How does webpack4 package multiple independent css?

how does webpack4 package multiple independent css
for example, you need to generate 2 css

all.css //css
a.css

both css are generated by packaging and merging of several third-party css.
if you package a css, you can reference a third-party css, one by one in js and then package it to generate, but the above two need to be packaged separately

Sep.23,2021
Menu