:root {
  /* Modern Typography */
  --font-family-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-family-heading: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  
  /* Refined Color Palette */
  --primary-blue: #0066FF;
  --primary-green: #00D4AA;
  --primary-red: #FF6B6B;
  --primary-purple: #8B5CF6;
  
  /* Neutral Colors */
  --neutral-50: #F8FAFC;
  --neutral-100: #F1F5F9;
  --neutral-200: #E2E8F0;
  --neutral-300: #CBD5E1;
  --neutral-400: #94A3B8;
  --neutral-500: #64748B;
  --neutral-600: #475569;
  --neutral-700: #334155;
  --neutral-800: #1E293B;
  --neutral-900: #0F172A;
  
  /* Semantic Colors */
  --success: #10B981;
  --success-light: #D1FAE5;
  --warning: #F59E0B;
  --warning-light: #FEF3C7;
  --error: #EF4444;
  --error-light: #FEE2E2;
  --info: #3B82F6;
  --info-light: #DBEAFE;
  
  /* Background Colors */
  --background-primary: #F8FAFC;
  --background-secondary: #FFFFFF;
  --background-tertiary: #F1F5F9;
  
  /* Text Colors */
  --text-primary: #0F172A;
  --text-secondary: #64748B;
  --text-tertiary: #94A3B8;
  --text-inverse: #FFFFFF;
  
  /* Surface Colors */
  --surface-primary: #FFFFFF;
  --surface-secondary: #F8FAFC;
  --surface-elevated: #FFFFFF;
  
  /* Border Colors */
  --border-light: #E2E8F0;
  --border-medium: #CBD5E1;
  --border-strong: #94A3B8;
  
  /* Shadow System */
  --shadow-xs: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
  --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);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  
  /* Spacing System */
  --space-1: 0.25rem;   /* 4px */
  --space-2: 0.5rem;    /* 8px */
  --space-3: 0.75rem;   /* 12px */
  --space-4: 1rem;      /* 16px */
  --space-5: 1.25rem;   /* 20px */
  --space-6: 1.5rem;    /* 24px */
  --space-8: 2rem;      /* 32px */
  --space-10: 2.5rem;   /* 40px */
  --space-12: 3rem;     /* 48px */
  --space-16: 4rem;     /* 64px */
  --space-20: 5rem;     /* 80px */
  --space-24: 6rem;     /* 96px */
  
  /* Typography Scale */
  --text-xs: 0.75rem;    /* 12px */
  --text-sm: 0.875rem;   /* 14px */
  --text-base: 1rem;     /* 16px */
  --text-lg: 1.125rem;   /* 18px */
  --text-xl: 1.25rem;    /* 20px */
  --text-2xl: 1.5rem;    /* 24px */
  --text-3xl: 1.875rem;  /* 30px */
  --text-4xl: 2.25rem;  /* 36px */
  --text-5xl: 3rem;     /* 48px */
  
  /* Border Radius */
  --radius-sm: 0.25rem;   /* 4px */
  --radius-md: 0.375rem;  /* 6px */
  --radius-lg: 0.5rem;    /* 8px */
  --radius-xl: 0.75rem;   /* 12px */
  --radius-2xl: 1rem;    /* 16px */
  --radius-3xl: 1.5rem;  /* 24px */
  --radius-full: 9999px;
  
  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-normal: 250ms ease-in-out;
  --transition-slow: 350ms ease-in-out;
  
  /* Z-Index Scale */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
  --z-toast: 1080;
}

.menu-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
}

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

.menu-panel {
  position: fixed;
  top: 0;
  right: -300px;
  width: 300px;
  height: 100%;
  background: var(--card-background);
  box-shadow: -5px 0 15px var(--shadow-color);
  z-index: 1001;
  transition: right 0.3s ease;
  padding: 20px;
}

.menu-panel.active {
  right: 0;
}

.menu-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 30px;
}

.menu-logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.menu-logo img {
  width: 32px;
  height: 32px;
  border-radius: 8px;
}

.menu-logo span {
  font-size: 20px;
  font-weight: 600;
  color: var(--text-color);
}

.menu-close {
  background: none;
  border: none;
  font-size: 24px;
  color: var(--text-color);
  cursor: pointer;
  padding: 5px;
}

.menu-items {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.menu-item {
  display: flex;
  align-items: center;
  gap: 15px;
  padding: 12px 15px;
  border-radius: 10px;
  color: var(--text-color);
  text-decoration: none;
  transition: all 0.2s ease;
}

