/* Blueprint Academy - Topic details specific styles */

.topic-detail-page {
  padding: 60px 0 100px;
}

.back-link-container {
  margin-bottom: 32px;
}

.back-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--text-secondary);
  font-weight: 600;
  font-size: 0.95rem;
  padding: 8px 16px;
  border-radius: 6px;
  border: 1px solid var(--border-color);
  background-color: var(--bg-primary);
  transition: var(--transition);
}

.back-btn:hover {
  color: var(--primary);
  border-color: var(--primary);
  background-color: var(--primary-light);
  transform: translateX(-2px);
}

.topic-layout {
  display: grid;
  grid-template-columns: 1.8fr 1.2fr;
  gap: 48px;
  align-items: start;
}

/* Left Column: Video and Main information */
.topic-main-content {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.topic-title-section {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.topic-title-section h1 {
  font-size: 2.5rem;
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.topic-short-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Active Lecture Video Panel */
.active-lecture-panel {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.active-lecture-panel h2 {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

.video-wrapper {
  position: relative;
  padding-bottom: 56.25%; /* 16:9 Aspect Ratio */
  height: 0;
  overflow: hidden;
  border-radius: 12px;
  background-color: #000000;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
}

.video-wrapper iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
}

/* Right Column: Playlist & PDF Sidebars */
.topic-sidebar {
  display: flex;
  flex-direction: column;
  gap: 32px;
  position: sticky;
  top: 110px;
}

.sidebar-card {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: 32px;
}

.sidebar-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 20px;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.sidebar-card h3 svg {
  color: var(--primary);
  width: 20px;
  height: 20px;
}

/* Playlist items list */
.playlist-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.playlist-item {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 14px;
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 14px 16px;
  cursor: pointer;
  text-align: left;
  font-family: inherit;
  transition: var(--transition);
}

.playlist-item:hover {
  border-color: var(--primary);
  background-color: var(--primary-light);
  transform: translateY(-1px);
}

.playlist-item.active {
  background-color: var(--primary-light);
  border-color: var(--primary);
  box-shadow: var(--shadow-sm);
}

.playlist-number {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.75rem;
  font-weight: 700;
  background-color: var(--bg-secondary);
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  padding: 4px 8px;
  border-radius: 4px;
  flex-shrink: 0;
}

.playlist-item.active .playlist-number {
  background-color: var(--primary);
  color: #FFFFFF;
  border-color: var(--primary);
}

.playlist-title {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.playlist-item.active .playlist-title {
  color: var(--primary);
}

/* Materials Download section */
.materials-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.material-item-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 14px 16px;
  transition: var(--transition);
  text-decoration: none;
  cursor: pointer;
}

.material-item-card:hover {
  border-color: var(--primary);
  background-color: var(--primary-light);
  transform: translateY(-1px);
}

.material-item-info {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 1 1 auto;
  min-width: 0; /* allows overflow truncation */
}

.material-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  color: #EF4444; /* PDF color red */
  flex-shrink: 0;
}

.material-icon svg {
  width: 22px;
  height: 22px;
}

.material-item-info h4 {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.download-link-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  color: var(--text-secondary);
  background-color: var(--bg-secondary);
  transition: var(--transition);
  flex-shrink: 0;
}

.material-item-card:hover .download-link-btn {
  background-color: var(--primary);
  color: #FFFFFF;
}

/* Responsive sidebar */
@media (max-width: 900px) {
  .topic-layout {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .topic-sidebar {
    position: static;
  }
}

/* Lecture Syllabus Panel Styling */
.lecture-syllabus-panel {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: 32px;
  margin-top: 32px;
  box-shadow: var(--shadow-sm);
}

.lecture-syllabus-panel h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-top: 24px;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.lecture-syllabus-panel h3:first-of-type {
  margin-top: 0;
}

.lecture-syllabus-panel ul {
  list-style-type: disc;
  margin-left: 20px;
  margin-bottom: 20px;
}

.lecture-syllabus-panel ul:last-of-type {
  margin-bottom: 0;
}

.lecture-syllabus-panel ul li {
  font-size: 0.95rem;
  color: var(--text-secondary);
  margin-bottom: 6px;
  line-height: 1.6;
}