For the backgrounds it’s not hard with multiple background images although the smoke animation might be a little difficult.
The parallax scrolling based on mouse position would be dependent on JS but that’s outside of my field of expertise.
The hover transition could probably be done with the translate property although I’m not entirely sure that it’s actually rolling like a louvre…it’s so quick it looks more like it’s just scrolling straight up .
I don’t know, if it would be a security risk it would be for users visiting dodgy sites. In Chrome it only seems to track mouse movement as long as you are hovering over the document, so you can’t track a user entering a password in an on-screen keyboard or something.