/* Base Styles */
:root {
    --color-primary: #2563eb;
    --color-primary-dark: #1d4ed8;
    --color-secondary: #e5e7eb;
    --color-text: #1f2937;
    --color-text-light: #6b7280;
    --color-background: #ffffff;
    --color-accent: #f59e0b;
    --color-accent-dark: #d97706;
    --color-success: #10b981;
    --color-error: #ef4444;
    --color-border: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --border-radius: 8px;
    --transition-speed: 0.3s;
  }
  
  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    line-height: 1.5;
    color: var(--color-text);
    background-color: #f9fafb;
  }
  
  h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 1rem;
  }
  
  h1 {
    font-size: 2rem;
    letter-spacing: -0.025em;
  }
  
  h2 {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    position: relative;
    padding-bottom: 0.5rem;
  }
  
  h2::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: 0;
    width: 50px;
    height: 3px;
    background-color: var(--color-accent);
    border-radius: 3px;
  }
  
  h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
  }
  
  p {
    margin-bottom: 1rem;
  }
  
  img {
    max-width: 100%;
    display: block;
  }
  
  .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
  }
  
  /* Course Header */
  .course-header {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    margin: 2rem 0;
    padding: 2rem;
    background-color: var(--color-background);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
  }
  
  .course-thumbnail {
    width: 100%;
    overflow: hidden;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
  }
  
  .course-thumbnail img {
    width: 100%;
    height: auto;
    object-fit: cover;
    transition: transform var(--transition-speed);
  }
  
  .course-thumbnail img:hover {
    transform: scale(1.03);
  }
  
  .course-info {
    display: flex;
    flex-direction: column;
    gap: 1rem;
  }
  
  .course-meta {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    align-items: flex-start;
  }
  
  .price-container {
    display: flex;
    align-items: center;
    gap: 1rem;
  }
  
  .price {
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-text);
  }
  
  .price.discounted {
    color: var(--color-success);
    animation: fadeIn 0.5s ease-in-out;
  }
  
  .action-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    width: 100%;
  }
  
  /* Buttons */
  .btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 500;
    border-radius: var(--border-radius);
    border: none;
    cursor: pointer;
    transition: all var(--transition-speed);
    text-align: center;
  }
  
  .btn-primary {
    background-color: var(--color-primary);
    color: white;
  }
  
  .btn-primary:hover {
    background-color: var(--color-primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
  }
  
  .btn-primary:active {
    transform: translateY(0);
    box-shadow: var(--shadow-sm);
  }
  
  .btn-secondary {
    background-color: var(--color-secondary);
    color: var(--color-text);
  }
  
  .btn-secondary:hover {
    background-color: #d1d5db;
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
  }
  
  .btn-secondary:active {
    transform: translateY(0);
  }
  
  /* Content Sections */
  .content-wrapper {
    display: flex;
    flex-direction: column;
    gap: 3rem;
    margin-bottom: 3rem;
  }
  
  section {
    padding: 2rem;
    background-color: var(--color-background);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
  }
  
  /* What You Learn Section */
  .learning-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  
  .learning-item {
    display: flex;
    gap: 1rem;
    padding: 1.5rem;
    background-color: #f9fafb;
    border-radius: var(--border-radius);
    transition: transform var(--transition-speed), box-shadow var(--transition-speed);
  }
  
  .learning-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
  }
  
  .learning-icon {
    font-size: 2rem;
    color: var(--color-accent);
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: rgba(245, 158, 11, 0.1);
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    flex-shrink: 0;
  }
  
  .learning-content {
    flex: 1;
  }
  
  .learning-content h3 {
    color: var(--color-text);
    margin-bottom: 0.5rem;
  }
  
  .learning-content p {
    color: var(--color-text-light);
    margin-bottom: 0;
  }
  
  /* About Mentor Section */
  .mentor-profile {
    display: flex;
    flex-direction: column;
    gap: 2rem;
  }
  
