/* ============================
   COURSE DETAIL PAGE
   ============================ */
.course-detail-shell {
  display: grid;
  gap: 28px;
}

.course-detail-banner {
  overflow: hidden;
  border-radius: 28px;
  border: 1px solid var(--dark-border);
  background: var(--dark-card);
  box-shadow: var(--shadow);
}

.course-detail-banner img {
  display: block;
  width: 100%;
  max-height: 520px;
  object-fit: cover;
}

.course-detail-grid {
  display: grid;
  grid-template-columns: minmax(280px, 0.95fr) minmax(0, 1.35fr);
  gap: 24px;
  align-items: start;
}

.course-detail-sidebar,
.course-detail-main {
  display: grid;
  gap: 20px;
}

.course-detail-sidebar {
  position: sticky;
  top: calc(var(--navbar-height) + var(--announcement-height) + 24px);
}

.course-detail-panel {
  padding: 28px;
  border-radius: 24px;
  border: 1px solid var(--dark-border);
  background: var(--dark-card);
  box-shadow: var(--shadow);
}

.course-detail-panel h3 {
  margin-bottom: 16px;
  font-family: var(--font-heading);
  font-size: 1.8rem;
  color: var(--text-primary);
}

.course-detail-panel p + p {
  margin-top: 16px;
}

.course-detail-panel p {
  color: var(--text-secondary);
  line-height: 1.85;
}

.course-description-lead {
  font-size: 1.14rem;
  line-height: 1.95;
  color: var(--text-primary);
}

.contact-panel {
  background:
    linear-gradient(135deg, rgba(245, 166, 35, 0.12), rgba(0, 198, 255, 0.08)),
    var(--dark-card);
}

.contact-panel .btn-primary {
  margin-top: 18px;
}

.detail-bullet-list {
  display: grid;
  gap: 14px;
  color: var(--text-secondary);
}

.detail-bullet-list li {
  position: relative;
  padding-left: 28px;
  line-height: 1.75;
}

.detail-bullet-list li::before {
  content: "\2713";
  position: absolute;
  left: 0;
  top: 0;
  color: var(--orange);
  font-weight: 700;
}

.content-list li::before {
  content: "\2192";
}

.secondary-back {
  background: transparent;
  border: 1px solid var(--dark-border);
  color: var(--text-primary);
  box-shadow: none;
}

.secondary-back:hover {
  color: #fff;
}

@media (max-width: 900px) {
  .course-detail-grid {
    grid-template-columns: 1fr;
  }

  .course-detail-sidebar {
    position: static;
  }
}

@media (max-width: 768px) {
  .course-detail-panel {
    padding: 22px;
  }
}