/* ============================================
   LIIT Platform - Main Stylesheet
   Loveworld Institute of Innovation and Technology
   ============================================ */

/* CSS Variables */
:root {
  --primary-color: #1a56db;
  --primary-dark: #1e40af;
  --primary-light: #3b82f6;
  --secondary-color: #0891b2;
  --accent-color: #f59e0b;
  --success-color: #10b981;
  --warning-color: #f59e0b;
  --danger-color: #ef4444;
  --dark-color: #1f2937;
  --gray-900: #111827;
  --gray-800: #1f2937;
  --gray-700: #374151;
  --gray-600: #4b5563;
  --gray-500: #6b7280;
  --gray-400: #9ca3af;
  --gray-300: #d1d5db;
  --gray-200: #e5e7eb;
  --gray-100: #f3f4f6;
  --gray-50: #f9fafb;
  --white: #ffffff;
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
  --radius-sm: 0.25rem;
  --radius: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --transition: all 0.3s ease;
}

/* Reset & Base */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-family);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--gray-800);
  background-color: var(--white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

ul, ol {
  list-style: none;
}

button, input, select, textarea {
  font-family: inherit;
  font-size: inherit;
}

/* Container */
.container {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.container-sm {
  max-width: 768px;
}

.container-lg {
  max-width: 1536px;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  color: var(--gray-900);
}

h1 { font-size: 3rem; }
h2 { font-size: 2.25rem; }
h3 { font-size: 1.875rem; }
h4 { font-size: 1.5rem; }
h5 { font-size: 1.25rem; }
h6 { font-size: 1rem; }

p {
  margin-bottom: 1rem;
  color: var(--gray-600);
}

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

.text-primary { color: var(--primary-color); }
.text-secondary { color: var(--secondary-color); }
.text-accent { color: var(--accent-color); }
.text-success { color: var(--success-color); }
.text-warning { color: var(--warning-color); }
.text-danger { color: var(--danger-color); }
.text-muted { color: var(--gray-500); }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius);
  border: 2px solid transparent;
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

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

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

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

.btn-secondary:hover {
  background-color: #0e7490;
  transform: translateY(-2px);
}

.btn-outline {
  background-color: transparent;
  border-color: var(--primary-color);
  color: var(--primary-color);
}

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

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

.btn-white:hover {
  background-color: var(--gray-100);
}

.btn-lg {
  padding: 1rem 2rem;
  font-size: 1.125rem;
}

.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

.btn-icon {
  width: 2.5rem;
  height: 2.5rem;
  padding: 0;
  border-radius: 50%;
}

/* Cards */
.card {
  background-color: var(--white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: var(--transition);
}

.card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}

.card-img {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.card-body {
  padding: 1.5rem;
}

.card-title {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
}

.card-text {
  color: var(--gray-600);
  margin-bottom: 1rem;
}

/* Navigation */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-sm);
  padding: 1rem 0;
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.navbar-brand img {
  height: 40px;
  width: auto;
}

.navbar-brand span {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--primary-color);
}

.navbar-nav {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-link {
  font-weight: 500;
  color: var(--gray-700);
  padding: 0.5rem 0;
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--primary-color);
  transition: var(--transition);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-link:hover {
  color: var(--primary-color);
}

.navbar-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.mobile-menu-btn span {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--gray-700);
  margin: 6px 0;
  transition: var(--transition);
}

/* Hero Section */
.hero {
  padding: 8rem 0 5rem;
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: 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='0.05'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

.hero .container {
  position: relative;
  z-index: 1;
}

.hero-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
}

.hero-text {
  color: var(--white);
}

.hero-text h1 {
  font-size: 3.5rem;
  color: var(--white);
  margin-bottom: 1.5rem;
  line-height: 1.1;
}

.hero-text p {
  font-size: 1.25rem;
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: 2rem;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.hero-image {
  position: relative;
}

.hero-image img {
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
}

.hero-stats {
  display: flex;
  gap: 3rem;
  margin-top: 3rem;
}

.stat-item {
  text-align: center;
  color: var(--white);
}

.stat-number {
  font-size: 2.5rem;
  font-weight: 800;
  display: block;
}

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

/* Sections */
.section {
  padding: 5rem 0;
}

.section-header {
  text-align: center;
  max-width: 700px;
  margin: 0 auto 3rem;
}

