demo · v136

Type-agnostic var()

Edit a registered <color> variable and a fallback expression. Pre-136, only colours were valid fallbacks; from 136, any string parses and only resolves against the property's own grammar.

actually used (var resolves)

resolved colour
--accent has a value, fallback is unused

fallback path (--accent unset)

fallback colour
…

the code

@property --accent {
  syntax: "<color>";
  inherits: false;
  initial-value: rebeccapurple;
}

.button {
  /* Pre-136: fallback "currentColor" rejected — not a <color> literal.
     136+: fallback parses as any value, validated against the property
     being assigned (color: here), so currentColor is fine. */
  color: var(--accent, currentColor);
}

see also