/* 移动端封面图样式 */
@media screen and (max-width: 768px) {
  /* 首页头部封面 */
  body section header.cover,
  body > header.cover,
  header.cover.bg-top,
  header.cover.bg-center,
  header.cover {
    background-image: url('/images/blog-cover.jpg') !important;
    background-size: cover !important;
    background-position: -20px top !important;
  }
  
  /* 文章页面头部封面 */
  article header.cover {
    background-image: url('/images/blog-cover.jpg') !important;
    background-size: cover !important;
    background-position: -20px top !important;
  }
}

/* 移动端底部留白优化 */
@media screen and (max-width: 768px) {
  body > main {
    padding-bottom: 1rem !important;
  }
}

/* 视频 iframe 响应式自适应 */
iframe {
  width: 100%;
  max-width: 800px;
  height: auto;
  aspect-ratio: 16 / 9;
}

/* mermaid 图表居中 */
.mermaid {
  display: block;
  margin-left: auto;
  margin-right: auto;
}