  .mentor-image {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    border: 3px solid var(--color-accent);
  }
  
  .mentor-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
  }
  
  .mentor-details {
    flex: 1;
  }
  
  .mentor-title {
    font-size: 1.1rem;
    color: var(--color-accent);
    margin-bottom: 1rem;
    font-weight: 500;
  }
  
  .mentor-bio {
    margin-bottom: 1.5rem;
  }
  
  .social-links {
    display: flex;
    gap: 1rem;
  }
  
  .social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background-color: #f3f4f6;
    color: var(--color-text);
    transition: all var(--transition-speed);
  }
  
  .social-icon {
    width: 20px;
    height: 20px;
  }
  
  .social-link:hover {
    background-color: var(--color-primary);
    color: white;
    transform: translateY(-3px);
    box-shadow: var(--shadow-sm);
  }
  
  /* Modal */
  .modal {
    display: none;
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: var(--color-background);
    padding: 2rem;
    border-radius: var(--border-radius);
    z-index: 1000;
    max-width: 90%;
    width: 450px;
    box-shadow: var(--shadow-lg);
  }
  
  .modal.active {
    display: block;
    animation: fadeInScale 0.3s ease-out;
  }
  
  .modal-content {
    position: relative;
  }
  
  .close-modal {
    position: absolute;
    top: -1rem;
    right: -1rem;
    font-size: 1.5rem;
    cursor: pointer;
    transition: color var(--transition-speed);
  }
  
  .close-modal:hover {
    color: var(--color-error);
  }
  
  .coupon-form {
    display: flex;
    gap: 0.5rem;
    margin: 1.5rem 0;
  }
  
  .coupon-form input {
    flex: 1;
    padding: 0.75rem 1rem;
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    font-size: 1rem;
    outline: none;
    transition: border-color var(--transition-speed), box-shadow var(--transition-speed);
  }
  
  .coupon-form input:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.2);
  }
  
  #coupon-message {
    padding: 0.75rem;
    border-radius: var(--border-radius);
    font-weight: 500;
    margin-top: 1rem;
  }
  
  #coupon-message.success {
    background-color: rgba(16, 185, 129, 0.1);
    color: var(--color-success);
    border: 1px solid rgba(16, 185, 129, 0.2);
  }
  
  #coupon-message.error {
    background-color: rgba(239, 68, 68, 0.1);
    color: var(--color-error);
    border: 1px solid rgba(239, 68, 68, 0.2);
  }
  
  .overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 999;
    backdrop-filter: blur(3px);
  }
  
  /* Helper Classes */
  .hidden {
    display: none;
  }
  
  /* Animations */
  @keyframes fadeIn {
    from {
      opacity: 0;
    }
    to {
      opacity: 1;
    }
  }
  
  @keyframes fadeInScale {
    from {
      opacity: 0;
      transform: translate(-50%, -50%) scale(0.95);
    }
    to {
      opacity: 1;
      transform: translate(-50%, -50%) scale(1);
    }
  }
  
  /* Responsive Styles */
  @media (min-width: 640px) {
    h1 {
      font-size: 2.25rem;
    }
    
    .learning-grid {
      grid-template-columns: repeat(2, 1fr);
    }
    
    .course-meta {
      flex-direction: row;
      justify-content: space-between;
      align-items: center;
    }
  }
  
  @media (min-width: 768px) {
    .course-header {
      flex-direction: row;
      align-items: flex-start;
    }
    
    .course-thumbnail {
      width: 40%;
      flex-shrink: 0;
    }
    
    .course-info {
      flex: 1;
    }
    
    .mentor-profile {
      flex-direction: row;
      align-items: center;
    }
  }
  
  @media (min-width: 1024px) {
    .learning-grid {
      grid-template-columns: repeat(2, 1fr);
    }
    
    h1 {
      font-size: 2.5rem;
    }
    
    .container {
      padding: 0 2rem;
    }
  }