That is it!
Brilliant, many thanks for your help.
The site is a work in progress, I wanted to make sure it worked before I transferred it to a different host:
http://rcs.kelcey.co.uk/wp/
Fixed this, it must of been a dodgy install of WP/Customizr, I deleted the entire install and started again.
Its all working fine now.
I’m new to using CSS, the background is created like this:
body {
background: url(my image url) ;
}
I’m not sure if I add the @media into the body section or as a seperate section?