Hi @anupent,
You would simply add something like this to your HTML…
<link rel="stylesheet" type="text/css" href="stylesheet.css">
…where stylesheet.css is the name of the CSS file (on your client machine) that you upload as a dependent file.
Note that there are a couple of relevant commits you might find helpful: one to improve MIME type detection of CSS files, and one to prevent multiple files with the same name colliding when resolving the names of dependent files. These are both included in the ojs-stable-3_0_0 branch, if you’re working with that.
Regards,
Alec Smecher
Public Knowledge Project Team