diff --git a/src/webpack/utils.ts b/src/webpack/utils.ts
index 3295f93c..16dec5d9 100644
--- a/src/webpack/utils.ts
+++ b/src/webpack/utils.ts
@@ -1,7 +1,9 @@
+import { sep } from 'path'
+
 export function slash (path: string) {
   return path.replace(/\\/g, '/')
 }
 
 export function backSlash (path: string) {
-  return path.replace(/\//g, '\\')
+  return path.replace(/[\\/]/g, sep)
 }