.section-header h2 {
  margin-bottom: 1rem;
}

.section-header p {
  font-size: 1.125rem;
}

.section-bg {
  background-color: var(--gray-50);
}

/* Features */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.feature-card {
  text-align: center;
  padding: 2rem;
}

.feature-icon {
  width: 80px;
  height: 80px;
  margin: 0 auto 1.5rem;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--white);
  font-size: 2rem;
}

.feature-card h4 {
  margin-bottom: 0.75rem;
}

/* Courses Grid */
.courses-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.course-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: var(--transition);
}

.course-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-xl);
}

.course-img {
  position: relative;
  height: 200px;
  overflow: hidden;
}

.course-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: var(--transition);
}

.course-card:hover .course-img img {
  transform: scale(1.1);
}

.course-badge {
  position: absolute;
  top: 1rem;
  left: 1rem;
  background-color: var(--accent-color);
  color: var(--white);
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
}

.course-content {
  padding: 1.5rem;
}

.course-category {
  font-size: 0.75rem;
  color: var(--primary-color);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 0.5rem;
}

.course-title {
  font-size: 1.125rem;
  margin-bottom: 0.75rem;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.course-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 0.875rem;
  color: var(--gray-500);
  margin-bottom: 1rem;
}

.course-meta span {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.course-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 1rem;
  border-top: 1px solid var(--gray-200);
}

.course-price {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--primary-color);
}

.course-price span {
  font-size: 0.875rem;
  color: var(--gray-400);
  text-decoration: line-through;
  margin-left: 0.5rem;
}

.course-rating {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  color: var(--accent-color);
}

.course-rating span {
  color: var(--gray-600);
  margin-left: 0.25rem;
}

/* Testimonials */
.testimonials-slider {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.testimonial-card {
  background: var(--white);
  padding: 2rem;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  position: relative;
}

.testimonial-card::before {
  content: '"';
  position: absolute;
  top: 1rem;
  right: 1.5rem;
  font-size: 4rem;
  color: var(--primary-color);
  opacity: 0.1;
  font-family: Georgia, serif;
  line-height: 1;
}

.testimonial-text {
  font-style: italic;
  margin-bottom: 1.5rem;
  color: var(--gray-600);
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.testimonial-avatar {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  object-fit: cover;
}

.testimonial-info h5 {
  font-size: 1rem;
  margin-bottom: 0.125rem;
}

.testimonial-info span {
  font-size: 0.875rem;
  color: var(--gray-500);
}

/* CTA Section */
.cta-section {
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--secondary-color) 100%);
  padding: 5rem 0;
  text-align: center;
  color: var(--white);
}

.cta-section h2 {
  color: var(--white);
  margin-bottom: 1rem;
}

.cta-section p {
  color: rgba(255, 255, 255, 0.9);
  font-size: 1.25rem;
  margin-bottom: 2rem;
}

/* Footer */
.footer {
  background-color: var(--gray-900);
  color: var(--gray-400);
  padding: 5rem 0 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-brand img {
  height: 50px;
  margin-bottom: 1rem;
}

.footer-brand p {
  color: var(--gray-400);
  margin-bottom: 1.5rem;
}

.footer-social {
  display: flex;
  gap: 1rem;
}

.footer-social a {
  width: 40px;
  height: 40px;
  background-color: var(--gray-800);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gray-400);
  transition: var(--transition);
}

.footer-social a:hover {
  background-color: var(--primary-color);
  color: var(--white);
}

.footer-title {
  color: var(--white);
  font-size: 1.125rem;
  margin-bottom: 1.5rem;
}

.footer-links li {
  margin-bottom: 0.75rem;
}

.footer-links a:hover {
  color: var(--primary-color);
}

.footer-bottom {
  border-top: 1px solid var(--gray-800);
  padding: 1.5rem 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

/* Forms */
.form-group {
  margin-bottom: 1.5rem;
}

.form-label {
  display: block;
  font-weight: 500;
  margin-bottom: 0.5rem;
  color: var(--gray-700);
}

.form-control {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius);
  font-size: 1rem;
  transition: var(--transition);
}

.form-control:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(26, 86, 219, 0.1);
}

.form-control::placeholder {
  color: var(--gray-400);
}

textarea.form-control {
  min-height: 120px;
  resize: vertical;
}

/* Alerts */
.alert {
  padding: 1rem 1.5rem;
  border-radius: var(--radius);
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.alert-success {
  background-color: #d1fae5;
  color: #065f46;
}

.alert-danger {
  background-color: #fee2e2;
  color: #991b1b;
}

.alert-warning {
  background-color: #fef3c7;
  color: #92400e;
}

.alert-info {
  background-color: #dbeafe;
  color: #1e40af;
}

/* Badges */
.badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: var(--radius);
  text-transform: uppercase;
}

.badge-primary {
  background-color: var(--primary-color);
  color: var(--white);
}

.badge-success {
  background-color: var(--success-color);
  color: var(--white);
}

.badge-warning {
  background-color: var(--warning-color);
  color: var(--white);
}

.badge-danger {
  background-color: var(--danger-color);
  color: var(--white);
}

/* Utilities */
.mt-1 { margin-top: 0.25rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-3 { margin-top: 1rem; }
.mt-4 { margin-top: 1.5rem; }
.mt-5 { margin-top: 3rem; }

.mb-1 { margin-bottom: 0.25rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-3 { margin-bottom: 1rem; }
.mb-4 { margin-bottom: 1.5rem; }
.mb-5 { margin-bottom: 3rem; }

.py-1 { padding-top: 0.25rem; padding-bottom: 0.25rem; }
.py-2 { padding-top: 0.5rem; padding-bottom: 0.5rem; }
.py-3 { padding-top: 1rem; padding-bottom: 1rem; }
.py-4 { padding-top: 1.5rem; padding-bottom: 1.5rem; }
.py-5 { padding-top: 3rem; padding-bottom: 3rem; }

.d-flex { display: flex; }
.align-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: 0.25rem; }
.gap-2 { gap: 0.5rem; }
.gap-3 { gap: 1rem; }
.gap-4 { gap: 1.5rem; }

/* Responsive */
@media (max-width: 1024px) {
  .hero-content {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-text h1 {
    font-size: 2.5rem;
  }

  .hero-buttons {
    justify-content: center;
  }

  .hero-stats {
    justify-content: center;
  }

  .hero-image {
    order: -1;
    max-width: 500px;
    margin: 0 auto;
  }

  .features-grid,
  .courses-grid,
  .testimonials-slider {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  h1 { font-size: 2rem; }
  h2 { font-size: 1.75rem; }

  .navbar-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--white);
    flex-direction: column;
    padding: 1rem;
    box-shadow: var(--shadow-lg);
  }

  .navbar-nav.active {
    display: flex;
  }

  .mobile-menu-btn {
    display: block;
  }

  .hero {
    padding: 6rem 0 3rem;
  }

  .hero-text h1 {
    font-size: 2rem;
  }

  .hero-stats {
    flex-direction: column;
    gap: 1.5rem;
  }

  .features-grid,
  .courses-grid,
  .testimonials-slider {
    grid-template-columns: 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }
}

/* Animations */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in {
  animation: fadeIn 0.6s ease forwards;
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateX(-30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.slide-in {
  animation: slideIn 0.6s ease forwards;
}

/* Loading Spinner */
.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--gray-200);
  border-top-color: var(--primary-color);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* Modal */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2000;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal {
  background-color: var(--white);
  border-radius: var(--radius-lg);
  max-width: 500px;
  width: 90%;
  max-height: 90vh;
  overflow-y: auto;
  transform: scale(0.9);
  transition: var(--transition);
}

.modal-overlay.active .modal {
  transform: scale(1);
}

.modal-header {
  padding: 1.5rem;
  border-bottom: 1px solid var(--gray-200);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.modal-body {
  padding: 1.5rem;
}

.modal-footer {
  padding: 1.5rem;
  border-top: 1px solid var(--gray-200);
  display: flex;
  justify-content: flex-end;
  gap: 1rem;
}