/* lecture.css - 讲座详情页样式 */
:root {
  --lecture-primary: #006AB6;
  --lecture-primary-light: rgba(0, 106, 182, 0.06);
  --lecture-accent: #DD2400;
  --lecture-text-main: #2c3e50;
  --lecture-text-muted: #6c757d;
  --lecture-bg-card: #ffffff;
  --lecture-border: rgba(0, 0, 0, 0.08);
  --lecture-shadow: 0 4px 20px rgba(0, 106, 182, 0.08);
  --lecture-radius: 12px;
}

/* 左右布局 */
.lecture-layout {
  display: flex;
  gap: 3rem;
  align-items: flex-start;
}

/* 左侧信息栏 */
.lecture-sidebar {
  width: 50rem;
  flex-shrink: 0;
  position: sticky;
  top: 10rem;
}

.lecture-sidebar__inner {
  background: var(--lecture-bg-card);
  border: 1px solid var(--lecture-border);
  border-radius: var(--lecture-radius);
  padding: 3rem 2.5rem;
  box-shadow: var(--lecture-shadow);
  position: relative;
  overflow: hidden;
}

.lecture-sidebar__inner::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 5px;
  height: 100%;
  background: linear-gradient(to bottom, var(--lecture-primary), #4facfe);
}

.lecture-sidebar__title {
  font-size: 2.4rem;
  font-weight: 700;
  color: var(--lecture-text-main);
  line-height: 1.5;
  margin: 0 0 2.5rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--lecture-border);
}

.lecture-sidebar__meta {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

/* 元信息条目 */
.meta-item {
  display: flex;
  align-items: flex-start;
  gap: 1.4rem;
}

.meta-item__icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 5.6rem;
  height: 5.6rem;
  background: var(--lecture-primary-light);
  color: var(--lecture-primary);
  border-radius: 10px;
  flex-shrink: 0;
  transition: all 0.3s ease;
}

.meta-item__icon .iconfont {
  font-size: 2.4rem;
}

.meta-item:hover .meta-item__icon {
  background: var(--lecture-primary);
  color: #fff;
  transform: scale(1.05);
}

.meta-item__body {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  min-width: 0;
}

.meta-item__label {
  font-size: 1.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--lecture-text-muted);
}

.meta-item__value {
  font-size: 1.7rem;
  font-weight: 500;
  color: var(--lecture-text-main);
  line-height: 1.5;
}

.meta-item__value time {
  font-family: 'SF Mono', Consolas, Monaco, monospace;
  letter-spacing: -0.3px;
}

/* 右侧内容区 */
.lecture-main {
  flex: 1;
  min-width: 0;
}

/* 页面容器 */
.lecture-page-container {
  margin: 0 auto;
  position: relative;
}

.lecture-page-container::before {
  content: '';
  position: absolute;
  top: -50px;
  right: -100px;
  width: 300px;
  height: 300px;
  background: radial-gradient(circle, var(--lecture-primary-light) 0%, rgba(255,255,255,0) 70%);
  z-index: -1;
  border-radius: 50%;
  pointer-events: none;
}

/* 讲座内容样式 */
.lecture-content {
  line-height: 2;
  font-size: 1.7rem;
  color: var(--lecture-text-main);
  letter-spacing: 0.3px;
}

.lecture-content p {
  margin-bottom: 1.5em;
}

.lecture-content strong {
  color: var(--lecture-primary);
  font-weight: 600;
}

/* 响应式：平板及以下切换为上下堆叠 */
@media only screen and (max-width: 75em) {
  .lecture-layout {
    flex-direction: column;
    gap: 2rem;
  }

  .lecture-sidebar {
    width: 100%;
    position: static;
  }

  .lecture-sidebar__inner {
    padding: 2rem;
  }

  .lecture-sidebar__title {
    font-size: 1.8rem;
    margin-bottom: 2rem;
    padding-bottom: 1.5rem;
  }

  .lecture-sidebar__meta {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 1.5rem;
  }

  .meta-item {
    flex: 1;
    min-width: 20rem;
  }
}

@media only screen and (max-width: 48em) {
  .lecture-sidebar__meta {
    flex-direction: column;
    gap: 1.5rem;
  }

  .meta-item {
    min-width: 0;
  }

  .meta-item__icon {
    width: 4.4rem;
    height: 4.4rem;
  }

  .meta-item__icon .iconfont {
    font-size: 2rem;
  }

  .meta-item__label,
  .meta-item__value {
    font-size: 1.5rem;
  }

  .lecture-sidebar__inner {
    padding: 1.5rem 1rem;
  }

  .lecture-sidebar__title {
    font-size: 1.6rem;
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
  }

  .lecture-content {
    font-size: 1.6rem;
  }

  .lecture-page-container::before {
    display: none;
  }
}