/* ==========================================================================
   SHARED COURSE PAGE — "Course Player"
   Uses design tokens from _design_tokens.css
   ========================================================================== */

body:has(.sc-layout) {
  background: var(--sl-cream);
}

.sc-layout {
  font-family: var(--font-sans);
}

/* --------------------------------------------------------------------------
   COMPACT HERO
   -------------------------------------------------------------------------- */

.sc-hero {
  padding: clamp(1.5rem, 3vw, 2.5rem) 0 clamp(1rem, 2vw, 1.5rem);
  position: relative;
  overflow: hidden;
}

.sc-hero::before {
  content: '';
  position: absolute;
  top: -80%;
  right: -15%;
  width: 45%;
  height: 280%;
  background: var(--sl-teal-light);
  border-radius: 50%;
  opacity: 0.4;
  pointer-events: none;
}

.sc-hero-inner {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: var(--space-sm);
}

.sc-hero-content {
  flex: 1;
  min-width: 0;
}

.sc-hero-back {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  font-size: 0.8125rem;
  color: var(--sl-gray);
  text-decoration: none;
  margin-bottom: var(--space-sm);
  transition: color var(--transition-fast);
}

.sc-hero-back:hover {
  color: var(--sl-teal);
}

.sc-hero-back i {
  font-size: 1rem;
  transition: transform var(--transition-fast);
}

.sc-hero-back:hover i {
  transform: translateX(-2px);
}

/* --------------------------------------------------------------------------
   BADGE (course depth)
   -------------------------------------------------------------------------- */

.sc-badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-full);
  font-size: 0.6875rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: 0.625rem;
}

.sc-badge--introductory {
  background: rgba(1, 129, 141, 0.12);
  color: var(--sl-teal-dark);
  border: 1px solid rgba(1, 129, 141, 0.15);
}

.sc-badge--middle {
  background: rgba(224, 122, 95, 0.12);
  color: var(--sl-coral-dark);
  border: 1px solid rgba(224, 122, 95, 0.15);
}

.sc-badge--advanced {
  background: rgba(123, 31, 162, 0.1);
  color: #6A1B9A;
  border: 1px solid rgba(123, 31, 162, 0.15);
}

/* --------------------------------------------------------------------------
   HERO TITLE, TAGS, DESCRIPTION, ACTIONS (animated fade-up)
   -------------------------------------------------------------------------- */

.sc-hero-title {
  font-family: var(--font-serif);
  font-size: clamp(1.5rem, 3.5vw, 2.25rem);
  line-height: 1.2;
  color: var(--sl-charcoal);
  font-weight: 400;
  letter-spacing: -0.02em;
  margin: 0 0 0.5rem;
  opacity: 0;
  animation: sc-fade-up 0.5s cubic-bezier(0.4, 0, 0.2, 1) 0.1s forwards;
}

.sc-hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.375rem;
  margin-bottom: 0.5rem;
  opacity: 0;
  animation: sc-fade-up 0.5s cubic-bezier(0.4, 0, 0.2, 1) 0.2s forwards;
}

.sc-tag {
  display: inline-block;
  padding: 0.1875rem 0.625rem;
  border-radius: var(--radius-full);
  font-size: 0.6875rem;
  font-weight: 500;
  background: white;
  color: var(--sl-gray);
  border: 1px solid rgba(0, 0, 0, 0.06);
}

.sc-hero-desc {
  font-size: 0.9375rem;
  line-height: 1.6;
  color: var(--sl-gray);
  max-width: 60ch;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  margin: 0;
  opacity: 0;
  animation: sc-fade-up 0.5s cubic-bezier(0.4, 0, 0.2, 1) 0.3s forwards;
}

.sc-hero-actions {
  flex-shrink: 0;
  opacity: 0;
  animation: sc-fade-up 0.5s cubic-bezier(0.4, 0, 0.2, 1) 0.35s forwards;
}

@keyframes sc-fade-up {
  from { opacity: 0; transform: translateY(10px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* --------------------------------------------------------------------------
   TWO-COLUMN BODY (sidebar + content)
   -------------------------------------------------------------------------- */

.sc-body {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: var(--space-lg);
  padding-bottom: var(--space-2xl);
}

/* --------------------------------------------------------------------------
   SIDEBAR (sticky, scrollable)
   -------------------------------------------------------------------------- */

.sc-sidebar {
  position: sticky;
  top: 5rem;
  max-height: calc(100vh - 6rem);
  overflow-y: auto;
  padding-right: var(--space-sm);
  scrollbar-width: thin;
  scrollbar-color: var(--sl-teal-light) transparent;
}

