So basically I want to convert my collection of an html, css and javascript file into a single xml document. I searched a lot online but can't seem to find a solution. A bit of help guys?
The question implies a misunderstanding about XML.
XML provides a standard way to define markup languages. Many such vocabularies and grammars have been defined for many different types of data in many different industries. There has not been an XML schema defined to represent Dynamic HTML files, and there's no reason to expect one to be: The standard ways to combine HTML and JavaScript have been long established and standardized, and there would be no benefit to duplicate those mechanisms in XML.
If you want a single file of your HTML, CSS, and JavaScript files, consider putting them into a folder and zipping the folder into a single archive file.