diff --git a/.vitepress/config.ts b/.vitepress/config.ts
index 4e37b75..b582f18 100644
--- a/.vitepress/config.ts
+++ b/.vitepress/config.ts
@@ -13,7 +13,7 @@ import { fileURLToPath } from "url";
  */
 function walkSync(dir: string, filelist: string[] = []) {
 	// add trailing slash if not present
-	if (dir.at(-1) != sep) dir += sep;
+	if (!dir.endsWith(sep)) dir += sep;
 	for (const file of readdirSync(dir)) {
 		if (statSync(dir + file).isDirectory())
 			// read directories inside directories recursively