:root{
  /* Two levels only. Shadows are navy-tinted, never grey-black. */
  --shadow-flat:none;
  --shadow-raised:0 1px 2px rgba(2,54,93,.10);
  --shadow-lifted:0 6px 18px rgba(2,54,93,.14);
  --shadow-inset-field:inset 0 1px 0 rgba(2,54,93,.06);
}