/* CSS Variables for Theme Management */
:root {
  /* Dark Theme (Default) */
  --bg-primary: #0a0b0f;
  --bg-secondary: #1a1d29;
  --bg-tertiary: #242837;
  --text-primary: #ffffff;
  --text-secondary: #b8bcc8;
  --text-muted: #7c8394;
  --accent-primary: #6366f1;
  --accent-secondary: #8b5cf6;
  --accent-success: #10b981;
  --accent-warning: #f59e0b;
  --accent-error: #ef4444;
  --border-color: #2d3748;
  --shadow-color: rgba(0, 0, 0, 0.3);
  --gradient-primary: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
  --gradient-secondary: linear-gradient(135deg, #10b981 0%, #059669 100%);
}

/* Light Theme */
[data-theme="light"] {
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-tertiary: #f1f5f9;
  --text-primary: #1e293b;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --accent-primary: #6366f1;
  --accent-secondary: #8b5cf6;
  --accent-success: #10b981;
  --accent-warning: #f59e0b;
  --accent-error: #ef4444;
  --border-color: #e2e8f0;
  --shadow-color: rgba(0, 0, 0, 0.1);
  --gradient-primary: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
  --gradient-secondary: linear-gradient(135deg, #10b981 0%, #059669 100%);
}

/* Reset and Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  transition: all 0.3s ease;
  min-height: 100vh;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header Styles */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 2rem 0;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 3rem;
}

.logo-section {
  flex: 1;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.5rem;
}

.logo i {
  font-size: 2rem;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.logo h1 {
  font-size: 2.5rem;
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.subtitle {
  color: var(--text-secondary);
  font-size: 1.1rem;
  font-weight: 400;
}

/* Theme Toggle */
.theme-toggle {
  position: relative;
  width: 60px;
  height: 30px;
  background: var(--bg-tertiary);
  border: 2px solid var(--border-color);
  border-radius: 25px;
  cursor: pointer;
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 8px;
  overflow: hidden;
}

.theme-toggle:hover {
  transform: scale(1.05);
  border-color: var(--accent-primary);
}

.theme-toggle i {
  font-size: 0.8rem;
  transition: all 0.3s ease;
  z-index: 2;
}

.theme-toggle .fa-sun {
  color: var(--accent-warning);
  opacity: 0.5;
}

.theme-toggle .fa-moon {
  color: var(--accent-primary);
  opacity: 1;
}

[data-theme="light"] .theme-toggle .fa-sun {
  opacity: 1;
}

[data-theme="light"] .theme-toggle .fa-moon {
  opacity: 0.5;
}

.theme-toggle::before {
  content: '';
  position: absolute;
  top: 2px;
  left: 2px;
  width: 24px;
  height: 24px;
  background: var(--gradient-primary);
  border-radius: 50%;
  transition: transform 0.3s ease;
  z-index: 1;
}

[data-theme="light"] .theme-toggle::before {
  transform: translateX(28px);
}

/* Main Content */
.main-content {
  flex: 1;
  padding-bottom: 2rem;
}

/* Systems Grid */
.systems-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: 1.5rem;
  margin-bottom: 3rem;
}

/* System Cards */
.system-card {
  display: flex;
  align-items: center;
  padding: 1.5rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  text-decoration: none;
  color: inherit;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
  opacity: 0;
  transform: translateY(20px);
}

.system-card.animate-in {
  animation: slideInUp 0.6s ease forwards;
}

@keyframes slideInUp {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.system-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity 0.3s ease;
  z-index: 0;
}

.system-card:hover::before {
  opacity: 0.05;
}

.system-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 20px 40px var(--shadow-color);
  border-color: var(--accent-primary);
}

.system-card:hover .card-arrow {
  transform: translateX(8px);
  color: var(--accent-primary);
}

.system-card:hover .card-icon {
  transform: scale(1.1);
}

.system-card > * {
  position: relative;
  z-index: 1;
}

/* Card Icon */
.card-icon {
  width: 60px;
  height: 60px;
  background: var(--bg-tertiary);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-right: 1rem;
  transition: all 0.3s ease;
  border: 1px solid var(--border-color);
}

.card-icon i {
  font-size: 1.5rem;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Card Content */
.card-content {
  flex: 1;
}

.card-content h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
  color: var(--text-primary);
}

.card-content p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  font-weight: 400;
}

/* Card Arrow */
.card-arrow {
  margin-left: 1rem;
  color: var(--text-muted);
  transition: all 0.3s ease;
}

.card-arrow i {
  font-size: 1.1rem;
}

/* Footer */
.footer {
  text-align: center;
  padding: 2rem 0;
  border-top: 1px solid var(--border-color);
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 768px) {
  .container {
    padding: 0 15px;
  }
  
  .header {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
    padding: 1.5rem 0;
  }
  
  .logo h1 {
    font-size: 2rem;
  }
  
  .systems-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
  
  .system-card {
    padding: 1.25rem;
  }
  
  .card-content h3 {
    font-size: 1.1rem;
  }
  
  .card-content p {
    font-size: 0.85rem;
  }
}

@media (max-width: 480px) {
  .logo h1 {
    font-size: 1.75rem;
  }
  
  .subtitle {
    font-size: 1rem;
  }
  
  .system-card {
    padding: 1rem;
  }
  
  .card-icon {
    width: 50px;
    height: 50px;
  }
  
  .card-icon i {
    font-size: 1.25rem;
  }
}

/* Additional Animations */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* Focus States for Accessibility */
.system-card:focus {
  outline: 2px solid var(--accent-primary);
  outline-offset: 2px;
}

.theme-toggle:focus {
  outline: 2px solid var(--accent-primary);
  outline-offset: 2px;
}

/* High Contrast Mode Support */
@media (prefers-contrast: high) {
  .system-card {
    border-width: 2px;
  }
  
  .card-icon {
    border-width: 2px;
  }
}

/* Print Styles */
@media print {
  .theme-toggle {
    display: none;
  }
  
  .system-card {
    break-inside: avoid;
    box-shadow: none;
    border: 1px solid #000;
  }
}