Path resolve error

[RedTeapot]

It would report "File not found with singular glob: F:\proj\build\tmp\html\js\plugin\swiper\swiper.min.css" while processing "index.html" in the flollowing tree:

html
　|- main
　　|- customer
　　　|- E238
　　　　|- index.html
js
　|- plugin
　　|- swiper
　　　|- swiper.min.css

Build block:
<!-- build:css ../../../../css/main/customer/E238/index.html.allinone.css -->
<link rel = "stylesheet" href="../../../../js/plugin/swiper/swiper.min.css"/>
<!-- endbuild -->