/*
  红歌广场页面专属样式 (plaza.css)
*/

/* --- 主布局 --- */
.plaza-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: 2.5rem;
}

/* --- 通用板块标题 --- */
.plaza-section-title {
  font-size: 1.5rem;
  font-weight: 600;
  color: #1f2937;
  margin-bottom: 1.5rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid #e5e7eb;
}

/* --- 左侧：红歌微课 --- */
.article-list {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  max-height: 600px;
  overflow-y: auto;
  padding-right: 0.5rem;
}

.article-item {
  display: block; 
  padding: 1.5rem;
  background-color: rgba(249, 250, 251, 0.8);
  border-radius: 0.75rem;
  border: 1px solid rgba(243, 244, 246, 0.5);
  text-decoration: none;
  transition: box-shadow 0.2s ease-in-out;
}
.article-content {
    flex-grow: 1;
}
.article-item.is-clickable {
    cursor: pointer;
}
.article-item.is-clickable:hover {
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
}

.article-header {
  display: flex;
  align-items: center;
  margin-bottom: 0.75rem;
}

.article-title {
  font-size: 1.125rem;
  font-weight: 600;
  color: #1f2937;
  margin-bottom: 0;
}
.article-summary {
  font-size: 0.875rem;
  line-height: 1.5;
  color: #4b5563;
}

/* --- 播放图标与悬浮提示 --- */
.play-icon-wrapper {
    position: relative;
    flex-shrink: 0;
    margin-right: 0.75rem;
}
.play-icon {
    height: 1.75rem;
    width: 1.75rem;
    color: #fca5a5;
    transition: all 0.2s ease-in-out;
}
.article-item.is-clickable:hover .play-icon {
    color: #ef4444;
    transform: scale(1.1);
}
.play-tooltip {
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%) translateY(-0.5rem);
    background-color: #1f2937;
    color: #ffffff;
    padding: 0.25rem 0.75rem;
    border-radius: 0.375rem;
    font-size: 0.75rem;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease, transform 0.2s ease;
}
.play-icon-wrapper:hover .play-tooltip {
    opacity: 1;
    transform: translateX(-50%) translateY(-0.75rem);
}


/* --- 右侧：史实放映室 (布局修复) --- */
.timeline {
  /* 容器不再需要边框和左内边距 */
  position: relative;
  max-height: 600px;
  overflow-y: auto;
  padding-right: 0.5rem;
  padding-left: 0.5rem;
}
.timeline-item {
  position: relative;
  padding-bottom: 2.5rem;
  /* 每个 item 自己画左边框，形成连接线 */
  border-left: 2px solid #e5e7eb;
  padding-left: 2rem; /* 为内容留出空间 */
}
.timeline-item:last-child {
  padding-bottom: 0.5rem;
  /* 最后一个 item 的线不需要那么长 */
  border-left-color: transparent;
}
/* 更新：时间轴圆点样式 */
.timeline-dot {
  position: absolute;
  left: -0.625rem;
  top: 0.25rem;
  height: 1.25rem;
  width: 1.25rem;
  background-color: #ffffff; /* 初始为白色背景 */
  border: 4px solid #ef4444; /* 红色边框，形成“中空”效果 */
  border-radius: 9999px;
  transition: background-color 0.3s ease-in-out; /* 平滑过渡 */
  cursor: pointer;
}

/* 新增：展开状态下圆点的样式 */
.is-expanded .timeline-dot {
    background-color: #ef4444; /* 变为实心红色 */
}

.timeline-year {
  font-size: 1.25rem;
  font-weight: 600;
  color: #111827;
}
.timeline-description {
  margin-top: 0.25rem;
  color: #6b7280;
  font-size: 0.875rem;
}
/* 移除了 chevron 图标样式 */

/* 更新：可展开的知识卡片 */
.timeline-details {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease-out, margin-top 0.4s ease-out;
    background-color: rgba(249, 250, 251, 0.8); /* 半透明背景 */
    border-radius: 0.5rem;
    font-size: 0.875rem;
    line-height: 1.6;
    color: #4b5563;
}
.is-expanded .timeline-details {
    max-height: 500px;
    margin-top: 1rem;
    padding: 1rem;
    border: 1px solid #e5e7eb;
}

/* --- 通用空列表提示 --- */
.empty-list-text {
  color: #9ca3af;
  text-align: center;
  padding-top: 2rem;
  padding-bottom: 2rem;
}

/* --- 视频播放器弹窗样式 --- */
.video-modal-overlay {
    position: fixed;
    inset: 0;
    background-color: rgba(0, 0, 0, 0.75);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 50;
    transition: opacity 0.3s ease;
}
.video-modal-content {
    position: relative;
    background-color: #000;
    padding: 0.5rem;
    border-radius: 0.75rem;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    width: 90%;
    max-width: 56rem;
}
.close-modal-button {
    position: absolute;
    top: -2.5rem;
    right: 0;
    background: none;
    border: none;
    color: #fff;
    font-size: 2.5rem;
    font-weight: bold;
    cursor: pointer;
    line-height: 1;
    opacity: 0.8;
    transition: opacity 0.2s;
}
.close-modal-button:hover {
    opacity: 1;
}
.video-player {
    width: 100%;
    border-radius: 0.5rem;
    display: block;
}
.hidden {
    display: none;
}