diff --git a/index.d.ts b/index.d.ts
index ae8328f..17a8892 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,5 +1,5 @@
 export default function parse(color: string): {
-  space: 'rgb' | 'hsl' | 'hwb' | 'cmyk' | 'lab' | 'lch' | 'oklab' | 'oklch' | string;
+  space: 'rgb' | 'hsl' | 'hwb' | 'cmyk' | 'lab' | 'lch' | 'oklab' | 'oklch' | ({} & string);
   values: number[];
   alpha: number;
 }