/* =============================================
   SMART LOAD ACADEMY - LESSON SIDEBAR
   ============================================= */

.lesson-sidebar {
  position: fixed;
  top: 52px;
  left: 0;
  width: 280px;
  height: calc(100vh - 52px);
  background: rgba(15, 15, 20, 0.97);
  backdrop-filter: blur(20px);
  border-right: 1px solid rgba(255, 255, 255, 0.1);
  overflow-y: auto;
  z-index: 300;
  transform: translateX(-100%);
  transition: transform 0.3s ease;
}

.lesson-sidebar.open {
  transform: translateX(0);
}

.lesson-sidebar-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 1.25rem 1.25rem 1rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.lesson-sidebar-module {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: #888;
  margin-bottom: 0.25rem;
}

.lesson-sidebar-title {
  font-size: 1rem;
  font-weight: 800;
  color: #ffffff;
  line-height: 1.3;
}

.lesson-sidebar-close {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.08);
  border: none;
  color: #fff;
  cursor: pointer;
  font-size: 1rem;
}

.lesson-sidebar-list {
  padding: 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.lesson-sidebar-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 0.875rem;
  border-radius: 0.625rem;
  border: 1px solid transparent;
  text-decoration: none;
  color: #d0d0d0;
  transition: all 0.2s ease;
}

.lesson-sidebar-item:hover {
  background: rgba(255, 255, 255, 0.05);
  border-color: rgba(255, 255, 255, 0.1);
}

.lesson-sidebar-item.active {
  background: rgba(0, 217, 255, 0.1);
  border-color: rgba(0, 217, 255, 0.4);
  color: #ffffff;
}

.lesson-sidebar-marker {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  border: 2px solid rgba(255, 255, 255, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.7rem;
  font-weight: 800;
  color: #888;
}

.lesson-sidebar-item.active .lesson-sidebar-marker {
  border-color: #00D9FF;
  color: #00D9FF;
}

.lesson-sidebar-item.completed .lesson-sidebar-marker {
  border-color: #64C864;
  background: rgba(100, 200, 100, 0.15);
  color: #64C864;
}

.lesson-sidebar-item-title {
  font-size: 0.875rem;
  font-weight: 600;
  line-height: 1.3;
}

.lesson-sidebar-item-time {
  font-size: 0.75rem;
  color: #888;
  margin-top: 0.125rem;
}

.lesson-sidebar-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: linear-gradient(135deg, #00D9FF, #FF6B35);
  color: #000;
  border: none;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.4);
  font-size: 1.4rem;
  cursor: pointer;
  z-index: 250;
}

.lesson-sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  z-index: 280;
}

.lesson-sidebar-overlay.open {
  display: block;
}

/* ==== DESKTOP: sidebar always visible, pushes content over ==== */
@media (min-width: 1280px) {
  .lesson-sidebar {
    transform: none;
    z-index: 150;
  }

  body .lesson-container {
    margin-left: 300px;
    margin-right: auto;
  }

  .lesson-sidebar-close,
  .lesson-sidebar-toggle,
  .lesson-sidebar-overlay {
    display: none;
  }
}