/* ============================================
   我的中国足迹 v4.0 — Collection Page Styles
   旅行相册：Pinterest 瀑布流 + 筛选标签 + 全屏预览
   ============================================ */

/* === Page Container === */
.collection-page {
  padding: var(--space-xl);
  margin: 0 auto;
  animation: fadeIn var(--transition-normal);
  max-width: 1200px;
}

/* ============================================
   Hero Stats Bar — 4 卡片
   ============================================ */
.collection-hero {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-base);
  margin-bottom: var(--space-xl);
}

.collection-hero__card {
  background: var(--color-glass-bg);
  backdrop-filter: var(--glass-blur-light);
  -webkit-backdrop-filter: var(--glass-blur-light);
  border: var(--glass-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg) var(--space-base);
  text-align: center;
  box-shadow: var(--glass-shadow);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
  cursor: default;
}
.collection-hero__card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.collection-hero__number {
  font-size: var(--font-display-xl);
  font-weight: var(--weight-bold);
  color: var(--color-primary);
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.collection-hero__label {
  font-size: var(--font-caption-sm);
  color: var(--color-muted);
  margin-top: var(--space-xs);
  font-weight: var(--weight-medium);
}

/* ============================================
   Filter Bar — 筛选标签栏
   ============================================ */
.collection-filter-bar {
  display: flex;
  align-items: flex-start;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
  flex-wrap: wrap;
}

/* Pill 按钮容器：横向滚动 */
.collection-pills {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  flex: 1;
  min-width: 0;
}

/* 单个 Pill */
.collection-pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 36px;
  padding: 0 16px;
  font-size: var(--font-caption-sm);
  font-weight: var(--weight-medium);
  color: var(--color-body);
  background: var(--color-surface-soft);
  border: 1px solid transparent;
  border-radius: var(--radius-full);
  cursor: pointer;
  white-space: nowrap;
  transition: all var(--transition-fast);
  user-select: none;
  font-family: inherit;
  line-height: 1;
}
.collection-pill:hover {
  background: var(--color-primary-light);
  color: var(--color-primary);
}
.collection-pill--active {
  background: var(--color-primary);
  color: var(--color-on-primary);
  border-color: var(--color-primary);
}
.collection-pill--active:hover {
  background: var(--color-primary-hover);
  color: var(--color-on-primary);
}

/* 分组切换按钮 */
.collection-group-toggle {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: 36px;
  padding: 0 16px;
  font-size: var(--font-caption-sm);
  font-weight: var(--weight-medium);
  color: var(--color-body);
  background: var(--color-surface-soft);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-full);
  cursor: pointer;
  white-space: nowrap;
  transition: all var(--transition-fast);
  user-select: none;
  font-family: inherit;
  flex-shrink: 0;
}
.collection-group-toggle:hover {
  background: var(--color-primary-light);
  color: var(--color-primary);
  border-color: var(--color-primary);
}
.collection-group-toggle--active {
  background: var(--color-primary);
  color: var(--color-on-primary);
  border-color: var(--color-primary);
}
.collection-group-toggle--active:hover {
  background: var(--color-primary-hover);
  color: var(--color-on-primary);
}

/* ============================================
   Content Area
   ============================================ */
.collection-content {
  min-height: 200px;
}

/* ============================================
   CSS Columns 瀑布流照片墙
   ============================================ */
.collection-photo-wall {
  column-count: 4;
  column-gap: var(--space-base);
}

/* ============================================
   Photo Card — 大圆角 + hover 放大发光
   ============================================ */
.photo-card {
  break-inside: avoid;
  margin-bottom: var(--space-base);
  border-radius: var(--radius-lg);
  overflow: hidden;
  cursor: pointer;
  position: relative;
  background: var(--color-surface-soft);
  transition: transform 0.35s cubic-bezier(0.25, 0.1, 0.25, 1),
              box-shadow 0.35s cubic-bezier(0.25, 0.1, 0.25, 1);
  animation: fadeInUp 0.45s ease both;
}
.photo-card:hover {
  transform: scale(1.03);
  box-shadow:
    0 8px 32px rgba(255, 111, 174, 0.28),
    0 2px 8px rgba(0, 0, 0, 0.08);
  z-index: 1;
}

/* 图片本身 */
.photo-card img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
}

/* 占位符（无照片时） */
.photo-card__placeholder {
  width: 100%;
  aspect-ratio: 4 / 3;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 48px;
  color: var(--color-muted-soft);
  background: var(--color-surface-soft);
}