.menu-item:hover {
  background: var(--background-color);
}

.menu-item.active {
  background: var(--primary-color);
  color: white;
}

.menu-item i {
  font-size: 20px;
  width: 24px;
  text-align: center;
}

.menu-item.logout {
  color: var(--danger-color);
  margin-top: auto;
}

.menu-item.logout:hover {
  background: #ffebeb;
}

/* Modern Component Styles */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  border: none;
  border-radius: var(--radius-lg);
  font-family: var(--font-family-sf);
  font-weight: var(--font-weight-medium);
  font-size: var(--text-base);
  line-height: 1.5;
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary-blue) 0%, #0052CC 100%);
  color: var(--text-inverse);
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background: var(--surface-primary);
  color: var(--text-primary);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-xs);
}

.btn-secondary:hover:not(:disabled) {
  background: var(--neutral-50);
  border-color: var(--border-medium);
}

.btn-success {
  background: linear-gradient(135deg, var(--success) 0%, #059669 100%);
  color: var(--text-inverse);
  box-shadow: var(--shadow-sm);
}

.btn-danger {
  background: linear-gradient(135deg, var(--error) 0%, #DC2626 100%);
  color: var(--text-inverse);
  box-shadow: var(--shadow-sm);
}

.btn-ghost {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid transparent;
}

.btn-ghost:hover:not(:disabled) {
  background: var(--neutral-100);
}

/* Card Components */
.card {
  background: var(--surface-primary);
  border-radius: var(--radius-2xl);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-light);
  transition: all var(--transition-normal);
  overflow: hidden;
}

.card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.card-elevated {
  box-shadow: var(--shadow-lg);
}

.card-elevated:hover {
  box-shadow: var(--shadow-xl);
}

.card-header {
  padding: var(--space-6);
  border-bottom: 1px solid var(--border-light);
}

.card-body {
  padding: var(--space-6);
}

.card-footer {
  padding: var(--space-6);
  border-top: 1px solid var(--border-light);
  background: var(--neutral-50);
}

/* Input Components */
.input {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  font-family: var(--font-family-sf);
  font-size: var(--text-base);
  background: var(--surface-primary);
  color: var(--text-primary);
  transition: all var(--transition-normal);
}

.input:focus {
  outline: none;
  border-color: var(--primary-blue);
  box-shadow: 0 0 0 3px rgba(0, 102, 255, 0.1);
}

.input::placeholder {
  color: var(--text-tertiary);
}

/* Badge Components */
.badge {
  display: inline-flex;
  align-items: center;
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  font-weight: var(--font-weight-medium);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

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

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

.badge-error {
  background: var(--error-light);
  color: var(--error);
}

.badge-info {
  background: var(--info-light);
  color: var(--info);
}

/* Status Indicators */
.status-indicator {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-full);
  font-size: var(--text-sm);
  font-weight: var(--font-weight-medium);
}

.status-good {
  background: var(--success-light);
  color: var(--success);
}

.status-warning {
  background: var(--warning-light);
  color: var(--warning);
}

.status-bad {
  background: var(--error-light);
  color: var(--error);
}

/* Loading States */
.loading {
  position: relative;
  overflow: hidden;
}

.loading::after {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
  animation: loading 1.5s infinite;
}

@keyframes loading {
  0% { left: -100%; }
  100% { left: 100%; }
}

/* Skeleton Loading */
.skeleton {
  background: linear-gradient(90deg, var(--neutral-200) 25%, var(--neutral-100) 50%, var(--neutral-200) 75%);
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s infinite;
}

@keyframes skeleton-loading {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* Animations */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes slideIn {
  from { transform: translateX(-100%); }
  to { transform: translateX(0); }
}

@keyframes scaleIn {
  from { transform: scale(0.95); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}

.animate-fade-in {
  animation: fadeIn var(--transition-normal) ease-out;
}

.animate-slide-in {
  animation: slideIn var(--transition-normal) ease-out;
}

.animate-scale-in {
  animation: scaleIn var(--transition-normal) ease-out;
}

/* Responsive Utilities */
@media (max-width: 768px) {
  .btn {
    padding: var(--space-4) var(--space-6);
    font-size: var(--text-lg);
  }
  
  .card {
    border-radius: var(--radius-xl);
  }
  
  .card-header,
  .card-body,
  .card-footer {
    padding: var(--space-4);
  }
}

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

/* Focus Styles */
.focus-visible {
  outline: 2px solid var(--primary-blue);
  outline-offset: 2px;
}

/* High Contrast Mode */
@media (prefers-contrast: high) {
  :root {
    --border-light: #000000;
    --border-medium: #000000;
    --text-secondary: #000000;
  }
}