Viewi has a helper component that allows you to include your css file(s). It has the following syntax:
<CssBundle link="/css/main.css" />
But if you need to include more than one file you can use:
<CssBundle links="{['/css/main.css', '/css/admin.css', '/css/icons.css']}" />
Additionally Css Bundle supports a couple more features:
<CssBundle links="{['/css/main.css', '/css/admin.css', '/css/icons.css']}" minify="true" shakeTree="true" combine="true" inline="true" />
Where: