:root {
  /* Backgrounds — depth layers from darkest to lightest */
  --bg-void: #080a0f;
  --bg-deep: #0c0f14;
  --bg-surface: #111620;
  --bg-elevated: #161c28;
  --bg-glass: rgba(17, 22, 32, 0.8);

  /* Brand — Electric Cyan */
  --cyan: #00d4ff;
  --cyan-dim: #00a8cc;
  --cyan-glow: rgba(0, 212, 255, 0.15);
  --cyan-text: #7dd8f0;

  /* Semantic */
  --green: #00ff88;
  --green-dim: #00cc6a;
  --amber: #ffb800;
  --amber-dim: #cc9200;
  --red: #ff4757;
  --red-dim: #cc3945;

  /* Text — warm grays for readability */
  --text-primary: #e8eaed;
  --text-secondary: #9ca3af;
  --text-muted: #6b7280;
  --text-disabled: #4b5563;

  /* Borders */
  --border-default: #1e2530;
  --border-subtle: #161c28;
  --border-active: #00d4ff;
  --border-hover: #2a3341;

  /* Gradients */
  --gradient-hero: linear-gradient(135deg, #0c0f14 0%, #0a1628 50%, #0c0f14 100%);
  --gradient-card: linear-gradient(180deg, #161c28 0%, #111620 100%);
  --gradient-cta: linear-gradient(135deg, #00d4ff 0%, #00a8cc 100%);
  --gradient-surface: linear-gradient(180deg, rgba(0,212,255,0.03) 0%, transparent 100%);

  /* Typography */
  --font-heading: 'JetBrains Mono', 'Fira Code', monospace;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-code: 'JetBrains Mono', 'Fira Code', monospace;

  /* Fluid scale with clamp() */
  --text-display: clamp(2.5rem, 5vw, 3.5rem);
  --text-h1: clamp(2rem, 4vw, 2.75rem);
  --text-h2: clamp(1.5rem, 3vw, 2rem);
  --text-h3: clamp(1.125rem, 2vw, 1.375rem);
  --text-body: 1rem;
  --text-small: 0.875rem;
  --text-tiny: 0.75rem;
  --text-code: 0.8125rem;

  --leading-tight: 1.2;
  --leading-normal: 1.6;
  --leading-relaxed: 1.8;

  --tracking-tight: -0.02em;
  --tracking-normal: 0;
  --tracking-wide: 0.05em;
  --tracking-mono: 0.02em;

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;
  --section-padding: clamp(5rem, 10vw, 8rem);

  /* Components + Transitions */
  --card-radius: 2px;
  --card-border: 1px solid var(--border-default);
  --card-shadow: 0 1px 3px rgba(0,0,0,0.3);
  --card-shadow-hover: 0 4px 12px rgba(0,0,0,0.4), 0 0 0 1px var(--border-hover);
  --card-padding: var(--space-8);

  --btn-radius: 2px;
  --btn-height: 2.5rem;
  --btn-height-lg: 3rem;

  --input-radius: 2px;
  --input-height: 2.75rem;
  --input-border: 1px solid var(--border-default);
  --input-focus: 0 0 0 2px var(--cyan-glow), 0 0 0 1px var(--cyan);

  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-spring: 500ms cubic-bezier(0.34, 1.56, 0.64, 1);

  --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-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
}