:root {
  /* Colors - Primary (Green) */
  --color-primary-50: #e8f5e9;
  --color-primary-100: #c8e6c9;
  --color-primary-200: #a5d6a7;
  --color-primary-300: #81c784;
  --color-primary-400: #66bb6a;
  --color-primary-500: #329535;  /* Main brand green */
  --color-primary-600: #2e8731;
  --color-primary-700: #2c7a2e;
  --color-primary-800: #256825;
  --color-primary-900: #1b5e20;
  
  /* Colors - Secondary (Dark Blue/Gray) */
  --color-secondary-50: #eceff1;
  --color-secondary-100: #cfd8dc;
  --color-secondary-200: #b0bec5;
  --color-secondary-300: #90a4ae;
  --color-secondary-400: #78909c;
  --color-secondary-500: #1a2d35;  /* Main dark */
  --color-secondary-600: #172831;
  --color-secondary-700: #14232c;
  --color-secondary-800: #111e26;
  --color-secondary-900: #0d161a;
  
  /* Colors - Neutral Grays */
  --color-gray-50: #fafafa;
  --color-gray-100: #f5f5f5;
  --color-gray-200: #eeeeee;
  --color-gray-300: #e0e0e0;
  --color-gray-400: #bdbdbd;
  --color-gray-500: #9e9e9e;
  --color-gray-600: #757575;
  --color-gray-700: #616161;
  --color-gray-800: #424242;
  --color-gray-900: #212121;
  
  /* Colors - Semantic */
  --color-success: #4caf50;
  --color-warning: #ff9800;
  --color-error: #f44336;
  --color-info: #2196f3;
  
  /* Colors - Backgrounds */
  --color-bg-primary: #ffffff;
  --color-bg-secondary: #fafafa;
  --color-bg-tertiary: #f5f5f5;
  --color-bg-dark: var(--color-secondary-900);
  
  /* Typography - Font Families */
  --font-family-base: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-family-heading: 'Poppins', sans-serif;
  
  /* Typography - Font Sizes */
  --font-size-xs: 0.75rem;     /* 12px */
  --font-size-sm: 0.875rem;    /* 14px */
  --font-size-base: 1rem;      /* 16px */
  --font-size-lg: 1.125rem;    /* 18px */
  --font-size-xl: 1.25rem;     /* 20px */
  --font-size-2xl: 1.5rem;     /* 24px */
  --font-size-3xl: 1.875rem;   /* 30px */
  --font-size-4xl: 2.25rem;    /* 36px */
  --font-size-5xl: 3rem;       /* 48px */
  --font-size-6xl: 3.75rem;    /* 60px */
  --font-size-7xl: 4.5rem;     /* 72px */
  
  /* Typography - Responsive Sizes */
  --font-h1: clamp(2rem, 5vw, 3.5rem);
  --font-h2: clamp(1.75rem, 4vw, 2.5rem);
  --font-h3: clamp(1.5rem, 3vw, 2rem);
  --font-h4: clamp(1.25rem, 2.5vw, 1.5rem);
  --font-h5: clamp(1.125rem, 2vw, 1.25rem);
  --font-body: clamp(1rem, 2vw, 1.125rem);
  --font-small: clamp(0.875rem, 1.5vw, 1rem);
  
  /* Typography - Font Weights */
  --font-weight-light: 300;
  --font-weight-regular: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  
  /* Typography - Line Heights */
  --line-height-tight: 1.2;
  --line-height-snug: 1.375;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.625;
  --line-height-loose: 1.75;
  
  /* Typography - Letter Spacing */
  --letter-spacing-tight: -0.02em;
  --letter-spacing-normal: 0;
  --letter-spacing-wide: 0.02em;
  --letter-spacing-wider: 0.05em;
  
  /* Spacing System (8px base) */
  --space-0: 0;
  --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 */
  --space-32: 8rem;    /* 128px */
  
  /* Semantic Spacing */
  --space-xs: var(--space-2);
  --space-sm: var(--space-4);
  --space-md: var(--space-6);
  --space-lg: var(--space-8);
  --space-xl: var(--space-12);
  --space-2xl: var(--space-16);
  --space-3xl: var(--space-24);
  
  /* Layout */
  --container-max-width: 1280px;
  --container-padding: clamp(1rem, 5vw, 2rem);
  --section-padding-y: clamp(3rem, 8vw, 8rem);
  --content-max-width: 65ch;
  
  /* Borders */
  --border-width-thin: 1px;
  --border-width-normal: 2px;
  --border-width-thick: 4px;
  
  --border-radius-sm: 0.25rem;   /* 4px */
  --border-radius-md: 0.5rem;    /* 8px */
  --border-radius-lg: 0.75rem;   /* 12px */
  --border-radius-xl: 1rem;      /* 16px */
  --border-radius-2xl: 1.5rem;   /* 24px */
  --border-radius-full: 9999px;
  
  /* Shadows - Professional depth */
  --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 -1px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  --shadow-inner: inset 0 2px 4px 0 rgba(0, 0, 0, 0.05);
  
  /* Shadows - Colored */
  --shadow-primary: 0 10px 15px -3px rgba(50, 149, 53, 0.3);
  --shadow-secondary: 0 10px 15px -3px rgba(26, 45, 53, 0.3);
  
  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slower: 500ms cubic-bezier(0.4, 0, 0.2, 1);
  
  /* Easing Functions */
  --ease-in: cubic-bezier(0.4, 0, 1, 1);
  --ease-out: cubic-bezier(0, 0, 0.2, 1);
  --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);
  --ease-bounce: cubic-bezier(0.68, -0.55, 0.265, 1.55);
  
  /* Z-index Scale */
  --z-index-dropdown: 1000;
  --z-index-sticky: 1020;
  --z-index-fixed: 1030;
  --z-index-modal-backdrop: 1040;
  --z-index-modal: 1050;
  --z-index-popover: 1060;
  --z-index-tooltip: 1070;
  
  /* Breakpoints (for reference in JS) */
  --breakpoint-sm: 640px;
  --breakpoint-md: 768px;
  --breakpoint-lg: 1024px;
  --breakpoint-xl: 1280px;
  --breakpoint-2xl: 1536px;
}