diff --git a/packages/@vuepress/core/lib/internal-plugins/overrideCSS.js b/packages/@vuepress/core/lib/internal-plugins/overrideCSS.js
index 597e74710e..c5ee319340 100644
--- a/packages/@vuepress/core/lib/internal-plugins/overrideCSS.js
+++ b/packages/@vuepress/core/lib/internal-plugins/overrideCSS.js
@@ -31,7 +31,7 @@ module.exports = (options, context) => ({
     await writeTemp('palette.styl', paletteContent)
 
     // style.styl API.
-    const stylePath = path.resolve(sourceDir, '.vuepress/style.styl').replace(/[\\]+/g, '/')
+    const stylePath = path.resolve(sourceDir, '.vuepress/style.styl').replace(/\\/g, '/')
     const hasUserStyle = fs.existsSync(stylePath)
     await writeTemp('style.styl', hasUserStyle ? `@import(${JSON.stringify(stylePath)})` : ``)