/* ─── Course Sidebar ─── */
.course-sidebar .sidebar-brand {
  flex-direction: column;
  align-items: flex-start;
  gap: 0.25rem;
}

.course-sidebar-title {
  font-size: 0.78rem;
  color: var(--text-secondary);
  font-weight: 500;
  line-height: 1.3;
}

.sidebar-progress {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--card-border);
}

.sidebar-progress .progress-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.4rem;
}

.sidebar-progress .progress-pct {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--primary);
}

.sidebar-progress .progress-text {
  font-size: 0.72rem;
  color: var(--text-secondary);
}

.sidebar-progress .progress-bar {
  height: 4px;
  background: rgba(0, 0, 0, 0.06);
  border-radius: 4px;
  overflow: hidden;
}

.sidebar-progress .progress-fill {
  height: 100%;
  background: var(--primary);
  border-radius: 4px;
  transition: width 0.5s var(--ease);
}

/* ─── Module List ─── */
.module-list {
  overflow-y: auto;
  padding: 0.5rem;
}

.module-group {
  margin-bottom: 0.5rem;
}

.module-header {
  padding: 0.4rem 0.5rem;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-tertiary);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.lesson-item {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.45rem 0.5rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 0.82rem;
  transition: background 0.15s, color 0.15s;
}

.lesson-item:hover {
  background: rgba(0, 0, 0, 0.03);
  color: var(--text-primary);
}

.lesson-item.active {
  background: var(--primary-glow);
  color: var(--primary);
}

.lesson-item.completed {
  color: var(--success);
}

.lesson-check {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  border: 2px solid var(--text-tertiary);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 0.6rem;
}

.lesson-item.completed .lesson-check {
  background: var(--success);
  border-color: var(--success);
  color: white;
}

.lesson-item.active .lesson-check {
  border-color: var(--primary);
  background: var(--primary);
  color: white;
}

.lesson-type {
  font-size: 0.65rem;
  color: var(--text-tertiary);
  margin-left: auto;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

/* ─── Course Main Content ─── */
.course-main {
  max-width: 820px;
  margin: 0 auto;
  padding: 3rem 2rem;
}

.lesson-header {
  margin-bottom: 2rem;
}

.lesson-header h1 {
  font-size: 1.8rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.3;
  margin-bottom: 0.5rem;
}

.lesson-desc {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ─── Lesson Body ─── */
.lesson-body {
  margin-bottom: 2rem;
}

.lesson-body p {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text-primary);
  margin-bottom: 1rem;
}

.lesson-body h2 {
  font-size: 1.35rem;
  font-weight: 700;
  margin: 2rem 0 0.75rem;
  letter-spacing: -0.01em;
}

.lesson-body h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin: 1.5rem 0 0.5rem;
}

.lesson-body ul,
.lesson-body ol {
  margin: 0.5rem 0 1rem 1.5rem;
}

.lesson-body li {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.lesson-body blockquote {
  border-left: 3px solid var(--primary);
  padding: 0.75rem 1rem;
  margin: 1.25rem 0;
  background: rgba(0, 0, 0, 0.02);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-style: italic;
  color: var(--text-secondary);
}

.lesson-body .callout {
  background: var(--primary-glow);
  border: 1px solid rgba(230, 57, 70, 0.12);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  margin: 1.25rem 0;
  font-size: 0.9rem;
  color: var(--text-primary);
}

/* ─── Quiz ─── */
.quiz-question {
  background: var(--bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  margin-bottom: 1.25rem;
}

.quiz-question h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

.quiz-option {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.65rem 0.9rem;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-sm);
  margin-bottom: 0.5rem;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s;
  font-size: 0.9rem;
}

.quiz-option:hover {
  border-color: var(--text-tertiary);
}

.quiz-option input[type="radio"],
.quiz-option input[type="checkbox"] {
  accent-color: var(--primary);
}

.quiz-option.correct {
  border-color: var(--success);
  background: var(--success-bg);
}

.quiz-option.incorrect {
  border-color: var(--error);
  background: var(--error-bg);
}

.quiz-feedback {
  margin-top: 0.5rem;
  font-size: 0.85rem;
  padding: 0.5rem 0.75rem;
  border-radius: var(--radius-sm);
  display: none;
}

.quiz-feedback.show { display: block; }

.quiz-feedback.correct {
  background: var(--success-bg);
  color: var(--success);
}

.quiz-feedback.incorrect {
  background: var(--error-bg);
  color: var(--error);
}

/* ─── Video Placeholder ─── */
.video-placeholder {
  width: 100%;
  aspect-ratio: 16 / 9;
  background: #1d1d1f;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255, 255, 255, 0.3);
  font-size: 0.9rem;
  margin-bottom: 1.5rem;
}



.lesson-nav {
  display: flex;
  gap: 0.75rem;
}

.lesson-nav button {
  padding: 0.5rem 1.25rem;
  border-radius: var(--radius-pill);
  border: 1px solid var(--card-border);
  background: var(--bg-secondary);
  color: var(--text-primary);
  font-size: 0.85rem;
  font-weight: 500;
  cursor: pointer;
  font-family: inherit;
  transition: background 0.15s;
}

.lesson-nav button:hover { background: rgba(0, 0, 0, 0.035); }

.loading-spinner {
  width: 32px;
  height: 32px;
  border: 3px solid var(--card-border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
  margin: 3rem auto;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ─── Case Study Options ─── */
.case-option:hover {
  border-color: var(--primary) !important;
  background: var(--primary-glow) !important;
}

.case-option:disabled {
  opacity: 0.5;
  cursor: default;
}

.case-progress {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.case-progress .progress-bar {
  flex: 1;
}

/* ─── Certificate Area ─── */
#certificate-area .btn {
  display: inline-flex; align-items: center; gap: 0.4rem;
  padding: 0.6rem 1.25rem; border-radius: var(--radius-pill);
  border: none; font-size: 0.85rem; font-weight: 600;
  cursor: pointer; font-family: inherit;
  transition: all 0.15s;
}
#certificate-area .btn-primary {
  background: var(--primary); color: white;
}
#certificate-area .btn-primary:hover {
  background: var(--primary-dark); transform: translateY(-1px);
}
#certificate-area .btn-secondary {
  background: var(--bg-secondary); color: var(--text-primary);
  border: 1px solid var(--card-border);
}
#certificate-area .btn-secondary:hover {
  background: var(--primary-glow); border-color: var(--primary); color: var(--primary);
}

/* ─── Lesson Actions ─── */
.lesson-actions {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding-top: 2rem;
  border-top: 1px solid var(--card-border);
}