/* ============================================
   Python to AI Agents - Custom Styles
   ============================================ */

:root {
  --primary-color: #3b82f6;
  --primary-dark: #2563eb;
  --primary-light: #60a5fa;
  --success-color: #10b981;
  --warning-color: #f59e0b;
  --danger-color: #ef4444;
  --text-dark: #1f2937;
  --text-light: #6b7280;
  --bg-light: #f9fafb;
  --bg-card: #ffffff;
  --border-color: #e5e7eb;
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

/* ============================================
   Hero Section
   ============================================ */

.hero-section {
  text-align: center;
  padding: 3rem 2rem;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  border-radius: 1rem;
  margin: 2rem 0 3rem;
  box-shadow: var(--shadow-lg);
}

.hero-title {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 1rem;
  line-height: 1.2;
}

.hero-subtitle {
  font-size: 1.25rem;
  opacity: 0.95;
  margin-bottom: 2rem;
}

/* ============================================
   Buttons & CTAs
   ============================================ */

.cta-buttons {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  margin: 2rem 0;
}

.btn-primary,
.btn-secondary {
  display: inline-block;
  padding: 0.875rem 2rem;
  border-radius: 0.5rem;
  text-decoration: none;
  font-weight: 600;
  transition: all 0.3s ease;
  font-size: 1rem;
}

.btn-primary {
  background: var(--primary-color);
  color: white;
  box-shadow: var(--shadow);
}

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-secondary {
  background: white;
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
}

.btn-secondary:hover {
  background: var(--primary-color);
  color: white;
}

.btn-primary.large {
  padding: 1.25rem 3rem;
  font-size: 1.125rem;
}

/* ============================================
   Feature Grid
   ============================================ */

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}

.feature-card {
  background: var(--bg-card);
  padding: 2rem;
  border-radius: 1rem;
  border: 1px solid var(--border-color);
  text-align: center;
  transition: all 0.3s ease;
  box-shadow: var(--shadow);
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-color);
}

.feature-icon {
  font-size: 3rem;
  margin-bottom: 1rem;
}

.feature-card h3 {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
  color: var(--text-dark);
}

.feature-card p {
  color: var(--text-light);
  line-height: 1.6;
}

/* ============================================
   Journey Timeline
   ============================================ */

.journey-timeline {
  margin: 2rem 0;
}

.journey-timeline > div {
  background: var(--bg-card);
  padding: 2rem;
  border-radius: 1rem;
  border-left: 4px solid var(--primary-color);
  margin-bottom: 2rem;
  box-shadow: var(--shadow);
}

.journey-timeline h3 {
  margin-top: 0;
  color: var(--primary-color);
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* ============================================
   Stage Badges
   ============================================ */

.stage-badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  border-radius: 9999px;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.stage-beginner {
  background: #dcfce7;
  color: #166534;
}

.stage-intermediate {
  background: #dbeafe;
  color: #1e40af;
}

.stage-advanced {
  background: #fef3c7;
  color: #92400e;
}

.stage-expert {
  background: #fce7f3;
  color: #9f1239;
}

/* ============================================
   Stats Grid
   ============================================ */

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}

.stat-card {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: white;
  padding: 2rem;
  border-radius: 1rem;
  text-align: center;
  box-shadow: var(--shadow-lg);
}

.stat-number {
  font-size: 3rem;
  font-weight: 700;
  line-height: 1;
}

.stat-label {
  font-size: 0.875rem;
  opacity: 0.9;
  margin-top: 0.5rem;
}

/* ============================================
   Audience Section
   ============================================ */

.audience-section {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin: 2rem 0;
}

.audience-section > div {
  background: var(--bg-card);
  padding: 2rem;
  border-radius: 1rem;
  border: 2px solid var(--border-color);
}

.audience-section h3 {
  margin-top: 0;
}

.audience-section ul {
  list-style: none;
  padding: 0;
}

.audience-section li {
  padding: 0.5rem 0;
  padding-left: 1.5rem;
  position: relative;
}

.audience-section li::before {
  position: absolute;
  left: 0;
  font-weight: bold;
}

/* ============================================
   CTA Section
   ============================================ */

.cta-section {
  text-align: center;
  background: var(--bg-light);
  padding: 3rem 2rem;
  border-radius: 1rem;
  margin: 3rem 0;
}

.cta-section h3 {
  font-size: 2rem;
  margin-bottom: 1rem;
}

.cta-footnote {
  margin-top: 1rem;
  color: var(--text-light);
  font-size: 0.875rem;
}

.footer-cta {
  text-align: center;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 4rem 2rem;
  border-radius: 1rem;
  margin: 3rem 0;
}

.footer-cta h2 {
  font-size: 2rem;
  margin-bottom: 2rem;
}

/* ============================================
   Responsive Design
   ============================================ */

@media (max-width: 768px) {
  .hero-title {
    font-size: 1.75rem;
  }
  
  .hero-subtitle {
    font-size: 1rem;
  }
  
  .feature-grid {
    grid-template-columns: 1fr;
  }
  
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .audience-section {
    grid-template-columns: 1fr;
  }
  
  .cta-buttons {
    flex-direction: column;
  }
  
  .btn-primary,
  .btn-secondary {
    width: 100%;
    text-align: center;
  }
}

/* ============================================
   Sidebar Improvements
   ============================================ */

.sidebar-nav li {
  position: relative;
}

.sidebar-nav strong {
  display: block;
  padding: 0.5rem 0;
  color: var(--text-dark);
  font-weight: 600;
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-top: 1rem;
}

/* ============================================
   Cover Page Improvements
   ============================================ */

section.cover {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

section.cover h1 {
  font-size: 3rem;
  font-weight: 700;
}

section.cover .cover-main > p:last-child a {
  background: white;
  color: var(--primary-color);
  border: none;
  font-weight: 600;
  padding: 1rem 2.5rem;
  border-radius: 0.5rem;
  transition: all 0.3s ease;
}

section.cover .cover-main > p:last-child a:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

/* ============================================
   Typography Improvements
   ============================================ */

.markdown-section {
  max-width: 900px;
  font-size: 16px;
  line-height: 1.7;
}

.markdown-section h1 {
  font-size: 2.5rem;
  font-weight: 700;
  margin-top: 2rem;
  color: var(--text-dark);
}

.markdown-section h2 {
  font-size: 2rem;
  font-weight: 600;
  margin-top: 3rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--border-color);
}

.markdown-section h3 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-top: 2rem;
}

/* ============================================
   Code Blocks
   ============================================ */

.markdown-section pre {
  border-radius: 0.5rem;
  box-shadow: var(--shadow);
}

.markdown-section code {
  border-radius: 0.25rem;
  padding: 0.125rem 0.375rem;
  font-size: 0.875em;
}

/* ============================================
   Alerts / Callouts
   ============================================ */

.markdown-section blockquote {
  border-left: 4px solid var(--primary-color);
  background: var(--bg-light);
  padding: 1rem 1.5rem;
  border-radius: 0.5rem;
  margin: 2rem 0;
}

/* ============================================
   Utility Classes
   ============================================ */

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

.mt-4 {
  margin-top: 2rem;
}

.mb-4 {
  margin-bottom: 2rem;
}