:root{
  /* Calm elevation. Cards are hairline-bordered first, shadowed second. */
  --shadow-xs:0 1px 2px rgba(8,24,47,0.04);
  --shadow-sm:0 1px 3px rgba(8,24,47,0.06);
  --shadow-md:0 4px 14px -4px rgba(8,24,47,0.10);
  --shadow-lg:0 16px 40px -12px rgba(8,24,47,0.14);
  --shadow-xl:0 28px 64px -20px rgba(8,24,47,0.18);
  --shadow-green:0 10px 24px -10px rgba(43,192,10,0.45);
  --ring-focus:0 0 0 3px rgba(43,192,10,0.35);
  --hairline:inset 0 0 0 1px rgba(8,24,47,0.08); /* @kind shadow */
}