/* ---- 叠加层：城市名 + 日期 ---- */
.photo-card__overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 28px 14px 12px;
  background: linear-gradient(
    to top,
    rgba(0, 0, 0, 0.55) 0%,
    rgba(0, 0, 0, 0.15) 60%,
    transparent 100%
  );
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 8px;
  pointer-events: none;
}

.photo-card__city {
  font-size: var(--font-caption-sm);
  font-weight: var(--weight-semibold);
  color: #fff;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
  line-height: 1.2;
  max-width: 65%;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.photo-card__date {
  font-size: 11px;
  font-weight: var(--weight-medium);
  color: rgba(255, 255, 255, 0.85);
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
  white-space: nowrap;
  flex-shrink: 0;
}

/* ============================================
   按省份分组模式
   ============================================ */
.collection-province-section {
  margin-bottom: var(--space-xl);
}

.collection-province-header {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-base);
  padding-bottom: var(--space-sm);
  border-bottom: 1px solid var(--color-hairline-soft);
}

.collection-province-name {
  font-size: var(--font-display-sm);
  font-weight: var(--weight-semibold);
  color: var(--color-ink);
  cursor: pointer;
  transition: color var(--transition-fast);
  flex-shrink: 0;
}
.collection-province-name:hover {
  color: var(--color-primary);
}

.collection-province-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
}

.collection-city-tag {
  font-size: var(--font-caption-sm);
  padding: 3px 12px;
  border-radius: var(--radius-full);
  background: var(--color-primary-light);
  color: var(--color-primary);
  font-weight: var(--weight-medium);
}

/* ============================================
   空照片提示
   ============================================ */
.collection-no-photos {
  text-align: center;
  padding: var(--space-xxl) var(--space-lg);
  font-size: var(--font-body-md);
  color: var(--color-muted-soft);
  column-span: all;
}

/* ============================================
   全屏照片查看器 (Modal 内)
   ============================================ */
.photo-viewer {
  text-align: center;
}
.photo-viewer img {
  max-width: 100%;
  max-height: 65vh;
  border-radius: var(--radius-md);
  object-fit: contain;
}
.photo-viewer__info {
  margin-top: var(--space-base);
  font-size: var(--font-body-sm);
  color: var(--color-muted);
  line-height: 1.6;
}
.photo-viewer__info strong {
  color: var(--color-ink);
}
.photo-viewer__note {
  font-size: 13px;
  color: var(--color-muted);
}

/* ============================================
   空状态
   ============================================ */
.collection-empty {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--space-section) var(--space-lg);
  text-align: center;
}
.collection-empty__icon {
  font-size: 56px;
  margin-bottom: var(--space-lg);
}
.collection-empty__title {
  font-size: var(--font-display-sm);
  font-weight: var(--weight-semibold);
  color: var(--color-ink);
  margin-bottom: var(--space-sm);
}
.collection-empty__text {
  font-size: var(--font-body-md);
  color: var(--color-muted);
  margin-bottom: var(--space-lg);
}

/* ============================================
   响应式
   ============================================ */

/* 中等屏幕：3 列瀑布流 */
@media (max-width: 980px) {
  .collection-photo-wall {
    column-count: 3;
  }
  .collection-hero {
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-sm);
  }
  .collection-hero__number {
    font-size: var(--font-display-lg);
  }
}

/* 平板：2 列瀑布流 + 2x2 统计卡片 */
@media (max-width: 744px) {
  .collection-page {
    padding: var(--space-base);
  }
  .collection-hero {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-sm);
  }
  .collection-hero__card {
    padding: var(--space-md);
  }
  .collection-hero__number {
    font-size: var(--font-display-md);
  }
  .collection-photo-wall {
    column-count: 2;
    column-gap: var(--space-sm);
  }
  .photo-card {
    margin-bottom: var(--space-sm);
    border-radius: var(--radius-md);
  }
  .collection-filter-bar {
    flex-direction: column;
    gap: var(--space-sm);
  }
  .collection-pills {
    overflow-x: auto;
    flex-wrap: nowrap;
    padding-bottom: var(--space-xs);
    -webkit-overflow-scrolling: touch;
  }
  .collection-pills::-webkit-scrollbar {
    height: 0;
  }
}

/* 手机：2 列瀑布流保持不变 */
@media (max-width: 480px) {
  .collection-photo-wall {
    column-count: 2;
    column-gap: 10px;
  }
  .photo-card {
    margin-bottom: 10px;
    border-radius: var(--radius-md);
  }
  .photo-card__overlay {
    padding: 20px 10px 8px;
  }
  .photo-card__city {
    font-size: 12px;
  }
  .photo-card__date {
    font-size: 10px;
  }
}