/* 瀑布流容器 - 使用绝对定位实现真正的瀑布流（水平优先，短列优先） */
.waterfall-grid {
  position: relative;
  width: 100%;
}

/* 瀑布流卡片 - 绝对定位，由 JS 计算位置 */
.waterfall-item {
  position: absolute;
  opacity: 0;
  /* 初始状态：只有 opacity 动画，没有 transform 动画，避免"发牌"效果 */
  transition: opacity 0.4s ease;
}

/* 卡片就绪状态（位置计算完成后添加） */
.waterfall-item.ready {
  opacity: 1;
  /* 就绪后才启用 transform 动画，用于窗口 resize 时的平滑重排 */
  transition: transform 0.3s ease, opacity 0.4s ease;
}

/* 瀑布流卡片 */
.waterfall-card {
  position: relative;
  display: flex;
  flex-direction: column;
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.waterfall-card:hover {
  transform: translateY(-4px);
}

/* 封面图容器 - 使用 aspect-ratio 预设占位高度，避免重排 */
.waterfall-cover {
  position: relative;
  display: block;
  width: 100%;
  overflow: hidden;
  border-radius: 0.75rem;
  background-color: var(--bg-tertiary);
}

/* 骨架屏层 */
.skeleton-layer {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(
    90deg,
    var(--bg-tertiary) 0%,
    var(--bg-secondary) 50%,
    var(--bg-tertiary) 100%
  );
  background-size: 200% 100%;
  animation: skeleton-pulse 1.5s ease-in-out infinite;
  border-radius: 0.75rem;
  z-index: 2;
  opacity: 1;
  transition: opacity 0.3s ease;
}

/* 图片加载完成后隐藏骨架屏 */
.waterfall-cover.loaded .skeleton-layer {
  opacity: 0;
  pointer-events: none;
}

@keyframes skeleton-pulse {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* 封面图片默认透明，加载完成后显示 */
.waterfall-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 0.5s ease, opacity 0.3s ease;
  opacity: 0;
}

.waterfall-cover.loaded img {
  opacity: 1;
}

.waterfall-card:hover .waterfall-cover img {
  transform: scale(1.05);
}

.waterfall-card:hover .waterfall-cover {
  box-shadow: var(--shadow-hover);
}

/* 信息区域骨架屏 */
.skeleton-info {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
  opacity: 1;
  transition: opacity 0.3s ease;
}

.waterfall-info.loaded .skeleton-info {
  opacity: 0;
  pointer-events: none;
}

.skeleton-title {
  height: 14px;
  background: linear-gradient(
    90deg,
    var(--bg-tertiary) 0%,
    var(--bg-secondary) 50%,
    var(--bg-tertiary) 100%
  );
  background-size: 200% 100%;
  animation: skeleton-pulse 1.5s ease-in-out infinite;
  border-radius: 4px;
  margin-bottom: 8px;
  width: 80%;
}

.skeleton-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.skeleton-avatar {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: linear-gradient(
    90deg,
    var(--bg-tertiary) 0%,
    var(--bg-secondary) 50%,
    var(--bg-tertiary) 100%
  );
  background-size: 200% 100%;
  animation: skeleton-pulse 1.5s ease-in-out infinite;
}

.skeleton-name {
  height: 12px;
  width: 60px;
  margin-left: 6px;
  background: linear-gradient(
    90deg,
    var(--bg-tertiary) 0%,
    var(--bg-secondary) 50%,
    var(--bg-tertiary) 100%
  );
  background-size: 200% 100%;
  animation: skeleton-pulse 1.5s ease-in-out infinite;
  border-radius: 4px;
}

/* 信息区域真实内容默认隐藏 */
.waterfall-info .real-content {
  opacity: 0;
  transition: opacity 0.3s ease;
}

.waterfall-info.loaded .real-content {
  opacity: 1;
}

/* 媒体标签 */
.waterfall-badges {
  position: absolute;
  top: 8px;
  right: 8px;
  display: flex;
  gap: 4px;
}

/* 信息区域 */
.waterfall-info {
  position: relative;
  padding: 0.5rem 0 0;
  text-align: left;
  min-height: 52px;
}

.waterfall-title {
  font-size: 0.8125rem;
  font-weight: 500;
  margin: 0 0 0.25rem 0;
  line-height: 1.4;
  color: var(--color-primary);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.waterfall-title a {
  color: inherit;
  text-decoration: none;
}

.waterfall-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
}

/* 分类信息 */
.waterfall-category {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  min-width: 0;
  flex: 1;
  text-decoration: none;
}

.waterfall-category:hover .waterfall-category-name {
  color: var(--color-primary);
}

.waterfall-category-avatar {
  width: 1.25rem;
  height: 1.25rem;
  border-radius: 50%;
  overflow: hidden;
  flex-shrink: 0;
  background-color: var(--bg-tertiary);
}

.waterfall-category-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.waterfall-category-name {
  font-size: 0.75rem;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: color 0.2s ease;
}

/* 收藏按钮 */
.waterfall-favorite {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  padding: 0;
  border: none;
  background: transparent;
  color: var(--text-muted);
  font-size: 0.75rem;
  cursor: pointer;
  transition: color 0.2s ease;
  flex-shrink: 0;
}

.waterfall-favorite:hover {
  color: #ec4899;
}

.waterfall-favorite.is-favorited {
  color: #ec4899;
}

.waterfall-favorite svg {
  transition: transform 0.2s ease;
}

.waterfall-favorite:hover svg {
  transform: scale(1.15);
}

/* 加载状态 */
.waterfall-loading {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 40px;
  color: var(--text-muted);
}

.waterfall-spinner {
  width: 24px;
  height: 24px;
  border: 3px solid var(--bg-tertiary);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin-right: 12px;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* 触底哨兵 */
.scroll-sentinel {
  height: 1px;
  width: 100%;
}

/* 隐藏滚动条但保持可滚动 */
.scrollbar-hide {
  -ms-overflow-style: none;
  scrollbar-width: none;
}
.scrollbar-hide::-webkit-scrollbar {
  display: none;
}