:root {
  /* Brand */
  --blue-50:  #eff6ff;
  --blue-100: #dbeafe;
  --blue-500: #3b82f6;
  --blue-600: #2563eb;
  --blue-700: #1d4ed8;
  --blue-800: #1e3a8a;
  --blue-900: #0f2356;

  /* Neutrals */
  --gray-50:  #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-800: #1f2937;
  --gray-900: #111827;

  /* Semantic */
  --color-error:       #dc2626;
  --color-error-bg:    #fef2f2;
  --color-error-border:#fecaca;
  --color-success:     #16a34a;
  --color-warning:     #d97706;

  /* Layout */
  --radius-sm:   6px;
  --radius-md:   10px;
  --radius-lg:   16px;
  --radius-xl:   24px;

  --shadow-sm: 0 1px 2px rgba(0,0,0,.05);
  --shadow-md: 0 4px 16px rgba(0,0,0,.08);
  --shadow-lg: 0 12px 40px rgba(0,0,0,.12);

  --transition: 0.18s ease;
}