/* =============================================
   COURSE PAGE STYLES
   ============================================= */

/* ---- COURSE HERO ---- */
.course-hero {
  padding: 72px 40px 56px;
  text-align: center;
  position: relative;
  width: 100%;
}

.course-hero::before {
  content: '';
  position: absolute;
  top: -100px;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 800px;
  background: radial-gradient(circle, rgba(59,130,246,0.06) 0%, transparent 70%);
  pointer-events: none;
}

.course-hero h1 {
  font-size: 3.2rem;
  font-weight: 900;
  letter-spacing: -0.04em;
  margin: 0 0 18px;
  line-height: 1.1;
}

.course-hero h1 .line1 {
  display: block;
  color: var(--muted);
  font-size: 1.2rem;
  font-weight: 600;
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.course-hero h1 .line2 { display: block; }
.course-hero h1 .accent {
  background: linear-gradient(135deg, #3B82F6 0%, #22C55E 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.course-hero p {
  color: var(--muted);
  font-size: 1.02rem;
  line-height: 1.75;
  max-width: 600px;
  margin: 0 auto 32px;
}

.course-stats {
  display: flex;
  justify-content: center;
  gap: 48px;
  margin-top: 32px;
}

.course-stat {
  text-align: center;
}

.course-stat .num {
  display: block;
  font-size: 2rem;
  font-weight: 800;
  color: var(--green);
  letter-spacing: -0.02em;
}

.course-stat .label {
  display: block;
  color: var(--muted);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-top: 4px;
}

/* ---- MODULE GRID ---- */
.module-grid {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 32px;
}

.module-card {
  display: flex;
  align-items: stretch;
  gap: 24px;
  padding: 28px 32px;
  background: var(--panel-solid);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  transition: all var(--transition);
  text-decoration: none;
  position: relative;
  overflow: hidden;
}

.module-card::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--gradient-green);
  opacity: 0;
  transition: opacity var(--transition);
}

.module-card:hover {
  border-color: var(--border-hover);
  transform: translateX(4px);
  box-shadow: var(--shadow), var(--shadow-glow);
}

.module-card:hover::before { opacity: 1; }

.module-num {
  font-size: 2rem;
  font-weight: 900;
  color: var(--border-light);
  min-width: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  letter-spacing: -0.03em;
  transition: color var(--transition);
}

.module-card:hover .module-num { color: var(--green); }

.module-info { flex: 1; }

.module-info h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 6px;
  letter-spacing: -0.01em;
}

.module-info p {
  color: var(--muted);
  font-size: 0.85rem;
  line-height: 1.65;
  margin-bottom: 12px;
}

.module-meta {
  display: flex;
  align-items: center;
  gap: 12px;
}

.module-time {
  font-size: 0.72rem;
  color: var(--muted);
}

/* ---- LESSON PAGE ---- */
.lesson-hero {
  padding: 48px 0 32px;
  border-bottom: 1px solid var(--border);
}

.lesson-hero h1 {
  font-size: 2.2rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 8px;
}

.lesson-hero .module-label {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--blue);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 12px;
}

.lesson-hero p {
  color: var(--muted);
  font-size: 0.95rem;
  max-width: 640px;
  line-height: 1.7;
}

.lesson-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 0;
  margin-bottom: 32px;
  border-bottom: 1px solid var(--border);
}

.lesson-nav a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--muted);
  transition: color var(--transition);
}

.lesson-nav a:hover { color: var(--green); }

/* ---- LESSON CONTENT ---- */
.lesson-content {
  max-width: 780px;
  margin: 0 auto;
  padding: 0 0 60px;
}

.lesson-content h2 {
  font-size: 1.6rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin: 48px 0 16px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  color: var(--text);
}

.lesson-content h2:first-child {
  border-top: none;
  margin-top: 0;
  padding-top: 0;
}

.lesson-content h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin: 32px 0 12px;
  color: var(--text);
}

.lesson-content h4 {
  font-size: 0.95rem;
  font-weight: 700;
  margin: 24px 0 8px;
  color: var(--text-secondary);
}

.lesson-content p {
  color: var(--text-secondary);
  font-size: 0.92rem;
  line-height: 1.85;
  margin-bottom: 16px;
}

.lesson-content ul, .lesson-content ol {
  margin: 12px 0 20px 24px;
  color: var(--text-secondary);
  font-size: 0.92rem;
  line-height: 1.85;
}

.lesson-content ul { list-style: disc; }
.lesson-content ol { list-style: decimal; }
.lesson-content li { margin-bottom: 8px; }

.lesson-content strong { color: var(--text); }
.lesson-content em { color: var(--green); font-style: italic; }

.lesson-content blockquote {
  border-left: 3px solid var(--green);
  padding: 16px 20px;
  margin: 20px 0;
  background: var(--green-dim);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-style: italic;
  color: var(--text-secondary);
}

.lesson-content .key-concept {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px 24px;
  margin: 24px 0;
}

.lesson-content .key-concept h4 {
  color: var(--green);
  margin: 0 0 8px;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.lesson-content .warning-box {
  background: var(--red-dim);
  border: 1px solid rgba(239,68,68,0.2);
  border-radius: var(--radius-lg);
  padding: 20px 24px;
  margin: 24px 0;
}

.lesson-content .warning-box h4 {
  color: var(--red);
  margin: 0 0 8px;
}

.lesson-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
  font-size: 0.85rem;
}

.lesson-content th {
  text-align: left;
  padding: 10px 14px;
  background: var(--panel);
  border: 1px solid var(--border);
  font-weight: 700;
  color: var(--text);
}

.lesson-content td {
  padding: 10px 14px;
  border: 1px solid var(--border);
  color: var(--text-secondary);
}

.lesson-content .lesson-complete {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: 32px;
  margin-top: 48px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  text-align: center;
}

.lesson-complete .btn { min-width: 160px; }

/* ---- RESPONSIVE ---- */
@media (max-width: 768px) {
  .course-hero { padding: 48px 16px 40px; }
  .course-hero h1 { font-size: 2.2rem; }
  .course-stats { gap: 24px; }
  .module-card { padding: 20px; gap: 16px; }
  .module-num { font-size: 1.4rem; min-width: 40px; }
  .lesson-content { padding: 0 0 40px; }
}

@media (max-width: 480px) {
  .course-hero h1 { font-size: 1.8rem; }
  .module-card { flex-direction: column; gap: 8px; }
}