:root {
  /* Color Palette - Inspired by Stripe, Linear, Vercel */
  --color-bg: #f8fafc; /* Light gray */
  --color-bg-alt: #f1f5f9; /* Slate-50 */
  --color-text: #1e293b; /* Dark blue */
  --color-muted: #64748b; /* Slate gray */
  --color-card-bg: #ffffff;
  --color-card-border: #e2e8f0;
  --color-primary: #3b82f6; /* Blue */
  --color-primary-hover: #2563eb;
  --color-secondary: #10b981; /* Emerald */
  --color-accent: #34d399; /* Mint */
  --color-danger: #ef4444; /* Red */
  --color-warning: #f59e0b; /* Amber */
  --color-success: #10b981; /* Green */
  --color-error: #ef4444; /* Red (same as danger) */

  /* Gradient */
  --gradient-primary: linear-gradient(135deg, #3b82f6, #10b981);
  --gradient-secondary: linear-gradient(135deg, #8b5cf6, #ec4899);

  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
  --font-serif: 'Merriweather', Georgia, serif;
  --font-mono: 'Fira Code', 'Courier New', monospace;

  --font-weight-light: 300;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  --font-weight-black: 800;

  --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 */

  /* Spacing (8px grid) */
  --spacing-0: 0;
  --spacing-05: 0.125rem; /* 2px */
  --spacing-1: 0.25rem; /* 4px */
  --spacing-15: 0.375rem; /* 6px */
  --spacing-2: 0.5rem; /* 8px */
  --spacing-25: 0.625rem; /* 10px */
  --spacing-3: 0.75rem; /* 12px */
  --spacing-35: 0.875rem; /* 14px */
  --spacing-4: 1rem; /* 16px */
  --spacing-5: 1.25rem; /* 20px */
  --spacing-6: 1.5rem; /* 24px */
  --spacing-7: 1.75rem; /* 28px */
  --spacing-8: 2rem; /* 32px */
  --spacing-9: 2.25rem; /* 36px */
  --spacing-10: 2.5rem; /* 40px */
  --spacing-12: 3rem; /* 48px */
  --spacing-14: 3.5rem; /* 56px */
  --spacing-16: 4rem; /* 64px */
  --spacing-20: 5rem; /* 80px */
  --spacing-24: 6rem; /* 96px */

  /* Border Radius */
  --radius-none: 0;
  --radius-sm: 0.25rem; /* 4px */
  --radius-md: 0.5rem; /* 8px */
  --radius-lg: 0.75rem; /* 12px */
  --radius-xl: 1rem; /* 16px */
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --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 -2px 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);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow: 350ms ease;

  /* Animations */
  --animation-in: fade-in 0.5s ease forwards;
  --animation-up: slide-up 0.5s ease forwards;

  /* Container */
  --container-width: 1200px;
  --container-padding: 1.5rem; /* 24px */

  /* Z-index */
  --z-index-drawer: 1000;
  --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;
}

/* Dark Theme (when .dark-theme class is applied to html) */
.dark-theme {
  --color-bg: #0f172a; /* Navy */
  --color-bg-alt: #020617; /* Even darker for alternating sections */
  --color-text: #f9fafb; /* Off-white */
  --color-muted: #94a3b8; /* Light slate */
  --color-card-bg: #1e293b; /* Dark slate */
  --color-card-border: #334155;
  --color-primary: #60a5fa; /* Light blue */
  --color-primary-hover: #3b82f6;
  --color-accent: #34d399; /* Mint */
  --color-danger: #ef4444; /* Red */
  --color-warning: #f59e0b; /* Amber */
  --color-success: #10b981; /* Green */
  /* In dark theme, we keep the same semantic colors */
  --color-error: #ef4444; /* Red (same as danger) */
}