:root {
  /* Colors - Primary Palette */
  --color-primary: #2563eb;
  --color-primary-rgb: 37, 99, 235;
  --color-primary-dark: #1e40af;
  --color-primary-light: #3b82f6;
  
  /* Colors - Secondary Palette */
  --color-secondary: #f97316;
  --color-secondary-rgb: 249, 115, 22;
  --color-secondary-dark: #ea580c;
  --color-secondary-light: #fb923c;
  
  /* Colors - Accent Palette */
  --color-accent: #10b981;
  --color-accent-rgb: 16, 185, 129;
  --color-accent-dark: #059669;
  --color-accent-light: #34d399;
  
  /* Colors - Neutral Palette */
  --color-bg-primary: #ffffff;
  --color-bg-secondary: #f8fafc;
  --color-bg-tertiary: #f1f5f9;
  --color-bg-dark: #0f172a;
  --color-bg-dark-secondary: #1e293b;
  
  /* Colors - Text */
  --color-text-primary: #1e293b;
  --color-text-secondary: #64748b;
  --color-text-muted: #94a3b8;
  --color-text-light: #ffffff;
  --color-text-inverse: #ffffff;
  
  /* Colors - Border */
  --color-border: #e2e8f0;
  --color-border-dark: #cbd5e1;
  --color-border-light: #f1f5f9;
  
  /* Colors - Status */
  --color-success: #10b981;
  --color-success-rgb: 16, 185, 129;
  --color-error: #ef4444;
  --color-error-rgb: 239, 68, 68;
  --color-warning: #f59e0b;
  --color-warning-rgb: 245, 158, 11;
  --color-info: #3b82f6;
  --color-info-rgb: 59, 130, 246;
  
  /* Typography */
  --font-family-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-family-heading: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;
  
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  
  --line-height-tight: 1.25;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.75;
  
  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  
  /* Border Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  --shadow-colored: 0 10px 15px -3px rgba(37, 99, 235, 0.3);
  
  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-base: 300ms ease-in-out;
  --transition-slow: 500ms ease-in-out;
  
  /* Z-Index */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
  
  /* Layout */
  --container-max-width: 1280px;
  --container-padding: var(--spacing-md);
  
  /* Gradients */
  --gradient-primary: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
  --gradient-secondary: linear-gradient(135deg, var(--color-secondary) 0%, var(--color-accent) 100%);
  --gradient-accent: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
}

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

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

body {
  font-family: var(--font-family-primary);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  color: var(--color-text-primary);
  background-color: var(--color-bg-primary);
  overflow-x: hidden;
}

body.modal-open {
  overflow: hidden;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-family-heading);
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
  color: var(--color-text-primary);
  margin-bottom: var(--spacing-md);
  scroll-margin-top: 80px;
}

h1 { font-size: var(--font-size-5xl); }
h2 { font-size: var(--font-size-4xl); }
h3 { font-size: var(--font-size-3xl); }
h4 { font-size: var(--font-size-2xl); }
h5 { font-size: var(--font-size-xl); }
h6 { font-size: var(--font-size-lg); }

p {
  margin-bottom: var(--spacing-md);
  color: var(--color-text-secondary);
}

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

a:hover {
  color: var(--color-primary-dark);
}

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

ul, ol {
  margin-bottom: var(--spacing-md);
  padding-left: var(--spacing-xl);
}

li {
  margin-bottom: var(--spacing-sm);
}

/* Container */
.container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

/* Section */
.section {
  padding: var(--spacing-3xl) 0;
}

.section-title {
  text-align: center;
  margin-bottom: var(--spacing-2xl);
}

.section-subtitle {
  text-align: center;
  color: var(--color-text-secondary);
  font-size: var(--font-size-lg);
  max-width: 700px;
  margin: 0 auto var(--spacing-2xl);
}

/* Buttons */
.btn {
  display: inline-block;
  padding: var(--spacing-md) var(--spacing-xl);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-semibold);
  text-align: center;
  border: none;
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-base);
  text-decoration: none;
}

.btn-primary {
  background: var(--gradient-primary);
  color: var(--color-text-light);
  box-shadow: var(--shadow-md);
}

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

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

.btn-secondary:hover {
  background-color: var(--color-bg-tertiary);
  border-color: var(--color-border-dark);
  color: var(--color-text-primary);
}

/* Cards */
.card {
  background: var(--color-bg-primary);
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
  border: 1px solid var(--color-border-light);
}

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

.card-img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-radius: var(--radius-lg);
  margin-bottom: var(--spacing-md);
}

.card-title {
  font-size: var(--font-size-xl);
  margin-bottom: var(--spacing-sm);
  color: var(--color-text-primary);
}

.card-text {
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-md);
}

/* Grid */
.grid {
  display: grid;
  gap: var(--spacing-xl);
}

.grid-2 { 
  grid-template-columns: repeat(2, 1fr); 
}
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* Responsive grid-2 with 4 items */
.grid-2:has(> :nth-child(4)) {
  grid-template-columns: repeat(2, 1fr);
}

/* Responsive */
@media (max-width: 1023px) {
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  
  /* Keep grid-2 with 4 items as 2 columns on tablet */
  .grid-2:has(> :nth-child(4)) {
    grid-template-columns: repeat(2, 1fr) !important;
  }
  
  /* Responsive inline grid styles */
  [style*="grid-template-columns: repeat(2, 1fr)"]:has(> :nth-child(4)) {
    grid-template-columns: repeat(2, 1fr) !important;
  }
}

@media (max-width: 767px) {
  html { font-size: 14px; }
  
  /* On mobile, all grids become 1 column, including grid-2 with 4 items */
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr !important;
  }
  
  /* Override the tablet rule for mobile */
  .grid-2:has(> :nth-child(4)) {
    grid-template-columns: 1fr !important;
  }
  
  /* Make inline grid styles responsive on mobile */
  [style*="grid-template-columns: repeat(2, 1fr)"] {
    grid-template-columns: 1fr !important;
  }
  
  /* Override the tablet rule for inline grids with 4 items on mobile */
  [style*="grid-template-columns: repeat(2, 1fr)"]:has(> :nth-child(4)) {
    grid-template-columns: 1fr !important;
  }
  
  /* Timeline responsive */
  [style*="padding-left: calc(var(--spacing-xl) + 72px)"] {
    padding-left: var(--spacing-xl) !important;
  }
  
  [style*="padding-left: calc(var(--spacing-xl) + 35px)"] {
    padding-left: var(--spacing-xl) !important;
  }
  
  [style*="max-width: 800px"][style*="padding-left"] {
    margin-bottom: var(--spacing-xl) !important;
  }
  
  /* Timeline items responsive margin */
  [style*="max-width: 800px"][style*="padding-left"] > [style*="position: relative"] {
    margin-bottom: var(--spacing-xl) !important;
  }
  
  [style*="left: -70px"] {
    left: 0 !important;
    transform: none !important;
    position: relative !important;
    margin-bottom: var(--spacing-xl) !important;
  }
  
  [style*="left: 35px"] {
    display: none !important;
  }
  
  h1 { font-size: var(--font-size-4xl); }
  h2 { font-size: var(--font-size-3xl); }
  h3 { font-size: var(--font-size-2xl); }
  
  .section {
    padding: var(--spacing-2xl) 0;
  }
}