:root {
  --primary: #1a56db;
  --secondary: #f8fafc;
  --text: #334155;
  --text-muted: #64748b;
  --cta: #2563eb;
  --accent: #3b82f6;
  --bg: #f5f7fa;
  --surface: #fff;
  --border: #e2e8f0;
  --radius: 14px;
  --shadow: 0 4px 20px rgba(0, 0, 0, .08);
  --nav-h: 56px;
  --footer-h: 72px;
  --safe-bottom: env(safe-area-inset-bottom, 0);
}

[data-theme="tech"] { color-scheme: dark; }
[data-theme="tech"] body { --bg: #0f172a; --surface: #1e293b; --text-muted: #94a3b8; }