Removing padding on "Boxed" mobile layout

Hi,

I have a boxed layout on desktop version, on mobile though the padding is a bit too much and the website is very thin. I want to remove the padding on mobile (but not on desktop) so that it is full width on mobile only. I found this code on the TF in the comments


@media only screen and (max-width: 479px) {
    body{padding:0!important; }
    #Wrapper { width: 479px!important; }
}


and applied this but it doesn't do anything :(  (I do not have any cache plugins installed and refreshed several times)

Is there a way i can achieve this full width on mobile but remain boxed on desktop?

http://tinypic.com/r/34hi3up/9

Thx