/* 基础重置 */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: "Noto Serif SC", "Source Han Serif SC", "SimSun", Georgia, serif;
  line-height: 1.8;
  color: #222;
  background: #fafafa;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}
.container { max-width: 960px; margin: 0 auto; padding: 0 20px; }

/* 主内容区自动伸缩，确保 footer 在底部 */
main.container {
  flex: 1;
}

/* 头部 */
.site-header {
  background: #0b2b4f;
  color: #fff;
  padding: 16px 0;
  border-bottom: 4px solid #c00;
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
}

/* ===== 统一 Logo 样式（所有页面高度 50px）===== */
.site-logo {
  height: 50px;
  width: auto;
  vertical-align: middle;
}

.main-nav a {
  color: #fff;
  text-decoration: none;
  margin-left: 24px;
  font-size: 16px;
  font-weight: 500;
}
.main-nav a:hover { text-decoration: underline; }

/* 首页介绍 */
.home-intro {
  text-align: center;
  padding: 40px 0 20px;
  border-bottom: 2px solid #ddd;
  margin-bottom: 30px;
}
.home-intro h1 { font-size: 2.5rem; color: #0b2b4f; }
.home-intro p { font-size: 1.2rem; color: #666; }

/* 文章卡片 */
.article-card {
  background: #fff;
  padding: 24px;
  margin-bottom: 20px;
  border-radius: 4px;
  box-shadow: 0 1px 4px rgba(0,0,0,0.1);
}
.article-card h2 { font-size: 1.8rem; margin-bottom: 8px; }
.article-card h2 a { color: #0b2b4f; text-decoration: none; }
.article-card h2 a:hover { text-decoration: underline; }
.article-card .meta {
  font-size: 0.9rem;
  color: #888;
  margin-bottom: 12px;
}
.article-card .category {
  background: #c00;
  color: #fff;
  padding: 2px 8px;
  border-radius: 2px;
  font-size: 0.8rem;
  margin-left: 10px;
}

/* 文章详情页（优化阅读宽度） */
.article-full {
  background: #fff;
  padding: 30px 35px;
  margin: 30px auto;
  box-shadow: 0 1px 4px rgba(0,0,0,0.1);
  max-width: 860px;
  border-radius: 2px;
}
.article-full h1 {
  font-size: 2.2rem;
  color: #0b2b4f;
  margin-bottom: 10px;
}
.article-full .content {
  margin-top: 30px;
  font-size: 1.05rem;
}
.article-full .content p { margin-bottom: 1.2em; }
.article-full .content h2,
.article-full .content h3 { margin: 1.5em 0 0.5em; }

/* 页脚（自动贴底） */
.site-footer {
  background: #0b2b4f;
  color: #ccc;
  text-align: center;
  padding: 24px;
  margin-top: 40px;
  font-size: 0.9rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
  .site-header .container {
    flex-direction: column;
    align-items: flex-start;
  }
  .main-nav {
    margin-top: 10px;
  }
  .main-nav a {
    margin-left: 0;
    margin-right: 16px;
  }
  .home-intro h1 {
    font-size: 2rem;
  }
  .article-card h2 {
    font-size: 1.4rem;
  }

  /* 移动端文章详情减少内边距，充分利用屏幕 */
  .article-full {
    padding: 20px 18px;
    margin: 20px 10px;
    max-width: 100%;
  }
  .article-full h1 {
    font-size: 1.8rem;
  }
  .article-full .content {
    font-size: 1rem;
  }
}

@media (min-width: 769px) and (max-width: 1024px) {
  .article-full {
    max-width: 90%;
    padding: 25px 30px;
  }
}