:root {
  --primary: #1DD6D1;
  --dark: #222;
  --gray: #666;
  --light-gray: #999;
  --bg: #fff;
  --soft: #f6f8f9;
}

body {
  font-family: 'Roboto', sans-serif;
  background: var(--soft);
  color: var(--dark);
}

.detail-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 30px 20px 80px;
}

.breadcrumb {
  font-size: 14px;
  color: var(--light-gray);
  margin: 10px 0 20px;
}

.breadcrumb span {
  color: var(--dark);
}

.detail-top {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  gap: 30px;
  align-items: start;
}

.player-card {
  background: #000;
  border-radius: 18px;
  padding: 16px;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.2);
}

.player-frame {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  border-radius: 12px;
  overflow: hidden;
  background: #000;
}

.player-frame iframe {
  width: 100%;
  height: 100%;
  border: 0;
  display: block;
}

.preview-note {
  color: #e0e0e0;
  font-size: 13px;
  margin-top: 12px;
}

.info-card {
  position: sticky;
  top: 110px;
  background: #fff;
  border-radius: 18px;
  padding: 24px;
  box-shadow: 0 10px 26px rgba(0, 0, 0, 0.12);
}

.info-card h1 {
  font-size: 25px;
  font-weight: 700;
  margin: 0 0 12px;
  word-wrap: break-word;
  overflow-wrap: break-word;
  hyphens: auto;
}

.info-meta {
  font-size: 14px;
  color: var(--gray);
  margin-bottom: 10px;
}

.rating {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: #f9a825;
  margin-bottom: 16px;
}

.rating span {
  color: var(--gray);
}

.price {
  font-size: 28px;
  font-weight: 700;
  color: var(--primary);
  margin: 12px 0 18px;
}

.btn-primary {
  display: block;
  width: 100%;
  text-align: center;
  background: var(--primary);
  color: #fff;
  padding: 14px 20px;
  border-radius: 25px;
  font-weight: 700;
  text-decoration: none;
  transition: background 0.2s ease;
  box-sizing: border-box;
  white-space: normal;
  word-wrap: break-word;
}

.btn-primary:hover {
  background: #17b8b3;
}

.badge-owned {
  display: inline-block;
  background: #2e7d32;
  color: #fff;
  padding: 6px 12px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
  margin-bottom: 12px;
}

.info-list {
  margin-top: 20px;
  padding-top: 20px;
  border-top: 1px solid #eee;
}

.info-list li {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  color: var(--gray);
  margin-bottom: 10px;
}

.info-list li::before {
  content: '•';
  color: var(--primary);
  font-size: 18px;
}

.section {
  margin-top: 50px;
  background: #fff;
  border-radius: 18px;
  padding: 28px;
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.08);
}

.tabs {
  display: flex;
  gap: 16px;
  border-bottom: 1px solid #eee;
  margin-bottom: 20px;
}

.tabs button {
  background: none;
  border: none;
  padding: 10px 6px;
  font-weight: 600;
  color: var(--gray);
  cursor: pointer;
  border-bottom: 3px solid transparent;
}

.tabs button.active {
  color: var(--dark);
  border-color: var(--primary);
}

.tab-panel {
  display: none;
}

.tab-panel.active {
  display: block;
}

.section h3 {
  margin-top: 24px;
  margin-bottom: 12px;
  font-size: 20px;
}

.learn-list li {
  list-style: none;
  margin-bottom: 10px;
  padding-left: 26px;
  position: relative;
}

.learn-list li::before {
  content: '✓';
  position: absolute;
  left: 0;
  top: 0;
  color: var(--primary);
  font-weight: 700;
}

.prereq-list li {
  margin-bottom: 8px;
}

.accordion details {
  border: 1px solid #eee;
  border-radius: 12px;
  margin-bottom: 12px;
  padding: 12px 16px;
}

.accordion summary {
  cursor: pointer;
  font-weight: 600;
  list-style: none;
}

.accordion summary::-webkit-details-marker {
  display: none;
}

.accordion .chapter-meta {
  color: var(--gray);
  font-size: 13px;
  margin-top: 4px;
}

.lesson-list {
  margin-top: 12px;
  padding-left: 0;
}

.lesson-list li {
  list-style: none;
  display: flex;
  justify-content: space-between;
  padding: 8px 0;
  border-bottom: 1px dashed #eee;
  font-size: 14px;
}

.lesson-list li:last-child {
  border-bottom: none;
}

.lesson-list .lock {
  color: #d32f2f;
}

.lesson-list .play {
  color: var(--primary);
}

.reviews {
  display: grid;
  gap: 18px;
}

.review-card {
  display: flex;
  gap: 16px;
  background: #f9fbfb;
  border-radius: 14px;
  padding: 16px;
}

.review-card img {
  width: 54px;
  height: 54px;
  border-radius: 50%;
  object-fit: cover;
}

.review-card h4 {
  margin: 0 0 6px;
}

.similar-section {
  margin-top: 60px;
}

.similar-section h2 {
  margin-bottom: 20px;
}

.similar-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

@media (max-width: 1024px) {
  .detail-top {
    grid-template-columns: 1fr;
  }

  .info-card {
    position: static;
  }

  .similar-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 768px) {
  .detail-container {
    padding: 20px 16px 60px;
  }

  .similar-grid {
    grid-template-columns: 1fr;
  }
}