¿Load another html+css file when site is being surfed on Mobile?

Here´s my problem: I´ve started building my portfolio page a long time ago. By that time I didn´t know about responsive design so i thought “later in the future i´ll add the responsive design so it can be viewed well on mobile”.

So know my html is built in a way its very difficult for me to add media queries, so i was wondering if there´s possible to add a media query that if it passes it will load another html+css file. Basically building a whole new website for mobile, instead of using a single html.

Hey there,

If this problem is still relevant, are you specifically wanting to use media queries to accomplish this? Or, specifically just CSS? Or, are you open to another solution?