Primary and secondary width

How can I make the secondary area be at the right of the post, and not at the bottom, if you take a look on:

http://qpuntto.com/mi-vida-por-una-de-chorizo/

I´ve tried the following code:

#secondary {
  width: 35% !important;
}
#primary {
  width: 65% !important;
}

It works but it affects all the pages at a width of 65%, so I decided to remove the #primary´s code, is there a way of doing it just when having a secondary area (side widget)???

URL: http://qpuntto.com/mi-vida-por-una-de-chorizo/