.curriculum_section {
    margin-top: 30px;
    padding: 20px 0;
    background: #f8f9fa;
    min-height: calc(100vh - 100px);
  }
  
  .lesson-sidebar {
    background: white;
    border-right: 1px solid #e0e0e0;
    padding: 20px;
    height: calc(100vh - 100px);
    position: sticky;
    top: 0;
  }
  
  .course-outline h3 {
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 2px solid #D6CFAF;
  }
  
  .lesson-list {
    list-style: none;
    padding: 0;
  }
  
  .lesson-list li {
    padding: 15px;
    margin: 5px 0;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
  }
  
  .lesson-list li:hover {
    background: #f0f0f0;
  }
  
  .lesson-list li.active {
    background: #D6CFAF;
    color: #000000;
  }
  
  .lesson-number {
    width: 24px;
    height: 24px;
    background: #D6CFAF;
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin-right: 10px;
    font-size: 14px;
  }
  
  .active .lesson-number {
    background: #644d1b;
    color: #ffffff;
  }
  
  .main-content {
    padding: 30px;
  }
  
  .video-container {
    background: white;
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
  }
  
  .video-wrapper {
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    margin: 20px 0;
  }
  
  .video-wrapper iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 75%;
    height: 80%;
    border-radius: 8px;
  }
  
  .video-description {
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid #e0e0e0;
  }
  
  @media (max-width: 768px) {
    .lesson-sidebar {
      height: auto;
      position: relative;
      margin-top: 0;
    }
    
    .main-content {
      padding: 15px;
    }
  }

  .quiz-form {
    background: #ffffff;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.quiz-question {
    margin-bottom: 20px;
}

.form-check {
    margin: 10px 0;
}

.btn-primary {
    background-color: #D6CFAF;
    border: none;
    padding: 10px 20px;
    color: #000000;
    transition: all 0.3s ease;
}

.btn-primary:hover {
    background-color: #000000;
    color: #D6CFAF;
}

.under-development-overlay {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(255,255,255,0.96);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 10;
  text-align: center;
  border-radius: 12px;
  box-shadow: 0 2px 16px rgba(0,0,0,0.07);
  padding: 32px 16px;
}
.under-development-overlay h2 {
  color: #36454F;
  margin-bottom: 8px;
  font-size: 1.5rem;
  font-weight: 700;
}
.under-development-overlay p {
  color: #555;
  font-size: 1rem;
  margin: 0;
}

.lesson-list li.active {
  background: #f2ebc7;
  font-weight: bold;
  border-left: 4px solid #644d1b;
} 

.lesson-sidebar {
  height: calc(100vh - 100px);
  position: sticky;
  top: 20px;
}

.course-outline {
  height: 100%;
  overflow-y: auto;
  padding-right: 10px;
}

/* Customize scrollbar */
.course-outline::-webkit-scrollbar {
  width: 8px;
}

.course-outline::-webkit-scrollbar-track {
  background: #f1f1f1;
  border-radius: 4px;
}

.course-outline::-webkit-scrollbar-thumb {
  background: #888;
  border-radius: 4px;
}

.course-outline::-webkit-scrollbar-thumb:hover {
  background: #555;
}