/* Theme knobs. Each colour family keeps its original hue offset / saturation ratio;
   themes shift hue (dh), scale saturation (s), and remap lightness (L' = lo + L * lk; dark themes use lk < 0). */
#couple-corner {
  --g-dh: 0deg; --g-s: 1;   /* main (green) */
  --a-dh: 0deg; --a-s: 1;   /* accent (peach / orange / brown) */
  --l-dh: 0deg; --l-s: 1;   /* lilac */
  --p-dh: 0deg; --p-s: 1;   /* paper / neutrals */
  --lo: 0%; --lk: 1;
  --cc-white: hsl(calc(53deg + var(--p-dh)) calc(100% * var(--p-s)) calc(var(--lo) + 98% * var(--lk)));
  --cc-black: hsl(calc(97deg + var(--g-dh)) calc(15% * var(--g-s)) calc(var(--lo) + 12% * var(--lk)));
}
#couple-corner[data-dark=true] { color-scheme: dark; }