.sc-sidebar::-webkit-scrollbar {
  width: 4px;
}

.sc-sidebar::-webkit-scrollbar-track {
  background: transparent;
}

.sc-sidebar::-webkit-scrollbar-thumb {
  background: var(--sl-teal-light);
  border-radius: var(--radius-full);
}

.sc-nav-category {
  margin-bottom: var(--space-xs);
}

.sc-nav-category-title {
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--sl-charcoal);
  padding: 0.5rem 0;
  margin: 0;
  border-bottom: 1px solid var(--sl-teal-light);
  letter-spacing: 0.01em;
}

.sc-nav-list {
  list-style: none;
  padding: 0.375rem 0 0.625rem;
  margin: 0;
}

.sc-nav-link {
  display: block;
  padding: 0.375rem 0.75rem;
  margin: 1px 0;
  font-size: 0.8125rem;
  color: var(--sl-gray);
  text-decoration: none;
  border-radius: var(--radius-sm);
  border-left: 3px solid transparent;
  transition: all var(--transition-fast);
  line-height: 1.4;
}

.sc-nav-link:hover {
  color: var(--sl-teal);
  background: rgba(1, 129, 141, 0.04);
}

.sc-nav-link--active {
  color: var(--sl-teal-dark);
  background: var(--sl-teal-light);
  border-left-color: var(--sl-teal);
  font-weight: 500;
}

/* --------------------------------------------------------------------------
   MOBILE ACCORDION (hidden by default, shown < 768px)
   -------------------------------------------------------------------------- */

.sc-accordion {
  display: none;
  margin-bottom: var(--space-md);
}

.sc-accordion-toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 0.75rem 1rem;
  background: white;
  border: 1px solid rgba(0, 0, 0, 0.06);
  border-radius: var(--radius-md);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--sl-charcoal);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.sc-accordion-toggle:hover {
  border-color: var(--sl-teal);
}

.sc-accordion-toggle i {
  transition: transform var(--transition-normal);
  font-size: 0.75rem;
  color: var(--sl-gray);
}

.sc-accordion-toggle[aria-expanded="true"] i {
  transform: rotate(180deg);
}

.sc-accordion-body {
  background: white;
  border: 1px solid rgba(0, 0, 0, 0.06);
  border-top: none;
  border-radius: 0 0 var(--radius-md) var(--radius-md);
  padding: 0.5rem;
  max-height: 50vh;
  overflow-y: auto;
}

/* --------------------------------------------------------------------------
   VIDEO CONTENT
   -------------------------------------------------------------------------- */

.sc-content {
  min-width: 0;
}

.sc-subtopic-title {
  font-family: var(--font-serif);
  font-size: clamp(1.25rem, 2.5vw, 1.75rem);
  color: var(--sl-charcoal);
  font-weight: 400;
  margin: 0 0 var(--space-sm);
  letter-spacing: -0.01em;
}

.sc-explanation {
  font-size: 0.9375rem;
  line-height: 1.7;
  color: var(--sl-gray);
  margin-bottom: var(--space-xl);
  max-width: 72ch;
}

.sc-video-card {
  background: white;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid rgba(0, 0, 0, 0.04);
  box-shadow: var(--shadow-sm);
  margin-bottom: var(--space-xl);
  transition: box-shadow var(--transition-normal);
}

.sc-video-card:hover {
  box-shadow: var(--shadow-md);
}

.sc-video-wrapper {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  background: var(--sl-charcoal);
}

.sc-video-wrapper .embed-responsive-item {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

.sc-video-title {
  padding: 0.875rem 1.25rem;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--sl-charcoal);
  margin: 0;
  border-top: 1px solid rgba(0, 0, 0, 0.04);
}

/* --------------------------------------------------------------------------
   RESPONSIVE
   -------------------------------------------------------------------------- */

@media (max-width: 991px) {
  .sc-body {
    grid-template-columns: 220px 1fr;
    gap: var(--space-md);
  }

  .sc-hero::before {
    width: 60%;
    top: -60%;
    right: -20%;
  }
}

@media (max-width: 767px) {
  .sc-body {
    grid-template-columns: 1fr;
  }

  .sc-sidebar {
    display: none;
  }

  .sc-accordion {
    display: block;
  }

  .sc-hero-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .sc-hero::before {
    display: none;
  }
}

/* --------------------------------------------------------------------------
   REDUCED MOTION
   -------------------------------------------------------------------------- */

@media (prefers-reduced-motion: reduce) {
  .sc-hero-title,
  .sc-hero-tags,
  .sc-hero-desc,
  .sc-hero-actions {
    animation: none;
    opacity: 1;
    transform: none;
  }

  .sc-video-card,
  .sc-nav-link,
  .sc-hero-back i,
  .sc-accordion-toggle i {
    transition: none;
  }
}