color: #fff;
  padding: 40px;
  border-radius: 8px;
  box-shadow: 0 4px 15px rgba(0,0,0,0.08);
}
.form-item {
  margin-bottom: 20px;
}
.form-item label {
  display: block;
  margin-bottom: 8px;
  font-weight: 500;
}
.form-item input, .form-item textarea {
  width: 100%;
  padding: 12px 15px;
  border: 1px solid #ddd;
  border-radius: 4px;
  font-size: 16px;
  transition: border 0.3s ease;
}
.form-item input:focus, .form-item textarea:focus {
  outline: none;
  border-color: #0066cc;
  box-shadow: 0 0 0 2px rgba(0, 102, 204, 0.1);
}
.form-item textarea {
  height: 150px;
  resize: none;
}
/* 响应式适配 - 平板（768px以下） */
@media (max-width: 768px) {
  h1 {
    font-size: 30px;
  }
  h2 {
    font-size: 24px;
  }
  .hero h1 {
    font-size: 36px;
  }
  .hero p {
    font-size: 18px;
  }
  .nav-list {
    display: none;
    position: absolute;
    top: 70px;
    left: 0;
    width: 100%;
    background-color: #fff;
    flex-direction: column;
    padding: 20px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
  }
  .nav-list.show {
    display: flex;
  }
  .nav-btn {
    display: block;
  }
  .section {
    padding: 60px 0;
  }
  .news-section {
    padding: 60px 0;
  }
}
/* 响应式适配 - 手机（375px以下） */
@media (max-width: 375px) {
  h1 {
    font-size: 24px;
  }
  h2 {
    font-size: 20px;
  }
  .hero h1 {
    font-size: 28px;
  }
  .hero p {
    font-size: 16px;
  }
  .btn-big {
    padding: 12px 30px;
    font-size: 16px;
  }
  .form {
    padding: 20px;
  }
  .download-box {
    gap: 20px;
  }
}