:root{
  /* soft, cool-tinted elevation — teal-black at low alpha */
  --shadow-xs:0 1px 2px rgba(16,24,24,0.06);
  --shadow-sm:0 2px 6px rgba(16,24,24,0.07);
  --shadow-md:0 8px 20px rgba(16,24,24,0.08);
  --shadow-lg:0 16px 40px rgba(16,24,24,0.10);
  --shadow-brand:0 10px 24px rgba(15,163,163,0.28);
  --shadow-focus:0 0 0 3px rgba(15,163,163,0.28);
  --shadow-inner:inset 0 1px 2px rgba(16,24,24,0.06);
}