/* 视频卡片样式 */
.video-card {
  background: #fff;
  padding: 20px;
  border-radius: 8px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.08);
  transition: transform 0.2s, box-shadow 0.2s;
  position: relative;
}

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

.video-card h3 {
  margin: 0 0 10px 0;
  font-size: 17px;
}

.video-card .meta {
  color: #666;
  font-size: 13px;
  margin: 0 0 8px 0;
}

.video-card .oneline {
  color: #888;
  font-size: 14px;
  line-height: 1.5;
  margin: 0;
}

.video-card .ranking {
  position: absolute;
  top: 10px;
  right: 10px;
  background: #ff6b6b;
  color: #fff;
  padding: 4px 10px;
  border-radius: 4px;
  font-size: 12px;
  font-weight: bold;
}

.video-card .date {
  display: inline-block;
  margin-top: 10px;
  color: #0066cc;
  font-size: 13px;
}

/* 响应式 */
@media (max-width: 768px) {
  .video-grid {
    grid-template-columns: 1fr !important;
  }

  .container {
    padding: 0 10px;
  }

  main.container {
    padding: 20px 10px !important;
  }

  article {
    padding: 25px 20px !important;
  }
}

/* 返回顶部按钮 */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: #0066cc;
  color: #fff;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  display: none;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: 0 2px 10px rgba(0,0,0,0.2);
  transition: background 0.3s;
  z-index: 999;
}

.back-to-top:hover {
  background: #0052a3;
}

.back-to-top.show {
  display: flex;
}