:root {
  /* Colors */
  --primary-50: #eef2ff;
  --primary-100: #e0e7ff;
  --primary-500: #6366f1;
  --primary-600: #4f46e5;
  --primary-700: #4338ca;

  --purple-500: #a855f7;
  --purple-600: #9333ea;

  --emerald-500: #10b981;
  --emerald-600: #059669;

  --amber-500: #f59e0b;
  --amber-600: #d97706;

  --yellow-300: #fcd34d;
  --yellow-400: #fbbf24;

  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-800: #1f2937;
  --gray-900: #111827;

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;
  --text-6xl: 3.75rem;
  --text-7xl: 4.5rem;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1);
  --shadow-2xl: 0 25px 50px -12px rgb(0 0 0 / 0.25);

  /* Border Radius */
  --radius-lg: 0.5rem;
  --radius-xl: 0.75rem;
  --radius-2xl: 1rem;
  --radius-3xl: 1.5rem;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 300ms ease;
  --transition-slow: 500ms ease;
}



@media (min-width: 640px) {
  .container {
    padding: 0 var(--space-6);
  }
}

@media (min-width: 1024px) {
  .container {
    padding: 0 var(--space-8);
  }
}

/* Navigation */


/* Page Header */
.page-header {
  background: linear-gradient(135deg, var(--primary-600), var(--purple-600));
  padding: var(--space-24) 0;
  position: relative;
  overflow: hidden;
}

.page-header::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.1'%3E%3Ccircle cx='30' cy='30' r='4'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
  opacity: 0.3;
}

.page-header-content {
  position: relative;
  text-align: center;
  color: white;
}

.page-title {
  font-size: var(--text-5xl);
  font-weight: 700;
  margin-bottom: var(--space-6);
  animation: fadeInUp 0.8s ease-out;
}

@media (min-width: 768px) {
  .page-title {
    font-size: var(--text-6xl);
  }
}

.page-subtitle {
  font-size: var(--text-xl);
  color: rgba(255, 255, 255, 0.9);
  max-width: 48rem;
  margin: 0 auto;
  line-height: 1.75;
  animation: fadeInUp 0.8s ease-out 0.2s both;
}

/* Courses Section */
/* .courses-section {
  padding: var(--space-24) 0;
  background: white;
} */

.courses-header {
  text-align: center;
  margin-bottom: var(--space-12);
}

.filter-controls {
  display: flex;
  justify-content: center;
  gap: var(--space-4);
  flex-wrap: wrap;
  margin-bottom: var(--space-12);
}

.filter-btn {
  background: var(--gray-100);
  border: none;
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-xl);
  font-weight: 500;
  color: var(--gray-700);
  cursor: pointer;
  transition: all var(--transition-normal);
}

.filter-btn:hover,
.filter-btn.active {
  background: var(--primary-600);
  color: white;
}

.courses-grid {
  display: grid;
  gap: var(--space-8);
}

@media (min-width: 768px) {
  .courses-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .courses-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.course-card {
  background: white;
  border-radius: var(--radius-3xl);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-slow);
  position: relative;
}

.course-card:hover {
  box-shadow: var(--shadow-xl);
  transform: translateY(-0.5rem);
}

.course-image {
  height: 180px;
  background: linear-gradient(135deg, var(--primary-500), var(--purple-600));
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 3rem;
}

.course-content {
  padding: var(--space-6);
}

.course-category {
  display: inline-block;
  background: var(--primary-100);
  color: var(--primary-700);
  font-size: var(--text-sm);
  font-weight: 600;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-4);
}

.course-title {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: var(--space-4);
}

.course-description {
  color: var(--gray-600);
  font-size: var(--text-base);
  line-height: 1.6;
  margin-bottom: var(--space-6);
}

.course-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--gray-500);
  font-size: var(--text-sm);
}

.course-meta i {
  margin-right: var(--space-1);
}

/* Animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(2rem);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-fade-in-up {
  animation: fadeInUp 0.6s ease-out;
}